Search

Purpose: The National Association for Proton Therapy conducted 8 surveys of all operational United States proton centers (2012-2021) and analyzed the patients treated, diagnoses, and treatment complexity to evaluate trends and diversification of patients receiving proton therapy., Methods and Materials: Detailed surveys were sent in 2015, which requested data from 2012 to 2014, and then annually thereafter to active proton centers in the United States. The numbers of patient treated at each center for the preceding calendar year(s) were collated for tumors in the following categories: central nervous system, intraocular, pituitary, skull base/skeleton, head/neck, lung, retroperitoneal/soft tissue sarcoma, pediatric (solid tumors in children of age ≤18), gastrointestinal tract, urinary tract, female pelvic, prostate, breast, and "other." Complexity levels were assessed using Current Procedural Terminology codes 77520-77525., Results: Survey response rates were excellent (100% in 2015 to 94.9% in 2021); additional publicly available information provided near-complete information on all centers. Trend comparisons between 2012 and 2021 showed that the total annual number of patients treated with protons gradually increased from 5377 to 15,829. The largest numeric increases were for head/neck (316 to 2303; 7.3-fold), breast (93 to 1452; 15.6-fold), and gastrointestinal tumors (170 to 1259; 7.4-fold). Patient numbers also increased significantly for central nervous system (598 to 1743; 2.9-fold), pediatric (685 to 1870; 2.7-fold), and skull base tumors (179 to 514; 2.9-fold). For prostate cancer, the percentage of proton-treated patients decreased from 43.4% to 25.0% of the total. Simple compensated treatments decreased from 43% in 2012 to 7% in 2021, whereas intermediate complexity treatments increased from 45% to 73%., Conclusions: The number of patients treated with protons is gradually increasing, with a substantial proportionate decline in patients with prostate cancer receiving proton therapy. The number of patients treated for "commonly accepted" indications for protons (eg, pediatric, central nervous system, and skull base tumors) is gradually increasing. Greater proportional increases were observed for breast, lung, head/neck, and gastrointestinal tumors. Treatment complexity is gradually increasing over time., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Proton beam therapy (PBT) has great advantages as tumor radiotherapy and is progressively becoming a more prevalent choice for individuals undergoing radiation therapy. The objective of this review is to pinpoint collaborative efforts among countries and institutions, while also exploring the hot topics and future outlook in the field of PBT. Data from publications were downloaded from the Web of Science Core Collection. CiteSpace and Excel 2016 were used to conduct the bibliometric and knowledge map analysis. A total of 6516 publications were identified, with the total number of articles steadily increasing and the United States being the most productive country. Harvard University took the lead in contributing the highest number of publications. Paganetti Harald published the most articles and had the most cocitations. PHYS MED BIOL published the greatest number of PBT-related articles, while INT J RADIAT ONCOL received the most citations. Paganetti Harald, 2012, PHYS MED BIOL can be classified as classic literature due to its high citation rate. We believe that research on technology development, dose calculation and relative biological effectiveness were the knowledge bases in this field. Future research hotspots may include clinical trials, flash radiotherapy, and immunotherapy., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Importance: Proton beam therapy is an emerging radiotherapy treatment for patients with cancer that may produce similar outcomes as traditional photon-based therapy for many cancers while delivering lower amounts of toxic radiation to surrounding tissue. Geographic proximity to a proton facility is a critical component of ensuring equitable access both for indicated diagnoses and ongoing clinical trials., Objective: To characterize the distribution of proton facilities in the US, quantify drive-time access for the population, and investigate the likelihood of long commutes for certain population subgroups., Design, Setting, and Participants: This population-based cross-sectional study analyzed travel times to proton facilities in the US. Census tract variables in the contiguous US were measured between January 1, 2017, and December 31, 2021. Statistical analysis was performed from September to November 2023., Exposures: Drive time in minutes to nearest proton facility. Population totals and prevalence of specific factors measured from the American Community Survey: age; race and ethnicity; insurance, disability, and income status; vehicle availability; broadband access; and urbanicity., Main Outcomes and Measures: Poor access to proton facilities was defined as having a drive-time commute of at least 4 hours to the nearest location. Median drive time and percentage of population with poor access were calculated for the entire population and by population subgroups. Univariable and multivariable odds of poor access were also calculated for certain population subgroups., Results: Geographic access was considered for 327 536 032 residents of the contiguous US (60 594 624 [18.5%] Hispanic, 17 974 186 [5.5%] non-Hispanic Asian, 40 146 994 [12.3%] non-Hispanic Black, and 195 265 639 [59.6%] non-Hispanic White; 282 031 819 [86.1%] resided in urban counties). The median (IQR) drive time to the nearest proton facility was 96.1 (39.6-195.3) minutes; 119.8 million US residents (36.6%) lived within a 1-hour drive of the nearest proton facility, and 53.6 million (16.4%) required a commute of at least 4 hours. Persons identifying as non-Hispanic White had the longest median (IQR) commute time at 109.8 (48.0-197.6) minutes. Multivariable analysis identified rurality (odds ratio [OR], 2.45 [95% CI, 2.27-2.64]), age 65 years or older (OR, 1.09 [95% CI, 1.06-1.11]), and living below the federal poverty line (OR, 1.22 [1.20-1.25]) as factors associated with commute times of at least 4 hours., Conclusions and Relevance: This cross-sectional study of drive-time access to proton beam therapy found that disparities in access existed among certain populations in the US. These results suggest that such disparities present a barrier to an emerging technology in cancer treatment and inhibit equitable access to ongoing clinical trials.

Purpose: Protontherapy for mediastinal Hodgkin lymphoma reduces cardiac, lung and breast exposure, which may limit radiation-induced adverse events. While this technique is already widely implemented in the United-States, clinical experience is still limited in France. This study analyses the practice of mediastinal Hodgkin lymphoma protontherapy at the Institut Curie to implement this technique at a larger scale., Materials and Methods: Data from all mediastinal Hodgkin lymphoma patients from the hematology department of the Institut Curie who were subsequently evaluated at the Protontherapy Center of Orsay (CPO) of Institut Curie for adjuvant protontherapy were retrieved. We analyzed why these patients were ultimately treated with protontherapy or not., Results: Between January 2018 and January 2021, twenty mediastinal Hodgkin lymphoma patients from the hematology department of the Institut Curie have been screened for protontherapy at the CPO. Four of them (20%) were ultimately treated with proton beams. Treatment was well tolerated without grade 3-4 adverse events. With a median follow-up of two years, none of these patients relapsed. The others sixteen patients were not treated with protontherapy due to multiple reasons including: lack of treatment room disponibility, accessibility difficulties, psychiatric disorder, and anatomic or dosimetric considerations., Conclusion: Despite notable dosimetric superiority over photon radiotherapy and excellent clinical tolerance, lack of availability of protontherapy facilities limit implementation of mediastinal Hodgkin lymphoma protontherapy. Additionally, strict selection criteria must be defined., (Copyright © 2021 Société française de radiothérapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.)

Purpose: Proton beam therapy (PBT) is a state-of-the-art technology employed in radiotherapy (RT) for cancer patients. This study characterized how PBT has been used in clinical practice in Korea., Materials and Methods: Patients who received any type of RT between 2007 and 2019 were identified from the radiation oncology registry of the two PBT facilities operating in Korea (National Cancer Center and Samsung Medical Center). The chi-square test was used to identify patient- and treatment-related characteristics associated with the receipt of PBT., Results: A total of 54,035 patients had been treated with some form of RT in the two institutions, of whom 5,398 received PBT (10.0%). The number of patients who receive PBT has gradually increased since PBT first started, from 162 patients in 2007 to 1,304 patients in 2019. Among all types of cancer, PBT use in liver cancer has been steadily increasing from 20% in 2008-2009 to 32% in 2018-2019. In contrast, that in prostate cancer has been continuously decreasing from 20% in 2008-2009 to < 10% in 2018-2019. Male sex, very young or old age, stage I-II disease, residency in non-capital areas, a definitive setting, a curative treatment aim, enrollment in a clinical trial, re-irradiation and insurance coverage were significantly associated with the receipt of PBT (all p < 0.05)., Conclusion: Since PBT started in Korea, the number of patients receiving PBT has increased to more than 1,000 per year and treatment indications have expanded. Liver cancer is the most common primary tumor among all PBT cases in Korea.

Purpose: Young patients, including pediatric, adolescent, and young adult (YA) patients, are most likely to benefit from the reduced integral dose of proton beam radiation therapy (PBT) resulting in fewer late toxicities and secondary malignancies. This study sought to examine insurance approval and appeal outcomes for PBT among YA patients compared with pediatric patients at a large-volume proton therapy center., Methods and Materials: We performed a cross-sectional cohort study of 284 consecutive patients aged 0 to 39 years for whom PBT was recommended in 2018 through 2019. Pediatric patients were defined as aged 0 to 18 years and YA patients 19 to 39 years. Rates of approval, denials, and decision timelines were calculated. Tumor type and location were also evaluated as factors that may influence insurance decisions., Results: A total of 207 patients (73%) were approved for PBT at initial request. YA patients (n = 68/143, 48%) were significantly less likely to receive initial approval compared with pediatric patients (n = 139/141; 99%) (P < .001). Even after 47% (n = 35 of 75) of the PBT denials for YA patients were overturned, YAs had a significantly lower final PBT approval (72% vs pediatric 99%; P < .001). The median wait time was also significantly longer for YA patients (median, 8 days; interquartile range [IQR] 3-17 vs median, 2 days; IQR, 0-6; P < .001). In those patients requiring an appeal, the median wait time was 16 days (IQR, 9-25)., Conclusion: Given the decades of survivorship of YA patients, PBT is an important tool to reduce late toxicities and secondary malignancies. Compared with pediatric patients, YA patients are significantly less likely to receive insurance approval for PBT. Insurance denials and subsequent appeal requests result in significant delays for YA patients. Insurers need to re-examine their policies to include expedited decisions and appeals and removal of arbitrary age cutoffs so that YA patients can gain easier access to PBT. Furthermore, consensus guidelines encouraging greater PBT access for YA may be warranted from both medical societies and/or AYA experts., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Purpose: Breast protontherapy efficiently limits cardiac, lung and contralateral breast exposure, which may clinically translate into better late tolerance profile compared with classic photon techniques. While breast protontherapy is already implemented in the United States and in some European countries, clinical experience of breast cancer protontherapy is currently limited in France. The aim of this study is to evaluate the clinical practice of breast cancer protontherapy at the Institut Curie in order to implement this technique at a larger scale., Materials and Methods: Data from all breast cancer patients that have been addressed to the protontherapy centre of Orsay (CPO, Institut Curie) for adjuvant breast protontherapy were retrieved. We analysed why these patients were ultimately treated with protontherapy or not., Results: Between November 2019 and November 2020, eleven breast cancer patients have been evaluated for adjuvant protontherapy at the CPO. Two of them were ultimately treated with proton beams; adjuvant breast protontherapy therapy was well tolerated. The nine other patients were not treated with protontherapy due to lack of availability of protontherapy treatment rooms in acceptable time limits, at the time of patient evaluation., Conclusion: Despite dosimetric advantages and excellent clinical tolerance, lack of availability of protontherapy machines currently limits wider implementation of breast protontherapy., (Copyright © 2021 Société française de radiothérapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.)

Purpose: Several definitive treatment options are available for prostate cancer, but geographic access to those options is not uniform. We created maps illustrating provider practice patterns relation to patients and assessed the influence of distance to treatment receipt., Methods and Materials: The patient cohort was created by searching the National Medicare Database for patients diagnosed and treated for prostate cancer from 2011 to 2014. The provider cohort was created by querying the American Medical Association Physician Masterfile to identify physicians who had treated patients with prostatectomy, intensity modulated radiation therapy (IMRT), brachytherapy, stereotactic body radiation therapy (SBRT), or proton therapy. Maps detailing the location of providers were created for each modality. Multivariate multinomial logistic regressions were used to assess the association between patient-provider distance and probability of treatment., Results: Cohorts consisted of 89,902 patients treated by 5518 physicians. Substantial numbers of providers practicing established modalities (IMRT, prostatectomy, and brachytherapy) were noted in major urban centers, whereas provider numbers were reduced in rural areas, most notably for brachytherapy. Ninety percent of prostate cancer patients lived within 35.1, 28.9, and 55.6 miles of a practitioner of prostatectomy, IMRT, and brachytherapy, respectively. Practitioners of emerging modalities (SBRT and proton therapy) were predominantly concentrated in urban locations, with 90% of patients living within 128 miles (SBRT) and 374.5 miles (proton). Greater distance was associated with decreased probability of treatment (IMRT -3.8% per 10 miles; prostatectomy -2.1%; brachytherapy -2%; proton therapy -1.6%; and SBRT -1.1%)., Conclusions: Geographic disparities were noted for analyzed treatment modalities, and these disparities influenced delivery., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The aim of this study is to compare the effectiveness of carbon ion radiation therapy (CIRT), proton radiation therapy (PRT), and photon-based intensity-modulated radiation therapy (IMRT) in the treatment of sinonasal malignancies. We identified studies through systematic review and divided them into three cohorts (CIRT group/PRT group/IMRT group). Primary outcomes of interest were overall survival (OS) and local control (LC). We pooled the outcomes with meta-analysis and compared the survival difference among groups using Chi 2 (χ 2 ) test. A representative sample of 2282 patients with sinonasal malignancies (911 in the CIRT group, 599 in the PRT group, and 772 in the IMRT group) from 44 observation studies (7 CIRT, 16 PRT, and 21 IMRT) was included. The pooled 3-year OS, LC, distant metastasis-free survival, and progression-free survival rates were 67.0%, 72.8%, 69.4%, and 52.8%, respectively. Through cross-group analysis, the OS was significantly higher after CIRT (75.1%, 95% CI: 67.1%-83.2%) than PRT (66.2%, 95% CI: 57.7%-74.6%; χ 2  = 13.374, P < .0001) or IMRT (63.8%, 95% CI: 55.3%-72.3%; χ 2  = 23.814, P < .0001). LC was significantly higher after CIRT (80.2%, 95% CI: 73.9%-86.5%) than PRT (72.9%, 95% CI: 63.7%-82.0%; χ 2  = 8.955, P = .003) or IMRT (67.8%, 95% CI: 59.4%-76.2%; χ 2  = 30.955, P < .0001). However, no significant difference between PRT and IMRT for OS and LC was observed. CIRT appeared to provide better OS and LC for patients with malignancies of nasal cavity and paranasal sinuses. A prospective randomized clinical trial is needed to confirm the superiority of CIRT in the treatment of sinonasal tumors., (© 2020 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Background: Proton beam therapy (PBT) with concurrent chemotherapy is promising for esophageal squamous cell carcinoma (ESCC). The aim of study was to evaluate the outcome of concurrent chemo-proton therapy (CCPT), i.e., PBT with concurrent chemotherapy for cT1 ESCC and the salvage endoscopic therapy for local recurrence., Methods: Patients with clinical T1 ESCC who underwent CCPT (60 GyE) between April 2013 and April 2017 at the National Cancer Center Hospital East were investigated. The efficacy of CCPT at the primary site was evaluated via endoscopy; primary complete response (CR) was defined as disappearance of the tumor lesion/ulcer and absence of cancer cells on biopsy. Endoscopic evaluation was performed with the same protocol of conventional chemoradiotherapy. Local recurrence after CCPT was treated with endoscopic resection for cT1a and with esophagectomy or photodynamic therapy for cT1b+., Results: Of the 44 patients (median age, 70 years) that underwent CCPT, 43 patients (98%) achieved primary CR. Among the 44 patients, the 3-year overall survival rate was 95.2%. Five patients (11%) developed local recurrence without regional lymph node or distant metastasis and received endoscopic resection or photodynamic therapy. All five patients were alive with no recurrence after a median 23 months., Conclusions: The results suggest that CCPT is an effective treatment for cT1 ESCC and careful endoscopic follow-up allows preferable local control with salvage endoscopic treatment.

Introduction: Radiotherapy is an established treatment option for prostate cancer (PCa), both as primary treatment and secondary treatment after radical prostatectomy (RP). Since 1998, detailed data on radiotherapy delivered to Swedish men with PCa (e.g. treatment modalities, absorbed doses, fractionation) have been collated within PCa data Base Sweden (PCBaSe). This study reports patterns of radical radiotherapy for PCa in Sweden over the past two decades. Materials and methods: All men with non-metastatic PCa (1998-2016) who received external beam radiotherapy (EBRT) or high or low dose-rate brachytherapy (HDR-BT/LDR-BT) were identified in PCBaSe. Analyses included: trends in radiation techniques, fractionation patterns and total doses over time; PCa-specific survival comparing treatment in 2007-2017 with 1998-2006; and regional variation in type of primary radiotherapy. Results: About 20,876 men underwent primary radiotherapy. The main treatment modalities include conventionally fractionated (2.0 Gy/fraction) EBRT (51%), EBRT with HDR-BT boost (27%) and hypofractionated (>2.4 Gy/fraction) EBRT (11%). EBRT with photon or proton boost and HDR-BT and LDR-BT monotherapies were each used minimally. Use of dose-escalated EBRT (>74 Gy) and moderate hypofractionation increased over time, while use of HDR-BT declined. Considerable regional variation in treatment modalities was apparent. Risk of PCa death following primary radiotherapy had declined for intermediate-risk (HR: 0.60; 95%CI 0.47-0.87) and high-risk PCa (HR: 0.72; 95%CI 0.61-0.86). Discussion: Increased use of dose escalation and hypofractionated EBRT has occurred in Sweden over the past two decades, reflecting current evidence and practice guidelines. Disease-specific outcomes have also improved. Data collected in PCBaSe provide an excellent resource for further research into RT use in PCa management.

The utilization of proton beam therapy (PBT) as the primary treatment of adults with primary brain tumors (APBT) was evaluated through query of the National Cancer Database (NCDB) between the years 2004 and 2015. International Classification of Diseases for Oncology code for each patient was stratified into six histology categories; high-grade gliomas, medulloblastomas, ependymomas, other gliomas, other malignant tumors, or other benign intracranial tumors. Demographics of the treatment population were also analyzed. A total of 1,296 patients received PBT during the 11-year interval for treatment of their primary brain tumor. High-grade glioma, medulloblastoma, ependymoma, other glioma, other malignant, and other benign intracranial histologies made up 39%, 20%, 13%, 12%, 13%, and 2% of the cohort, respectively. The number of patients treated per year increased from 34 to 300 in years 2004 to 2015. Histologies treated with PBT varied over the 11-year interval with high-grade gliomas comprising 75% and 45% at years 2004 and 2015, respectively. The majority of the patient population was 18-29 years of age (59%), Caucasian race (73%), had median reported income of over $63,000 (46%), were privately insured (68%), and were treated at an academic institution (70%). This study characterizes trends of malignant and benign APBT histologies treated with PBT. Our data from 2004 through 2015 illustrates a marked increase in the utilization of PBT in the treatment of APBT and shows variability in the tumor histology treated over this time., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective: To develop prostate cancer-specific physician-hospital networks to define hospital-based units that more accurately group hospitals, providers, and the patients they serve., Methods: Using Surveillance, Epidemiology, and End Results-Medicare, we identified men diagnosed with localized prostate cancer between 2007 and 2011. We created physician-hospital networks by assigning each patient to a physician and each physician to a hospital based on treatment patterns. We assessed content validity by examining characteristics of hospitals anchoring the physician-hospital networks and of the patients associated with these hospitals., Results: We identified 42,963 patients associated with 344 physician-hospital networks. Networks anchored by a teaching hospital (compared to a nonteaching hospital) had higher median numbers of prostate cancer patients (117 [interquartile range {71-189} vs 82 {50-126}]) and treating physicians (7 [4-11] vs 4 [3-6]) (both P <0.001). On average, patients traveled farther to networks anchored by a teaching hospital (49 miles [standard deviation] [207] vs 41 [183]; P <.001). Hospitals known as high-volume centers for robotic prostatectomies, proton-beam therapy, and active surveillance had network rates for these procedures well above the mean. Hospitals known as safety net providers served higher proportions of minorities., Conclusion: We empirically developed prostate-cancer specific physician-hospital networks that exhibit content validity and are relevant from a clinical and policy perspective. They have the potential to become targets for policy interventions focused on improving the delivery of prostate cancer care., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The UK has an important role in the evaluation of proton beam therapy (PBT) and takes its place on the world stage with the opening of the first National Health Service (NHS) PBT centre in Manchester in 2018, and the second in London coming in 2020. Systematic evaluation of the role of PBT is a key objective. By September 2019, 108 patients had started treatment, 60 paediatric, 19 teenagers and young adults and 29 adults. Obtaining robust outcome data is vital, if we are to understand the strengths and weaknesses of current treatment approaches. This is important in demonstrating when PBT will provide an advantage and when it will not, and in quantifying the magnitude of benefit.The UK also has an important part to play in translational PBT research, and building a research capability has always been the vision. We are perfectly placed to perform translational pre-clinical biological and physical experiments in the dedicated research room in Manchester. The nature of DNA damage from proton irradiation is considerably different from X-rays and this needs to be more fully explored. A better understanding is needed of the relative biological effectiveness (RBE) of protons, especially at the end of the Bragg peak, and of the effects on tumour and normal tissue of PBT combined with conventional chemotherapy, targeted drugs and immunomodulatory agents. These experiments can be enhanced by deterministic mathematical models of the molecular and cellular processes of DNA damage response. The fashion of ultra-high dose rate FLASH irradiation also needs to be explored.

Hypofractionated radiotherapy is attractive concerning patient burden and therapy costs, but many aspects play a role when it comes to assess its safety. While exploited for conventional photon therapy and carbon ion therapy, hypofractionation with protons is only rarely applied. One reason for this is uncertainty in the described dose, mainly due to the relative biological effectiveness (RBE), which is small for protons, but not negligible. RBE is generally dose-dependent, and for higher doses as used in hypofractionation, a thorough RBE evaluation is needed. This review article focuses on the RBE variability in protons and associated issues or implications for hypofractionation.

Objective: The Pediatric Proton/Photon Consortium Registry (PPCR) is a comprehensive data registry composed of pediatric patients treated with radiation. It was established to expedite outcomes-based research. The attributes which allow the PPCR to be a successful collaboration are reviewed., Methods and Materials: Current eligibility criteria are radiotherapy patients < 22 years treated at one of the 15 US participating institutions. Detailed health and treatment data are collected about the disease presentation and treatment exposures, and annually thereafter, in REDCap (Research Electronic Data Capture). DICOM (Digital Imaging and Communications in Medicine) imaging and radiation plans are collected through MIM/MIMcloud. An optional patient-reported quality-of-life (PedsQL) study is administered at 10 sites., Results: Accrual started October 2012 with 2,775 participants enrolled as of 25 July 2019. Most patients, 62.0%, were treated for central nervous system (CNS) tumors, the most common of which are medulloblastoma ( n = 349), ependymoma ( n = 309), and glial/astrocytoma tumors ( n = 279). The most common non-CNS diagnoses are rhabdomyosarcoma ( n = 284), Ewing's sarcoma ( n = 153), and neuroblastoma ( n = 130). While the majority of participants are US residents, 18.7% come from 36 other countries. Over 685 patients participate in the PedsQL study., Conclusions: The PPCR is a valuable research platform capable of answering countless research questions that will ultimately improve patient care. Centers outside of the USA are invited to participate directly or may engage with the PPCR to align data collection strategies to facilitate large-scale international research., Advances in Knowledge: For investigators looking to carry out research in a large pediatric oncology cohort or interested in registry work, this paper provides an updated overview of the PPCR.

Objective: To quantify how a control software upgrade changed beam delivery times and impacted efficiency and capacity of a multiroom proton therapy center., Methods: A four-room center treating approximately 90 patients/day, treating for approximately 7 years with optimized operations, underwent a software upgrade which reduced room and energy switching times from approximately 30 to 20 s and approximately 4 s to ~0.5 s, respectively. The center uses radio-frequency identification data to track patient treatments and has software which links this to beam delivery data extracted from the treatment log server. Two 4-month periods, with comparable patient volume, representing periods before and after the software change, were retrospectively analyzed., Results: A total of 16,168 and 17,102 fields were analyzed. For bilateral head and neck and prostate patients, the beam waiting time was reduced by nearly a factor of 3 and the beam delivery times were reduced by nearly a factor of 2.5. Room switching times were reduced more modestly. Gantry capacity has increased from approximately 30 patients to 40-45 patients in a 16-h daily operation., Conclusions: Many proton centers are striving for increased efficiencies. We demonstrated that reductions in energy and room switching time can significantly increase center capacity. Greater potential for further gains would come from improvements in setup and imaging efficiency., Advances in Knowledge: This paper provides detailed measured data on the effect on treatment times resulting from reducing energy and room switching times under controlled conditions. It helps validate the models of previous investigations to establish treatment capacity of a proton therapy center.

Owing to the favorable physical and biological properties of swift ions in matter, their application to radiation therapy for highly selective cancer treatment is rapidly spreading worldwide. To date, over 90 ion therapy facilities are operational, predominantly with proton beams, and about the same amount is under construction or planning.Over the last decades, considerable developments have been achieved in accelerator technology, beam delivery and medical physics to enhance conformation of the dose delivery to complex shaped tumor volumes, with excellent sparing of surrounding normal tissue and critical organs. Nevertheless, full clinical exploitation of the ion beam advantages is still challenged, especially by uncertainties in the knowledge of the beam range in the actual patient anatomy during the fractionated course of treatment, thus calling for continued multidisciplinary research in this rapidly emerging field.This contribution will review latest developments aiming to image the patient with the same beam quality as for therapy prior to treatment, and to visualize in-vivo the treatment delivery by exploiting irradiation-induced physical emissions, with different level of maturity from proof-of-concept studies in phantoms and first in-silico studies up to clinical testing and initial clinical evaluation.

Purpose: Prior authorization (PA) has been widely implemented for proton beam therapy (PBT). We sought to determine the association between PA determination and patient characteristics, practice guidelines, and potential treatment delays., Methods and Materials: A single-institution retrospective analysis was performed of all patients considered for PBT between 2015 and 2018 at a National Cancer Institute-designated Comprehensive Cancer Center. Differences in treatment start times and denial rates over time were compared, and multivariable logistic regression was used to identify predictors of initial denial., Results: A total of 444 patients were considered for PBT, including 396 adult and 48 pediatric patients. The American Society for Radiation Oncology model policy supported PBT coverage for 77% of the cohort. Of adult patients requiring PA, 64% were initially denied and 32% remained denied after appeal. In patients considered for reirradiation or randomized phase 3 trial enrollment, initial denial rates were 57% and 64%, respectively. Insurance coverage was not related to diagnosis, reirradiation, trial enrollment, or the American Society for Radiation Oncology model policy guidelines, but it was related to insurance category on multivariable analysis (P < .001). Over a 3-year timespan, initial denial rates increased from 55% to 74% (P = .034). PA delayed treatment start by an average of 3 weeks (and up to 4 months) for those requiring appeal (P < .001) and resulted in 19% of denied patients abandoning radiation treatment altogether. Of pediatric patients, 9% were initially denied, all of whom were approved after appeal, and PA requirement did not delay treatment start (P = .47)., Conclusions: PA requirements in adults represent a significant burden in initiating PBT and cause significant delays in patient care. Insurance approval is arbitrary and has become more restrictive over time, discordant with national clinical practice guidelines. Payors and providers should seek to streamline coverage policies in alignment with established guidelines to ensure appropriate and timely patient care., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To quantify the effects of opening a proton center (PC) on an academic medical center (AMC)/radiation oncology department., Methods and Materials: Radiation treatment volume and relative value units from fiscal year 2015 (FY15) to FY17 were retrospectively analyzed at the AMC and 2 community-based centers. To quantify new patient referrals to the AMC, we reviewed the electronic medical record for all patients seen at the PC since consults were initiated in November 2015 (n = 1173). Patients were excluded if the date of entry into the AMC electronic medical record predated their PC consultation. Hospital resource use and professional and technical charges were obtained for these patients. Academic growth, philanthropy, and resident education were evaluated based on grant submissions, clinical trial enrollment, philanthropy, and pediatric case exposure, respectively, from PC opening through FY17., Results: From FY15 to FY17, radiation fractions at the AMC and the 2 community sites decreased by 14% (95% confidence interval [CI], 12%-16%, P < .001) and increased by 19% (95% CI, 16%-23%, P < .001) and 2% (95% CI, -1.1 to 4.3%, P = NS), respectively; the number of new starts decreased by 3% (95% CI, -13% to 7%, P = NS) and 2% (95% CI, -20% to 16%, P = NS) and increased by 13% (95% CI -2% to 27%, P = NS), respectively. At the AMC, technical and professional relative value units decreased by 5% and 14%, respectively. The PC made 561 external referrals to the AMC, which resulted in $2.38 million technical and $2.13 million professional charges at the AMC. Fifteen grant submissions ($12.83 million) resulted in 6 awards ($3.26 million). Twenty-two clinical trials involving proton therapy were opened, on which a total of 5% (n = 54) of patients enrolled during calendar years 2017 and 2018. The PC was involved in gift donations of $1.6 million. There was a nonsignificant 37% increase in number of pediatric cases., Conclusions: Despite a slight decline in AMC photon patient volumes and relative value units, a positive downstream effect was associated with the addition of a PC, which benefited the AMC., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: Proton therapy is increasingly prescribed for cancer treatment, given its potential for improvements in clinical outcomes and toxicity reduction; however, insurance coverage continues to be a barrier to patient access. This study examined insurance approval and appeal outcomes at a large-volume proton therapy center to clarify the process and identify areas for improvement., Methods and Materials: In 2013 to 2016, 1753 patients with thoracic or head and neck cancer were considered for proton therapy; 903 (553 thoracic, 350 head and neck) entered the insurance process. Rates of and times to approval and successful appeal after initial denial were calculated. Clinical factors were evaluated for association with insurance outcomes via logistic regression., Results: Approval rates by Medicare (n = 538) and private insurance (n = 365) were 91% and 30% on initial request, at a median 3 days and 14 days from inquiry to determination. Of the 306 patients initially denied coverage, 276 appealed the decision, and denial was overturned for 189 patients (68%; median time, 21 days from initial inquiry). On multivariable analysis, Medicare (odds ratio [OR], 14.20; P < .001) was the strongest predictor of initial approval. Approval rates decreased from 2013 to 2014 versus 2015 to 2016 (OR 0.54; P = .001). For patients who appealed denial, multivariable analysis found no associations between approval and trial enrollment or tumor type. Submission of a comparison treatment plan (proton vs photon) indicating dosimetric advantage to normal tissues was associated with decreased likelihood of approval (OR 0.43; P = .006), as was a prescribed dose of ≥66 Gy (OR 0.48; P = .019)., Conclusions: Despite an 87% ultimate approval rate for proton therapy, the insurance process is a resource-intensive barrier to patient access associated with significant time delays to cancer treatment. These findings, plus the lack of clinical correlates with insurance outcomes, highlight a need for increased efficiency, transparency, and collaboration among stakeholders to promote timely patient care and research., (Copyright © 2018. Published by Elsevier Inc.)

Objective: Thymic malignancies (TM) are rare tumors with long-term survivorship, causing concerns for radiotherapy-related late side effects. Proton therapy (PT) reduces the radiation dose to organs at risk, potentially decreasing long-term toxicities while preserving disease control. We report patterns-of-care and early clinical outcomes after PT for thymoma and thymic carcinoma. Methods: Between January 2008 and March 2017, 30 patients with TMs enrolled on one of two IRB-approved prospective protocols and received postoperative or definitive PT. Clinical outcomes, pathology, treatment dose, toxicities, and follow-up information were analyzed. Results: Twenty-two thymoma patients with a median age of 52.1 years (range, 23-72) received a median RT dose of 54 Gy (RBE) (range, 45-70) either postoperatively (91%) or definitively (9%); 23% received adjuvant chemotherapy. Among eight thymic carcinoma patients, the median age was 65.5 years (range, 38-88) and median RT dose was 60 Gy (RBE) (range, 42-70) delivered postoperatively (75%) or definitively (25%); 50% received chemotherapy. Median follow-up for all patients was 13 months (range, 2-59 months). Five patients relapsed, one locally (3%). Three patients died of disease progression, including two thymomas and one thymic carcinoma patient; a fourth died of intercurrent disease. One patient with thymic carcinoma and 1 with thymoma are alive with disease. No patients treated with PT for their initial disease (de novo) experienced grade ≥3 toxicities. The most common grade 2 toxicities were dermatitis (37%), cough (13%), and esophagitis (10%). Conclusion: Adjuvant and definitive PT are being used in the treatment of TMs. Early results of the largest such cohort reported to date demonstrates an acceptable rate of recurrence with a favorable toxicity profile. Longer follow-up and a larger patient cohort are needed to confirm these findings.

Purpose: Consistent follow-up and data collection are necessary to identify long-term benefits/detriments of proton radiotherapy. Obtaining comprehensive clinical follow-up can be difficult and time-intensive for proton centers. Here we evaluate what factors affect maximum follow-up time among MGH Pediatric Proton Consortium Registry (PPCR) participants., Patients and Methods: Enrollment in the PPCR was offered to any patient <22 years receiving protons. Patients were excluded from analysis if they were taken off study due to death or withdrawal. Distance from MGH was calculated by the great-circle formula. We utilized both univariate and multivariate analyses to determine risk factors associated with follow-up time., Results: 333 PPCR patients enrolled between 10/2012 and 03/2017 were included. Median follow-up was 2.4 years (<1-5.5), and median distance away from the proton center was 256.4 km (<1.6-16,949.6). Distance from MGH significantly predicted follow-up time: patients living outside the Boston Metropolitan Statistical Area, >121 km from the proton center, had average follow-up that was 0.53 years less compared to those living within 121 km (p = 0.0002). Loss in average follow-up was also associated with Medicaid insurance, treatment delay due to insurance, and non-White race. Those co-enrolled on a proton trial or seen at a facility had significantly increased follow-up by almost one year (p < 0.0001)., Conclusion: Patients living further from treating proton center have shorter follow-up durations. Increased distance from treating centers may adversely affect clinical outcomes research. Enhanced sharing of medical information among care providers and improved collection methods are needed to effectively evaluate the benefits of proton therapy., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: To help guide individualized treatment, we sought to identify baseline predictive factors that impact long-term erectile function following high-dose image-guided radiotherapy (HD-IGRT)., Methods: Potent men with localized prostate cancer treated with radiotherapy alone were enrolled in an institutional review board-approved prospective cohort study. Men received HD-IGRT as primary treatment of prostate cancer. Patient-reported inventories were used to assess erectile function at baseline, 6 months, 2 years, and 5 years after treatment. Long-term potency rates were compared to validated models, and baseline factors were used to create a novel, internally validated nomogram for predicting long-term function., Results: 1,159 men were treated with HD-IGRT. Among 676 men who were potent at baseline and did not receive hormone therapy, the potency rates at 6 months, 2 years, and 5 years were 81%, 68%, and 61%. Recursive partitioning categorized patients into 3 groups based on two factors: baseline response to EPIC Q57 (ability to have an erection) and pre-existing heart disease. At 5 years, the most favorable group reported "very good" on Q57 and had an 80% potency rate (n = 137; p = 0.83); the intermediate group reported "good" on Q57 and had no baseline cardiac disease with a 62% potency rate (n = 145; p = 0.86); and the remaining poor risk group had a 37% potency rate (n = 117; p = 0.19)., Conclusions: Patient-reported pretreatment sexual function and comorbidities enables stratification and prediction of erectile function. EPIC subset questions with baseline comorbidities may potentially serve as a quick and practical clinical tool for predicting sexual survivorship., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Purpose: Recent trends, including the use of proton therapy and administration of reduced doses of cyclophosphamide, have been adapted in head and neck (HN) rhabdomyosarcoma (RMS) to reduce late morbidity. Our primary goal was to analyze local control and survival outcomes after photon versus proton irradiation in pediatric patients with HN-RMS, with the secondary goal of analyzing the effect of cyclophosphamide dose on disease outcomes., Methods and Materials: This single-institution cohort study comprised 76 pediatric HN-RMS patients treated with definitive chemoradiation from 2000 to 2018. Fifty-one patients (67%) received intensity modulated photon radiation therapy, and 25 (33%) received proton therapy., Results: Local failure (LF) at 2 years was 12.5% for parameningeal RMS and 0% for orbital RMS and other head and neck sites (P = .24). Patients treated with protons were more likely to have received reduced-dose cyclophosphamide (P < .0001). The 2-year LF was 7.9% in the intensity modulated photon radiation therapy cohort versus 14.6% in the proton cohort (P = .07), with no difference in survival outcomes. Cumulative cyclophosphamide dose was significantly associated with 2-year LF: 0% for cumulative dose of >20 g/m 2 versus 15.3% for ≤20 g/m 2 (P = .04). In parameningeal RMS patients (n = 59), both cumulative cyclophosphamide dose and dose intensity were associated with LF (P = .01). There was a trend toward worse event-free survival for parameningeal RMS patients who received reduced-dose-intensity cyclophosphamide (59.2% vs 70.6%, P = .11)., Conclusions: Both dose-intensity and cumulative cyclophosphamide dose seem to play an important role in achieving local control for HN-RMS patients treated with either protons or photons. Longer follow-up is needed to further assess disease outcomes with proton therapy., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To facilitate the initiation of observational studies on late effects of proton therapy in pediatric patients, we report on current patterns of proton therapy use worldwide in patients aged less than 22 years., Materials & Methods: Fifty-four proton centers treating pediatric patients in 2016 in 11 countries were invited to respond to a survey about the number of patients treated during that year by age group, intent of treatment, delivery technique and tumor types., Results: Among the 40 participating centers (participation rate: 74%), a total of 1,860 patients were treated in 2016 (North America: 1205, Europe: 432, Asia: 223). The numbers of patients per center ranged from 1 to 206 (median: 29). Twenty-four percent of the patients were <5 years of age, and 50% <10 years. More than 30 pediatric tumor types were identified, mainly treated with curative intent: 48% were CNS, 25% extra-cranial sarcomas, 7% neuroblastoma, and 5% hematopoietic tumors. About half of the patients were treated with pencil beam scanning. Treatment patterns were broadly similar across the three continents., Conclusion: To our knowledge, this survey provides the first worldwide assessment of proton therapy use for pediatric cancer management. Since previous estimates in the United States and Europe, CNS tumors remain the cancer types most commonly treated with protons in 2016. However, the proportion of extra-cranial tumors is growing worldwide. The typically low numbers of patients treated in each center indicate the need for international research collaborations to assess long-term outcomes of proton therapy in pediatric patients., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The purpose of this work was to develop an end-to-end patient-specific quality assurance (QA) technique for spot-scanned proton therapy that is more sensitive and efficient than traditional approaches. The patient-specific methodology relies on independently verifying the accuracy of the delivered proton fluence and the dose calculation in the heterogeneous patient volume. A Monte Carlo dose calculation engine, which was developed in-house, recalculates a planned dose distribution on the patient CT data set to verify the dose distribution represented by the treatment planning system. The plan is then delivered in a pre-treatment setting and logs of spot position and dose monitors, which are integrated into the treatment nozzle, are recorded. A computational routine compares the delivery log to the DICOM spot map used by the Monte Carlo calculation to ensure that the delivered parameters at the machine match the calculated plan. Measurements of dose planes using independent detector arrays, which historically are the standard approach to patient-specific QA, are not performed for every patient. The nozzle-integrated detectors are rigorously validated using independent detectors in regular QA intervals. The measured data are compared to the expected delivery patterns. The dose monitor reading deviations are reported in a histogram, while the spot position discrepancies are plotted vs. spot number to facilitate independent analysis of both random and systematic deviations. Action thresholds are linked to accuracy of the commissioned delivery system. Even when plan delivery is acceptable, the Monte Carlo second check system has identified dose calculation issues which would not have been illuminated using traditional, phantom-based measurement techniques. The efficiency and sensitivity of our patient-specific QA program has been improved by implementing a procedure which independently verifies patient dose calculation accuracy and plan delivery fidelity. Such an approach to QA requires holistic integration and maintenance of patient-specific and patient-independent QA., Competing Interests: The authors have declared that no competing interests exist.

Objectives: To examine patterns of care associated with the administration of proton versus photon therapy for adult patients with primary brain tumors in a large national cohort from the United States., Methods: The National Cancer Database (NCDB) was queried for newly diagnosed primary brain tumors (2004-2014) in adult patients aged 18 and older receiving proton or photon radiotherapy. Clinical features, patient demographics and treatment parameters were extracted. Differences between groups were assessed using multivariable logistic regression analysis., Results: In total, 73,073 patients were analyzed (n = 72,635 [99.4%] photon therapy, n = 438 [0.6%] proton therapy). On multivariable analysis of photon versus proton therapy, several factors predicted for receipt of proton therapy, including younger age (p = .041), highest income quartile (p = .007), treatment at academic institutions (p < .001), in regional facilities outside the Midwest/South (p < .001), diagnosis in more recent years (p = .003), fewer comorbidities (p < .001) and non-glioblastoma histology (p < .001)., Conclusions: There are several significant socioeconomic variables that influence receipt of proton therapy for primary brain tumors. Although not implying causation, the socioeconomic findings discovered herein should be taken into account when delivering cancer care to all patients.

The use of proton therapy as a treatment modality is becoming more widespread in conventional radiation therapy practice. Commercialisation and introduction of compact systems has led to embedding of proton therapy facilities in existing hospital environments. In addition, technologically, proton therapy is currently undergoing an important evolution, moving from passive scattering delivery techniques to active pencil beam scanning, adopting image guidance techniques from conventional radiotherapy and introducing various range verification techniques in the clinic. An overview is given of today's technological evolution of proton therapy in clinical environments, and its impact on aspects of radiation protection.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death, as few patients can be treated with currently available curative local modalities. In patients with HCC where curative modalities are not feasible, radiation therapy (RT) has emerged as an alternative or combination therapy. With the development of various technologies, RT has been increasingly used for the management of HCC. Among these advances, proton beam therapy (PBT) has several unique physical properties that give it a finite range in a distal direction, and thus no exit dose along the beam path. Therefore, PBT has dosimetric advantages compared with X-ray therapy for the treatment of HCC. Indeed, various reports in the literature have described the favorable clinical outcomes and improved safety of PBT for HCC patients compared with X-ray therapy. However, there are some technical issues regarding the use of PBT in HCC, including uncertainty of organ motion and inaccuracy during calculation of tissue density and beam range, all of which may reduce the robustness of a PBT treatment plan. In this review, we discuss the physical properties, current clinical data, technical issues, and future perspectives on PBT for the treatment of HCC.

Purpose: To analyze effects of closure of an academic proton treatment center (PTC) on pediatric case volume, distribution, and resident education., Methods and Materials: This was a review of 412 consecutive pediatric (age ≤18 years) cases treated at a single institution from 2012 to 2016. Residents' Accreditation Council for Graduate Medical Education case logs for the same years were also analyzed. Characteristics of the patient population and resident case volumes before and after closure of the PTC are reported., Results: Overall pediatric new starts declined by approximately 50%, from 35 to 70 per 6 months in 2012 to 2014 to 22 to 30 per 6 months in 2015 to 2016. Central nervous system (CNS) case volume declined sharply, from 121 patients treated in 2012 to 2015 to 18 patients in 2015 to 2016. In 2012 to 2014 our institution treated 36, 24, and 17 patients for medulloblastoma/intracranial primitive neuroectodermal tumor, ependymoma, and low-grade glioma, respectively, compared with 0, 1, and 1 patient(s) in 2015 to 2016. Forty-nine patients were treated with craniospinal radiation (CSI) from 2012 to 2014, whereas only 2 patients underwent CSI between 2015 and 2016. Hematologic malignancy patient volume and use of total body irradiation remained relatively stable. Patients treated when the PTC was open were significantly younger (9.1 vs 10.7 years, P=.010) and their radiation courses were longer (35.4 vs 20.9 days, P<.0001) than those treated after its closure. Resident case logs showed only a small decline in total pediatric cases, because the percentage of pediatric cases covered by residents increased after PTC closure; however, residents logged fewer CNS cases after PTC closure versus before., Conclusions: Overall pediatric case volume decreased after PTC closure, as did the number of patients treated for potentially curable CNS tumors. Our findings raise important questions regarding resident training in pediatric radiation oncology as these cases become increasingly concentrated at specialized centers., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: To characterize the changes in the use of radiation therapy (RT), specifically proton beam radiation therapy (PBRT), among adult and pediatric patients over a 11-year period in a very large population of insured patients., Methods and Materials: We conducted a retrospective analysis of the OptumLabs Data Warehouse claims database of more than 100 million insured US enrollees. Descriptive analyses were undertaken to evaluate the characteristics of patients receiving RT from 2002 to 2012., Results: There were 474,533 patients treated with RT from 2002 to 2012. The percentage of patients treated with 3-dimensional conformal radiation therapy, 2-dimensional RT/brachytherapy, intensity modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT), and PBRT was 34.5%, 63.4%, 2.1%, 0.0%, and 0.1% and 40.4%, 36.0%, 21.9%, 1.1%, and 0.6% in 2002 and 2012, respectively. The greatest increase in utilization was of IMRT for prostate cancer, growing from 3.5% to 64.0%. For non-prostate cancer adults, IMRT use grew from 1.7% to 16.4%. For children, PBRT utilization increased from 0.3% to 9.7%. For prostate cancer patients, PBRT increased from 0.0% to 2.6%. For all patients, advanced technology (SBRT and PBRT) use was very low at <2%, versus 22% for IMRT., Conclusions: This is the largest and most geographically diverse description of RT utilization. Proton beam RT utilization remains very low and has had little impact on overall RT utilization compared with IMRT. The largest shift has occurred in IMRT for prostate cancer. Our findings indicate that overall utilization of proton therapy has been low and that its use has likely had little impact on national expenditures on cancer care in the current environment., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Proton radiotherapy remains a limited resource despite its clear potential for reducing radiation doses to normal tissues and late effects in children in comparison with photon therapy. This study examined the impact of race and socioeconomic factors on the use of proton therapy in children with solid malignancies., Methods: This study evaluated 12,101 children (age ≤ 21 years) in the National Cancer Data Base who had been diagnosed with a solid malignancy between 2004 and 2013 and had received photon- or proton-based radiotherapy. Logistic regression analysis was used to evaluate patient, tumor, and socioeconomic variables affecting treatment with proton radiotherapy versus photon radiotherapy., Results: Eight percent of the patients in the entire cohort received proton radiotherapy, and this proportion increased between 2004 (1.7%) and 2013 (17.5%). Proton therapy was more frequently used in younger patients (age ≤ 10 years; odds ratio [OR], 1.9; 95% confidence interval [CI], 1.6-2.2) and in patients with bone/joint primaries and ependymoma, medulloblastoma, and rhabdomyosarcoma histologies (P < .05). Patients with metastatic disease were less likely to receive proton therapy (OR, 0.4; 95% CI, 0.3-0.6). Patients with private/managed care were more likely than patients with Medicaid or no insurance to receive proton therapy (P < .0001). A higher median household income and educational attainment were also associated with increased proton use (P < .001). Patients treated with proton therapy versus photon therapy were more likely to travel more than 200 miles (13% vs 5%; P < .0001)., Conclusions: Socioeconomic factors affect the use of proton radiotherapy in children. Whether this disparity is related to differences in the referral patterns, the knowledge of treatment modalities, or the ability to travel for therapy needs to be further clarified. Improving access to proton therapy in underserved pediatric populations is essential. Cancer 2017;123:4048-56. © 2017 American Cancer Society., (© 2017 American Cancer Society.)

Background: We performed a survey using the modified EORTC Facility questionnaire (pFQ) to evaluate the human, technical and organizational resources of particle centers in Europe., Material and Methods: The modified pFQ consisted of 235 questions distributed in 11 sections accessible on line on an EORTC server. Fifteen centers from 8 countries completed the pFQ between May 2015 and December 2015., Results: The average number of patients treated per year and per particle center was 221 (range, 40-557). The majority (66.7%) of centers had pencil beam or raster scanning capability. Four (27%) centers were dedicated to eye treatment only. An increase in the patients-health professional FTE ratio was observed for eye tumor only centers when compared to other centers. All centers treated routinely chordomas/chondrosarcomas, brain tumors and sarcomas but rarely breast cancer. The majority of centers treated pediatric cases with particles. Only a minority of the queried institutions treated non-static targets., Conclusions: As the number of particle centers coming online will increase, the experience with this treatment modality will rise in Europe. Children can currently be treated in these facilities in a majority of cases. The majority of these centers provide state of the art particle beam therapy., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Despite enthusiasm for advanced radiation technologies, understanding of their adoption in recent years is limited. The aim of this study was to elucidate utilization trends of conventional radiation, intensity-modulated radiotherapy (IMRT), brachytherapy, proton radiotherapy, stereotactic body radiotherapy (SBRT), and stereotactic radiosurgery (SRS) using a large convenience sample of irradiated patients with cancer identified from private insurance claims in the United States. The unit of analysis was a claim corresponding to a fraction of delivered radiotherapy from 2008 to 2014. Each claim was assigned a disease site on the basis of the diagnosis code and a radiation technology on the basis of the procedure code. In 2014, conventional radiation and IMRT constituted 56% and 39% of all radiation treatment claims, respectively, while brachytherapy constituted 2%, proton radiotherapy 1%, SBRT 1%, and SRS <1%. Compared with the first quarter of 2008, the proportional contribution of conventional radiation and brachytherapy to all radiation claims each decreased by 16% in the fourth quarter of 2014. In contrast, proportional contribution increased by 32% for IMRT, 83% for proton radiotherapy, 124% for SRS, and 309% for SBRT. Prostate cancer constituted 60% of all proton claims in 2008 but declined to 37% by 2014. SBRT was used to treat a variety of disease sites, most commonly primary lung (25%), prostate (12%), secondary bone (9%), and secondary lung (9%), in 2014. In this claims-based analysis of younger patients with private insurance, conventional radiation and IMRT were the most commonly used technologies from 2008 to 2014, while SBRT showed the most robust growth over the study period., (Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate usage trends and identify factors associated with proton beam therapy (PBT) compared to alternative forms of external beam radiation therapy (RT) (EBRT) for localized prostate cancer., Patients and Methods: The National Cancer Database was queried for men with localized (N0, M0) prostate cancer diagnosed between 2004 and 2013, treated with EBRT, with available data on EBRT modality (photon vs. PBT). Binary multiple logistic regression identified variables associated with EBRT modality., Results: In total, 143,702 patients were evaluated with relatively few men receiving PBT (5,709 [4.0%]). Significant differences in patient and clinical characteristics were identified between those men treated with PBT compared to those treated with photon (odds ratio [OR]; 95% CI). Patients treated with PBT were generally younger (OR = 0.73; CI: 0.67-0.82), National Comprehensive Cancer Network low-risk compared to intermediate (0.71; 0.65-0.78) or high (0.44; 0.38-0.5) risk, white vs. black race (0.66; 0.58-0.77), with less comorbidity (Charlson-Deyo 0 vs. 2+; 0.70; 0.50-0.98), live in higher income counties (1.55; 1.36-1.78), and live in metropolitan areas compared to urban (0.21; 0.18-0.23) or rural (0.14; 0.10-0.19) areas. Most patients treated with PBT travelled more than 100 miles to the treatment facility. Annual PBT utilization significantly increased in both total number and percentage of EBRT over time (2.7%-5.6%; P<0.001). PBT utilization increased mostly in men classified as National Comprehensive Cancer Network low-risk (4%-10.2%)., Conclusion: PBT for men with localized prostate cancer significantly increased in the United States from 2004 to 2013. Significant demographic and prognostic differences between those men treated with photons and protons were identified., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: To retrospectively analyze the treatment outcomes of particle therapy using protons or carbon ions for unresectable or incompletely resected bone and soft tissue sarcomas (BSTSs) of the pelvis., Methods and Materials: From May 2005 to December 2014, 91 patients with nonmetastatic histologically proven unresectable or incompletely resected pelvic BSTSs underwent particle therapy with curative intent. The particle therapy used protons (52 patients) or carbon ions (39 patients). All patients received a dose of 70.4 Gy (relative biologic effectiveness) in 32 fractions (55 patients) or 16 fractions (36 patients)., Results: The median patient age was 67 years (range 18-87). The median planning target volume (PTV) was 455 cm 3 (range 108-1984). The histologic type was chordoma in 53 patients, chondrosarcoma in 14, osteosarcoma in 10, malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma in 5, and other in 9 patients. Of the 91 patients, 82 had a primary tumor and 9 a recurrent tumor. The median follow-up period was 32 months (range 3-112). The 3-year rate of overall survival (OS), progression-free survival (PFS), and local control was 83%, 72%, and 92%, respectively. A Cox proportional hazards model revealed that chordoma histologic features and a PTV of ≤500 cm 3 were significantly associated with better OS, and a primary tumor and PTV of ≤500 cm 3 were significantly associated with better PFS. Ion type and number of fractions were not significantly associated with OS, PFS, or local control. Late grade ≥3 toxicities were observed in 23 patients. Compared with the 32-fraction protocol, the 16-fraction protocol was associated with significantly more frequent late grade ≥3 toxicities (18 of 36 vs 5 of 55; P<.001)., Conclusions: Particle therapy using protons or carbon ions was effective for unresectable or incompletely resected pelvic BSTS, and the 32-fraction protocol was effective and relatively less toxic. Nevertheless, a longer follow-up period is needed to confirm these results., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: The study aims to perform joint estimation of the risk of recurrence caused by inadequate radiation dose coverage of lymph node targets and the risk of cardiac toxicity caused by radiation exposure to the heart. Delivered photon plans are compared with realistic proton plans, thereby providing evidence-based estimates of the heterogeneity of treatment effects in consecutive cases for the 2 radiation treatment modalities., Methods and Materials: Forty-one patients referred for postlumpectomy comprehensive nodal photon irradiation for left-sided breast cancer were included. Comparative proton plans were optimized by a spot scanning technique with single-field optimization from 2 en face beams. Cardiotoxicity risk was estimated with the model of Darby et al, and risk of recurrence following a compromise of lymph node coverage was estimated by a linear dose-response model fitted to the recurrence data from the recently published EORTC (European Organisation for Research and Treatment of Cancer) 22922/10925 and NCIC-CTG (National Cancer Institute of Canada Clinical Trials Group) MA.20 randomized controlled trials., Results: Excess absolute risk of cardiac morbidity was small with photon therapy at an attained age of 80 years, with median values of 1.0% (range, 0.2%-2.9%) and 0.5% (range, 0.03%-1.0%) with and without cardiac risk factors, respectively, but even lower with proton therapy (0.13% [range, 0.02%-0.5%] and 0.06% [range, 0.004%-0.3%], respectively). The median estimated excess absolute risk of breast cancer recurrence after 10 years was 0.10% (range, 0.0%-0.9%) with photons and 0.02% (range, 0.0%-0.07%) with protons. The association between age of the patient and benefit from proton therapy was weak, almost non-existing (Spearman rank correlations of -0.15 and -0.30 with and without cardiac risk factors, respectively)., Conclusions: Modern photon therapy yields limited risk of cardiac toxicity in most patients, but proton therapy can reduce the predicted risk of cardiac toxicity by up to 2.9% and the risk of breast cancer recurrence by 0.9% in individual patients. Predicted benefit correlates weakly with age. Combined assessment of the risk from cardiac exposure and inadequate target coverage is desirable for rational consideration of competing photon and proton therapy plans., (Copyright © 2016. Published by Elsevier Inc.)

Purpose: To review and assess ongoing proton beam therapy (PBT) clinical trials and to identify major gaps., Methods and Materials: Active PBT clinical trials were identified from clinicaltrials.gov and the World Health Organization International Clinical Trials Platform Registry. Data on clinical trial disease site, age group, projected patient enrollment, expected start and end dates, study type, and funding source were extracted., Results: A total of 122 active PBT clinical trials were identified, with target enrollment of >42,000 patients worldwide. Ninety-six trials (79%), with a median planned sample size of 68, were classified as interventional studies. Observational studies accounted for 21% of trials but 71% (n=29,852) of planned patient enrollment. The most common PBT clinical trials focus on gastrointestinal tract tumors (21%, n=26), tumors of the central nervous system (15%, n=18), and prostate cancer (12%, n=15). Five active studies (lung, esophagus, head and neck, prostate, breast) will randomize patients between protons and photons, and 3 will randomize patients between protons and carbon ion therapy., Conclusions: The PBT clinical trial portfolio is expanding rapidly. Although the majority of ongoing studies are interventional, the majority of patients will be accrued to observational studies. Future efforts should focus on strategies to encourage optimal patient enrollment and retention, with an emphasis on randomized, controlled trials, which will require support from third-party payers. Results of ongoing PBT studies should be evaluated in terms of comparative effectiveness, as well as incremental effectiveness and value offered by PBT in comparison with conventional radiation modalities., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: Proton beam therapy (PBT) potentially allows for improved sparing of normal tissues, hopefully leading to decreased late side effects in children. Using a national registry, we sought to perform a patterns-of-care analysis for children receiving PBT for primary malignancies of the central nervous system (CNS)., Methods and Materials: Using the National Cancer Data Base, we identified pediatric patients with primary CNS malignancies that were diagnosed between 2004 and 2012. We used a standard t test for comparison of means and χ 2 testing to identify differences in demographic and clinical characteristics. Univariate and multivariate logistical regression was applied to identify predictors of PBT use., Results: We identified 4637 pediatric patients receiving radiation therapy from 2004 to 2012, including a subset of 267 patients treated with PBT. We found that PBT use increased with time from <1% in 2004 to 15% in 2012. In multivariate logistical regression, we found the following to be predictors of receipt of PBT: private insurance, the highest income bracket, younger age, living in a metropolitan area, and residing >200 miles from a radiation treatment facility (P<.05)., Conclusions: We noted the proportion of children receiving PBT to be significantly increasing over time from <1% to 15% from 2004 to 2012. We also observed important disparities in receipt of PBT based on socioeconomic status. Children from higher-income households and with private insurance were more likely to use this expensive technology. As we continue to demonstrate the potential benefits of PBT in children, efforts are needed to expand the accessibility of PBT for children of all socioeconomic backgrounds and regions of the country., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To analyze outcomes and predictors associated with proton radiation therapy for non-small cell lung cancer (NSCLC) in the National Cancer Database., Methods and Materials: The National Cancer Database was queried to capture patients with stage I-IV NSCLC treated with thoracic radiation from 2004 to 2012. A logistic regression model was used to determine the predictors for utilization of proton radiation therapy. The univariate and multivariable association with overall survival were assessed by Cox proportional hazards models along with log-rank tests. A propensity score matching method was implemented to balance baseline covariates and eliminate selection bias., Results: A total of 243,822 patients (photon radiation therapy: 243,474; proton radiation therapy: 348) were included in the analysis. Patients in a ZIP code with a median income of <$46,000 per year were less likely to receive proton treatment, with the income cohort of $30,000 to $35,999 least likely to receive proton therapy (odds ratio 0.63 [95% confidence interval (CI) 0.44-0.90]; P=.011). On multivariate analysis of all patients, non-proton therapy was associated with significantly worse survival compared with proton therapy (hazard ratio 1.21 [95% CI 1.06-1.39]; P<.01). On propensity matched analysis, proton radiation therapy (n=309) was associated with better 5-year overall survival compared with non-proton radiation therapy (n=1549), 22% versus 16% (P=.025). For stage II and III patients, non-proton radiation therapy was associated with worse survival compared with proton radiation therapy (hazard ratio 1.35 [95% CI 1.10-1.64], P<.01)., Conclusions: Thoracic radiation with protons is associated with better survival in this retrospective analysis; further validation in the randomized setting is needed to account for any imbalances in patient characteristics, including positron emission tomography-computed tomography staging., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to verify acquisition feasibility of a single photon emission computed tomography image using prompt gamma rays for proton boron fusion therapy (PBFT) and to confirm an enhanced therapeutic effect of PBFT by comparison with conventional proton therapy without use of boron., Methods: Monte Carlo simulation was performed to acquire reconstructed image during PBFT. We acquired percentage depth dose (PDD) of the proton beams in a water phantom, energy spectrum of the prompt gamma rays, and tomographic images, including the boron uptake region (BUR; target). The prompt gamma ray image was reconstructed using maximum likelihood expectation maximisation (MLEM) with 64 projection raw data. To verify the reconstructed image, both an image profile and contrast analysis according to the iteration number were conducted. In addition, the physical distance between two BURs in the region of interest of each BUR was measured., Results: The PDD of the proton beam from the water phantom including the BURs shows more efficient than that of conventional proton therapy on tumour region. A 719keV prompt gamma ray peak was clearly observed in the prompt gamma ray energy spectrum. The prompt gamma ray image was reconstructed successfully using 64 projections. Different image profiles including two BURs were acquired from the reconstructed image according to the iteration number., Conclusion: We confirmed successful acquisition of a prompt gamma ray image during PBFT. In addition, the quantitative image analysis results showed relatively good performance for further study., (Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Purpose: Reirradiation of head and neck (H&N) cancer is a clinical challenge. Proton radiation therapy (PRT) offers dosimetric advantages for normal tissue sparing and may benefit previously irradiated patients. Here, we report our initial experience with the use of PRT for H&N reirradiation, with focus on clinical outcomes and toxicity., Methods and Materials: We retrospectively reviewed the records of patients who received H&N reirradiation with PRT from April 2011 through June 2015. Patients reirradiated with palliative intent or without prior documentation of H&N radiation therapy were excluded. Radiation-related toxicities were recorded according to the Common Terminology Criteria for Adverse Events Version 4.0., Results: The conditions of 60 patients were evaluated, with a median follow-up time of 13.6 months. Fifteen patients (25%) received passive scatter proton therapy (PSPT), and 45 (75%) received intensity modulated proton therapy (IMPT). Thirty-five patients (58%) received upfront surgery, and 44 (73%) received concurrent chemotherapy. The 1-year rates of locoregional failure-free survival, overall survival, progression-free survival, and distant metastasis-free survival were 68.4%, 83.8%, 60.1%, and 74.9%, respectively. Eighteen patients (30%) experienced acute grade 3 (G3) toxicity, and 13 (22%) required a feeding tube at the end of PRT. The 1-year rates of late G3 toxicity and feeding tube independence were 16.7% and 2.0%, respectively. Three patients may have died of reirradiation-related effects (1 acute and 2 late)., Conclusions: Proton beam therapy can be a safe and effective curative reirradiation strategy, with acceptable rates of toxicity and durable disease control., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: In the current study, the authors sought to both characterize the national trends in proton therapy use for prostate cancer and determine the factors associated with receipt of this limited resource, using what to the best of their knowledge is the largest nationwide cancer registry., Methods: The National Cancer Data Base was used to identify 187,730 patients diagnosed with nonmetastatic prostate cancer from 2004 through 2012 who received external beam radiotherapy as their initial form of definitive therapy. Multivariable logistic regression analysis adjusted for sociodemographic and clinical factors was used to identify independent determinants of proton therapy use., Results: The rate of proton therapy use increased significantly from 2.3% in 2004 to 5.2% in 2011 and 4.8% in 2012 (P value for trend <.0001). Proton therapy for prostate cancer was much more likely to be delivered at an academic compared with nonacademic center and to patients who were white, younger, healthier, from metropolitan areas, from zip codes with higher median household incomes, and who did not have an advanced stage of or high-grade disease (all P<.0001). Compared with white patients, those who were black and Hispanic were found to be significantly less likely to receive proton therapy even after robust multivariable adjustments (adjusted odds ratio, 0.20 [95% confidence interval, 0.18-0.22; P<.0001] and adjusted odds ratio, 0.57 [95% confidence interval, 0.48-0.66; P<.0001], respectively)., Conclusions: The use of proton therapy to treat patients with prostate cancer more than doubled from 2004 to 2012, with striking racial disparities in its use noted despite robust multivariable adjustments. Long-term follow-up is needed to determine whether the increased use of proton therapy for prostate cancer is justified, and ongoing efforts should be made to ensure equal access to resource-limited oncologic therapies. Cancer 2016;122:1505-12. © 2016 American Cancer Society., (© 2016 American Cancer Society.)