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Stereotactic radiation therapy (SRT) is a proven effective treatment for brain metastases (BM); however, symptomatic radiation necrosis (RN) is a late effect that may impact on patient’s quality of life. The aim of our study was to retrospectively evaluate survival outcomes and characterize the occurrence of RN in a cohort of BM patients treated with ablative SRT at Federico II University Hospital. Clinical and dosimetric factors of 87 patients bearing a total of 220 BMs treated with SRT from 2016 to 2022 were analyzed. Among them, 46 patients with 127 BMs having clinical and MRI follow-up (FUP) ≥ 6 months were selected for RN evaluation. Dosimetric parameters of the uninvolved brain (brain without GTV) were extracted. The crude local control was 91% with neither clinical factors nor prescription dose correlating with local failure (LF). At a median FUP of 9 (1–68) months, the estimated median overall survival (OS), progression-free survival (PFS), and brain progression-free survival (bPFS) were 16, 6, and 9 months, respectively. The estimated OS rates at 1 and 3 years were 59.8% and 18.3%, respectively; bPFS at 1 and 3 years was 29.9% and 13.5%, respectively; PFS at 1 and 3 years was 15.7% and 0%, respectively; and local failure-free survival (LFFS) at 1 and 3 years was 87.2% and 83.8%, respectively. Extracranial disease status was an independent factor related to OS. Fourteen (30%) patients manifested RN. At multivariate analysis, adenocarcinoma histology, left location, and absence of chemotherapy were confirmed as independent risk factors for any-grade RN. Nine (20%) patients developed symptomatic (G2) RN, which improved or stabilized after 1–16 months of steroid therapy. With prompt recognition and, when necessary, medical therapy, RN radiological and clinical amelioration can be obtained.

Uveal melanoma (UM) represents the most common primary intraocular tumor, and nowadays eye plaque brachytherapy (EPB) is the most frequently used visual acuity preservation treatment option for small to medium sized UMs. The excellent local tumor control (LTC) rate achieved by EPB may be associated with severe complications and adverse events. Several dosimetric and clinical risk factors for the development of EPB-related ocular morbidity can be identified. However, morbidity predictive models specifically developed for EPB are still scarce. PRISMA methodology was used for the present systematic review of articles indexed in PubMed in the last sixteen years on EPB treatment of UM which aims at determining the major factors affecting local tumor control and ocular morbidities. To our knowledge, for the first time in EPB field, local tumor control probability (TCP) and normal tissue complication probability (NTCP) modelling on pooled clinical outcomes were performed. The analyzed literature (103 studies including 21,263 UM patients) pointed out that Ru-106 EPB provided high local control outcomes while minimizing radiation induced complications. The use of treatment planning systems (TPS) was the most influencing factor for EPB outcomes such as metastasis occurrence, enucleation, and disease specific survival, irrespective of radioactive implant type. TCP and NTCP parameters were successfully extracted for 5-year LTC, cataract and optic neuropathy. In future studies, more consistent recordings of ocular morbidities along with accurate estimation of doses through routine use of TPS are needed to expand and improve the robustness of toxicity risk prediction in EPB.

Purpose: To identify predictors of hypothyroidism after chemoradiation therapy for Hodgkin lymphoma (HL) and to compare outcomes after intensity modulated radiation therapy (IMRT) with those after 3-dimensional (3D) conformal radiation therapy (CRT). Methods and Materials: Ninety patients who underwent involved-site IMRT in 2009 through 2014 were evaluated for treatment-induced hypothyroidism, defined as elevated thyroid-stimulating hormone or decreased free thyroxine levels (or both). Receiver operating characteristic curve analysis identified individuals at low versus high risk based on dosimetric variables. Dosimetric cutoff points were verified with an external data set of 50 patients who underwent 3D-CRT. Results: In the IMRT group, most patients (75 [83%]) had stage II HL, and the median prescribed dose was 30.6 Gy; in the 3D-CRT group, 32 patients (64%) had stage II HL, and the median prescribed dose was 32.0 Gy. No differences were found in the proportions of patients with bilateral (P =.982) or unilateral (P =.074) neck involvement between the 2 groups. Hypothyroidism rates were marginally higher in the IMRT group, with estimated 3-year rates of freedom from hypothyroidism of 56.1% in the 3D-CRT group and 40% in the IMRT group (P =.057). Univariate analysis showed that smaller thyroid volume and higher thyroid dose were associated with hypothyroidism in both groups (P =25 Gy (V25) and the absolute volume of the thyroid gland spared from 25 Gy (VS25Gy) were the strongest predictors of hypothyroidism (P =.001 and P

The contemporary approach to the management of a cancer patient requires an "ab initio" involvement of different medical domains in order to correctly design an individual patient's pathway toward cure. With new therapeutic tools in every medical field developing faster than ever before the patient care outcomes can be achieved if all surgical, drug, and radiation options are considered in the design of the appropriate therapeutic strategy for a given patient. Radiation therapy (RT) is a clinical discipline in which experts from different fields continuously interact in order to manage the multistep process of the radiation treatment. RT is found to be an appropriate intervention for diverse indications in about 50% of cancer patients during the course of their disease. Technologies are essential in dealing with the complexity of RT treatments and for driving the increasingly sophisticated RT approaches becoming available for the treatment of Cancer. High conformal techniques, namely intensity modulated or volumetric modulated arc techniques, ablative techniques (Stereotactic Radiotherapy and Stereotactic Radiosurgery), particle therapy (proton or carbon ion therapy) allow for success in treating irregularly shaped or critically located targets and for the sharpness of the dose fall-off outside the target. The advanced on-board imaging, including real-time position management systems, makes possible image-guided radiation treatment that results in substantial margin reduction and, in select cases, implementation of an adaptive approach. The therapeutic gains of modern RT are also due in part to the enhanced anticancer activity obtained by coadministering RT with chemotherapy, targeted molecules, and currently immune checkpoints inhibitors. These main clinically relevant steps forward in Radiation Oncology represent a change of gear in the field that may have a profound impact on the management of cancer patients.

Mathematical models of normal tissue complication probability (NTCP) able to robustly predict radiation-induced morbidities (RIM) play an essential role in the identification of a personalized optimal plan, and represent the key to maximizing the benefits of technological advances in radiation therapy (RT). Most modern RT techniques pose, however, new challenges in estimating the risk of RIM. The aim of this report is to schematically review NTCP models in the framework of advanced radiation therapy techniques. Issues relevant to hypofractionated stereotactic body RT and ion beam therapy are critically reviewed. Reirradiation scenarios for new or recurrent malignances and NTCP are also illustrated. A new phenomenological approach to predict RIM is suggested.

Background: Different modern radiation therapy treatment solutions for breast cancer (BC) and regional nodal irradiation (RNI) have been proposed. In this study, we evaluate the potential reduction in radiation-induced skin morbidity obtained by intensity modulated proton therapy (IMPT) compared with intensity modulated photon therapy (IMXT) for left-side BC and RNI. Material and Methods: Using CT scans from 10 left-side BC patients, treatment plans were generated using IMXT and IMPT techniques. A dose of 50 Gy (or Gy [RBE] for IMPT) was prescribed to the target volume (involved breast, the internal mammary, supraclavicular, and infraclavicular nodes). Two single filed optimization IMPT (IMPT1 and IMPT2) plans were calculated without and with skin optimization. For each technique, skin dose-metrics were extracted and normal tissue complication probability (NTCP) models from the literature were employed to estimate the risk of radiation-induced skin morbidity. NTCPs for relevant organs-at-risk (OARs) were also considered for reference. The non-parametric Anova (Friedman matched-pairs signed-rank test) was used for comparative analyses. Results: IMPT improved target coverage and dose homogeneity even if the skin was included into optimization strategy (HIIMPT2 = 0.11 vs. HIIMXT = 0.22 and CIIMPT2 = 0.96 vs. CIIMXT = 0.82, p < .05). A significant relative skin risk reduction (RR = NTCPIMPT/NTCPIMXT) was obtained with IMPT2 including the skin in the optimization with a RR reduction ranging from 0.3 to 0.9 depending on the analyzed skin toxicity endpoint/model. Both IMPT plans attained significant OARs dose sparing compared with IMXT. As expected, the heart and lung doses were significantly reduced using IMPT. Accordingly, IMPT always provided lower NTCP values. Conclusions: IMPT guarantees optimal target coverage, OARs sparing, and simultaneously minimizes the risk of skin morbidity. The applied model-based approach supports the potential clinical relevance of IMPT for left-side BC and RNI and might be relevant for the setup of cost-effectiveness evaluation strategies based on NTCP predictions, as well as for establishing patient selection criteria.

The progressive integration of positron emission tomography/computed tomography (PET/CT) imaging in radiation therapy has its rationale in the biological intertumoral and intratumoral heterogeneity of malignant lesions that require the individual adjustment of radiation dose to obtain an effective local tumor control in cancer patients. PET/CT provides information on the biological features of tumor lesions such as metabolism, hypoxia, and proliferation that can identify radioresistant regions and be exploited to optimize treatment plans. Here, we provide an overview of the basic principles of PET-based target volume selection and definition using F-18-fluorodeoxyglucose (F-18-FDG) and then we focus on the emerging strategies of dose painting and adaptive radiotherapy using different tracers. Previous studies provided consistent evidence that integration of F-18-FDG PET/CT in radiotherapy planning improves delineation of target volumes and reduces the uncertainties and variabilities of anatomical delineation of tumor sites. PET-based dose painting and adaptive radiotherapy are feasible strategies although their clinical implementation is highly demanding and requires strong technical, computational, and logistic efforts. Further prospective clinical trials evaluating local tumor control, survival, and toxicity of these emerging strategies will promote the full integration of PET/CT in radiation oncology. (C) 2019 Elsevier Inc. All rights reserved.

Background Technological advances in Hodgkin lymphoma (HL) radiation therapy (RT) by high conformal treatments potentially increase control over organs-at-risk (OARs) dose distribution. However, plan optimization remains a time-consuming task with great operator dependent variability. Purpose of the present study was to devise a fully automated pipeline based on the Pinnacle3 Auto-Planning (AP) algorithm for treating female supradiaphragmatic HL (SHL) patients. Methods CT-scans of 10 female patients with SHL were considered. A “butterfly” (BF) volumetric modulated arc therapy was optimized using SmartArc module integrated in Pinnacle3 v. 9.10 using Collapsed Cone Convolution Superposition algorithm (30 Gy in 20 fractions). Human-driven (Manual-BF) and AP-BF optimization plans were generated. For AP, an optimization objective list of Planning Target Volume (PTV)/OAR clinical goals was first implemented, starting from a subset of 5 patients used for algorithm training. This list was then tested on the remaining 5 patients (validation set). In addition to the BF technique, the AP engine was applied to a 2 coplanar disjointed arc (AP-ARC) technique using the same objective list. For plan evaluation, dose-volume-histograms of PTVs and OARs were extracted; homogeneity and conformity indices (HI and CI), OARs dose-volume metrics and odds for different toxicity endpoints were computed. Non-parametric Friedman and Dunn tests were used to identify significant differences between groups. Results A single AP objective list for SHL was obtained. Compared to the manual plan, both AP-plans offer comparable CIs while AP-ARC also achieved comparable HIs. All plans fulfilled the clinical dose criteria set for OARs: both AP solutions performed at least as good as Manual-BF plan. In particular, AP-ARC outperformed AP-BF in terms of heart sparing involving a lower risk of coronary events and radiation-induced lung fibrosis. Hands-on planning time decreased by a factor of 10 using AP on average. Conclusions Despite the high interpatient PTV (size and position) variability, it was possible to set a standard SHL AP optimization list with a high level of generalizability. Using the implemented list, the AP module was able to limit OAR doses, producing clinically acceptable plans with stable quality without additional user input. Overall, the AP engine associated to the arc technique represents the best option for SHL.

Purpose Delta4 Discover (ScandiDos, Uppsala, Sweden) is a new device developed in order to monitor online complex radiation techniques such as volumetric-modulated arc therapy (VMAT). It can be inserted between the radiation source and the patient so it can potentially impact the beam quality that the patient receives. The aim of this work is to investigate, in terms of beam’s attenuation, the feasibility of using Discover transmission array [1] . Methods 9 VMAT treatment plans, generated using Pinnacle3’s SmartArc algorithm v.9.10 (Philips Fitchburg, USA), for various treatment sites, were delivered using Delta4 Phantom+ (ScandiDos, Uppsala, Sweden). The response, with and without the Discover mounted on the linac was evaluated. All plans were delivered on a Varian TrueBeam STx equipped with HD MLC. For phantom verification, plans were recalculated replacing the patient planning CT scan with a phantom CT scan. Dose distributions of each plan delivered with and without Discover were verified using the Delta4 Phantom + and compared to calculated dose. Results Analyzing dose difference profiles, the Relative Dose Difference, between the measured dose relative to both configurations, showed that the absorption of beam radiation observed was on average about 1%. About Median Dose Deviation between the calculated and measured dose for both configurations we found that the all Median Dose Deviation shift values are ranging from 0.2% to 1.3%. Conclusions The thin transmission detector Delta4 Discover shows good potential for real time quality assurance. The minimal attenuation observed potentially allows for a real time verification and independent monitoring of complex VMAT deliveries during patient treatment.

Francesco Perri,1 Salvatore Pisconti,1 Manuel Conson,2,3 Roberto Pacelli,2,3 Giuseppina Della Vittoria Scarpati,2 Antonio Gnoni,1 Carmine D’Aniello,1 Carla Cavaliere,1 Antonella Licchetta,1 Laura Cella,2,3 Mario Giuliano,4,5 Concetta Schiavone,7 Sara Falivene,7 Giuseppe Di Lorenzo,4 Carlo Buonerba,6 Vincenzo Ravo,7 Paolo Muto7 1Medical Oncology Unit, POC S Annunziata, Taranto, 2Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, 3Institute of Biostructures and Bioimaging, National Council of Research, Naples, 4Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy; 5Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA; 6Division of Oncology, Centro di riferimento Oncologico di Basilicata, IRCCS Rionero in Vulture, Potenza, 7Department of Radiotherapy, Istituto Nazionale per la Cura dei Tumori-Fondazione G. Pascale. IRCCS di Napoli, Naples, Italy Background: The clinical benefits of postoperative radiation therapy (PORT) for patients with thymoma are still controversial. In the absence of defined guidelines, prognostic factors such as stage, status of surgical margins, and histology are often considered to guide the choice of adjuvant treatment (radiotherapy and/or chemotherapy). In this study, we describe our single-institution experience of three-dimensional conformal PORT administered as adjuvant treatment to patients with thymoma. Methods: Twenty-two consecutive thymoma patients (eleven male and eleven female) with a median age of 52 years and treated at our institution by PORT were analyzed. The patients were considered at high risk of recurrence, having at least one of the following features: stage IIB or III, involved resection margins, or thymic carcinoma histology. Three-dimensional conformal PORT with a median total dose on clinical target volume of 50 (range 44–60) Gy was delivered to the tumor bed by 6–20 MV X-ray of the linear accelerator. Follow-up after radiotherapy was done by computed tomography scan every 6 months for 2 years and yearly thereafter.Results: Two of the 22 patients developed local recurrence and four developed distant metastases. Median overall survival was 100 months, and the 3-year and 5-year survival rates were 83% and 74%, respectively. Median disease-free survival was 90 months, and the 5-year recurrence rate was 32%. On univariate analysis, pathologic stage III and presence of positive surgical margins had a significant impact on patient prognosis. Radiation toxicity was mild in most patients and no severe toxicity was registered. Conclusion: Adjuvant radiotherapy achieved good local control and showed an acceptable toxicity profile in patients with high-risk thymoma. Keywords: thymoma, adjuvant treatment, three-dimensional conformal radiotherapy, local control, toxicity&nbsp

Proton beam therapy represents a promising modality for left-side breast cancer (BC) treatment, but concerns have been raised about skin toxicity and poor cosmesis. The aim of this study is to apply skin normal tissue complication probability (NTCP) model for intensity modulated proton therapy (IMPT) optimization in left-side BC.Ten left-side BC patients undergoing photon irradiation after breast-conserving surgery were randomly selected from our clinical database. Intensity modulated photon (IMRT) and IMPT plans were calculated with iso-tumor-coverage criteria and according to RTOG 1005 guidelines. Proton plans were computed with and without skin optimization. Published NTCP models were employed to estimate the risk of different toxicity endpoints for skin, lung, heart and its substructures.Acute skin NTCP evaluation suggests a lower toxicity level with IMPT compared to IMRT when the skin is included in proton optimization strategy (0.1% versus 1.7%, p 0.001). Dosimetric results show that, with the same level of tumor coverage, IMPT attains significant heart and lung dose sparing compared with IMRT. By NTCP model-based analysis, an overall reduction in the cardiopulmonary toxicity risk prediction can be observed for all IMPT compared to IMRT plans: the relative risk reduction from protons varies between 0.1 and 0.7 depending on the considered toxicity endpoint.Our analysis suggests that IMPT might be safely applied without increasing the risk of severe acute radiation induced skin toxicity. The quantitative risk estimates also support the potential clinical benefits of IMPT for left-side BC irradiation due to lower risk of cardiac and pulmonary morbidity. The applied approach might be relevant on the long term for the setup of cost-effectiveness evaluation strategies based on NTCP predictions.

Sinonasal carcinomas (SNcs) are rare neoplasms arising from the paranasal sinuses and nasal cavity. Although these tumours have a heterogeneous histology, they are commonly diagnosed as a locally advanced disease and are associated with a poor prognosis. The present retrospective study reviewed 30 patients with locally advanced SNc, who were treated with surgery followed by chemoradiotherapy or radiotherapy, or radiotherapy with or without concomitant chemotherapy between January 1999 and January 2013 at the Department of Radiation Therapy, University of Naples 'Federico II' (Naples, Italy). A total of 19 patients were treated with upfront surgery followed by adjuvant radio- or chemoradiotherapy (group A), while the remaining 11 patients received exclusive radiotherapy with or without concomitant chemotherapy (group B). Concurrent cisplatin-based chemotherapy (100 mg/m2, days 1, 22 and 43 for 3 cycles) was administered to 34% of patients in group A and 55% of patients in group B. At a median follow-up of 31 months, 33.3% of patients were alive. Cause-specific survival (CSS) and progression-free survival (PFS) times were 32 and 12 months, respectively. No difference in CSS rate was observed between the two treatment groups. Univariate analysis determined that disease stage was the only factor that significantly affected CSS (P=0.002) and PFS (P=0.0001) rates. Acute and chronic toxicities were mild, with only 23.3% of patients reporting G1-2 side effects and no treatment-related blindness. The present study reported moderate activity and efficacy of surgery followed by adjuvant radio- or chemoradiotherapy, and exclusive radiotherapy with or without chemotherapy in this poor prognosis category of patients.

Aims To identify predictors of asymptomatic radiation-induced abdominal atherosclerosis in patients treated with radiotherapy and evaluated by abdominal vascular ultrasonography. Materials and methods Forty-two testicular classic seminoma patients (median age 34 years, range 16–56) undergoing radical inguinal orchiectomy were analysed. Twenty-six patients underwent post-surgery radiotherapy (median total dose 25 Gy, range 25–43), two of them also received chemotherapy (CHT) and 16 patients were treated with surgery alone or by surgery followed by CHT (control group). The presence of stenosis in an abdominal vessel and renal resistive index (RRI), evaluated by echo-colour Doppler (ECD), were considered as indicators of late vascular damage. Chi-square and Mann-Whitney tests were used to compare groups. For the radiotherapy group, near maximum ( D 2% ) and mean dose ( D mean ) metrics of critical structures (abdominal arteries and renal hila) were extracted from retrievable dose maps (18 of 26 radiotherapy patients). To evaluate clinical and dosimetric factors associated with vascular damage, univariate and multivariate analyses were carried out. The impact of dose to arteries, evaluated as separate subvolumes, was analysed comparing the stenotic arteries with normal ones by logistic regression. The area under the receiver operator characteristic curve (AUC) was used to evaluate the test accuracy. Results In the radiotherapy group there was a significantly different incidence of stenosis (31% versus 0%, P = 0.016) and a higher median average RRI (0.63 versus 0.60, P = 0.032) compared with the control group. The median time intervals between treatment and ECD were 64 months (range 12–120) and 48 months (range 12–168) in the radiotherapy and control groups ( P = 0.399), respectively. A younger age at radiotherapy was the only clinical risk factor for stenosis ( P = 0.006). Artery D mean was significantly associated with stenosis ( P = 0.008), with an odds ratio of 1.13 (95% confidence interval 1.01–1.26) and an AUC of 0.85 (95% confidence interval 0.77–0.91). Renal hilum D 2% was correlated with RRI (Rs = 0.406, P = 0.02). Conclusions Late vascular damage represents a potential effect of abdominal radiotherapy, even at a moderate dose. Younger age at irradiation, artery and renal hila dose metrics are associated with increased risk. Ultrasound-based follow-up may allow for non-invasive early detection of asymptomatic radiation-induced damage, helping to prevent severe vascular events.

Purpose To implement and evaluate a magnetic resonance imaging atlas-based automated segmentation (MRI-ABAS) procedure for cortical and sub-cortical grey matter areas definition, suitable for dose-distribution analyses in brain tumor patients undergoing radiotherapy (RT). Patients and methods 3T-MRI scans performed before RT in ten brain tumor patients were used. The MRI-ABAS procedure consists of grey matter classification and atlas-based regions of interest definition. The Simultaneous Truth and Performance Level Estimation (STAPLE) algorithm was applied to structures manually delineated by four experts to generate the standard reference. Performance was assessed comparing multiple geometrical metrics (including Dice Similarity Coefficient – DSC). Dosimetric parameters from dose–volume-histograms were also generated and compared. Results Compared with manual delineation, MRI-ABAS showed excellent reproducibility [median DSC ABAS =1 (95% CI, 0.97–1.0) vs. DSC MANUAL =0.90 (0.73–0.98)], acceptable accuracy [DSC ABAS =0.81 (0.68–0.94) vs. DSC MANUAL =0.90 (0.76–0.98)], and an overall 90% reduction in delineation time. Dosimetric parameters obtained using MRI-ABAS were comparable with those obtained by manual contouring. Conclusions The speed, reproducibility, and robustness of the process make MRI-ABAS a valuable tool for investigating radiation dose–volume effects in non-target brain structures providing additional standardized data without additional time-consuming procedures.

Oral cavity mucosal melanomas (OCMM) represent only 3% of all malignant melanomas. Surgery is the mainstay of treatments and it is often followed by adjuvant radiotherapy. The role of adjuvant immunotherapy and/or chemotherapy is still debated and to date neither treatment is routinely used. From January 1990 to January 2010, we have collected from our database data of 20 patients with a histologically proven diagnosis of OCMM. Upfront surgery, followed by adjuvant radiotherapy was performed in 16/20 (80%) patients. Immunohistochemical analysis was carried out on all tissue samples and the following markers were assessed: Ki-67, HMG-45, Melan-A, S-100, CD31, CD35, CD20, CD21, and CD3. Although Ki-67, HMG-45, Melan-A, and S-100 were assessed in tumor cells, the analysis of CD31, CD21, CD20, CD3, and CD35 was carried out on the tumor-infiltrating lymphocytes. Patient outcome was analyzed and associated with clinical and Immunohistochemical tumor characteristics. The median overall survival (OS) was 12 months, with a 2-year OS rate of 30%. The median progression-free survival (PFS) was 9 months, with a 2-year PFS rate of 25%. Grade of lymphocyte infiltration (CD20 and CD3 expression) correlated strongly with prognosis. Interestingly, overexpression of CD21 along with downregulation of CD31 was significantly associated with better OS and PFS, whereas the reversal features correlated with a poor prognosis. Our report shows that patients affected by OCMM have a poor prognosis despite the administration of multimodal treatments. Moreover, our analysis suggests that the evaluation of several biomarkers, especially in tumor-infiltrating lymphocytes, may identify categories of patients with distinct immune response against the tumor and possibly different treatment response and prognosis.

Purpose Purpose of the present study was to report on the evaluation of Pinnacle3Auto-Planning (AP) algorithm for Hodgkin lymphoma (HL) radiation therapy (RT). Methods Planning CT-scans of 10 female patients with supradiaphragmatic HL were considered. Involved site clinical target volume (CTV) included the upper mediastinal and supraclavear nodes. Planning Target Volume (PTV) was obtained by CTV uniform 10-mm expansion. A total dose of 30 Gy was prescribed in 20 fractions. A “butterfly” (BF) volumetric modulated arc therapy was planned with Pinnacle3 v. 9.10 using SmartArc module and Collapsed Cone Convolution Superposition algorithm dose calculation. Human-driven (Manual-BF) and AP-BF optimization plans were generated using published priority and constraints on the OARs. In addition to BF technique, the AP engine was applied to a 2 coplanar disjointed arches (AP-ARC) technique. A single AP optimization list of PTV/OAR clinical goals was created for each patient. For plan comparison, DVHs of PTVs and OARs were extracted; homogeneity and conformity indices (HI and CI) computed and OARs dose-volume constraints and NTCP models for RP, HT, and CD evaluated. Non-parametric Friedman and Dunn tests were used to identify significant differences between groups. Results AP (AP-BF or AP-ARC) offers comparable coverage of the PTV as the manual plan and a consistently better sparing of OARs. In particular, the heart and thyroid mean doses and lung V20 were significantly reduced using AP engine. Accordingly, AP provides similar, if not lower, complication risks. The median number of monitor units was slightly reduced by AP (3.5%). Hands-on planning time decreased on average by a factor of 3 by AP. Conclusions The AP module was able to limit heart and thyroid complication risks, producing clinically acceptable HL plans with stable quality without additional user input. Overall AP-ARC provided better results in terms of OAR sparing when compared with AP-BF.

Purpose The aim of this work was to investigate the feasibility of using a new positioning system (Manufacturer TOTIM – Totally Immobile) for patients’ set-up. Methods The device consists of a sealed cushion with external cover in microfiber polyester containing a bag filled with two separate reagents mixed by hands during usage. These reagents develop an exothermic reaction producing polyurethane foam, which can be modelled around the patient’s body. The beam’s attenuation was investigated using a Varian TrueBeam STx linear accelerator, equipped with 120HD MLC for different photon beams energies. We tested two different cushions: the TOTIM T30002 Jolly and the TOTIM T30006 Limb model. The measurements were performed using a water equivalent phantom, with a IBA Dosimetry Farmer ionization chamber Type FC65-P positioned at isocenter, SSD = 95 cm and gantry angle at 180 degrees, the field size was defined at 10 × 10 cm2. Measurements were performed also with the Delta4 Phantom+ (ScandiDos, Uppsala, Sweden) in two different set-ups: with and without TOTIM T30006 Limb cushion to evaluate the attenuation in a quality assurance (QA) specific patient. The temperature values during the exothermic process at 60 s intervals were monitored too. Results During the exothermic reaction, an observed maximum of temperature (around 50° at 300 s) comes before the solidification process, after that the temperature starts to decrease asymptotically (Fig. 1). The attenuation factor for both cushions was about 1%. The median dose deviation between measured and calculated dose using Delta4 Phantom+ was about 1.3%. Conclusion The easy use and the stability of solidification, the low absorption value make TOTIM devices an useful system of patient’s immobilization.

A neoadjuvant clinical trial was previously conducted in patients with resectable colorectal cancer liver metastases (CRLM). At a median follow up of 28 months, 20/33 patients were dead of disease, 8 were alive with disease and 5 were alive with no evidence of disease. To shed further insight into biological features accounting for different outcomes, the expression of CXCR4-CXCL12-CXCR7, TLR2-TLR4, and the programmed death receptor-1 (PD-1)/programmed death-1 ligand (PD-L1) was evaluated in excised liver metastases. Expression profiles were assessed through qPCR in metastatic and unaffected liver tissue of 33 CRLM neoadjuvant-treated patients. CXCR4 and CXCR7, TLR2/TLR4, and PD-1/PD-L1 mRNA were significantly overexpressed in metastatic compared to unaffected liver tissues. CXCR4 protein was negative/low in 10/31, and high in 21/31, CXCR7 was negative/low in 16/31 and high in 15/31, CXCL12 was negative/low in 14/31 and high in 17/31 CRLM. PD-1 was negative in 19/30 and positive in 11/30, PD-L1 was negative/low in 24/30 and high in 6/30 CRLM. Stromal PD-L1 expression, affected the progression-free survival (PFS) in the CRLM population. Patients overexpressing CXCR4 experienced a worse PFS and cancer specific survival (CSS) (p = 0.001 and p = 0.0008); in these patients, KRAS mutation identified a subgroup with a significantly worse CSS (p < 0.01). Thus, CXCR4 and PD-L1 expression discriminate patients with the worse PFS within the CRLM evaluated patients. Within the CXCR4 high expressing patients carrying Mut-KRAS in CRLM identifies the worst prognostic group. Thus, CXCR4 targeting plus anti-PD-1 therapy should be explored to improve the prognosis of Mut-KRAS-high CXCR4-CRLMs.

To apply a voxel-based (VB) approach aimed at exploring local dose differences associated with late radiation-induced lung damage (RILD).An interinstitutional database of 98 patients who were Hodgkin lymphoma (HL) survivors treated with postchemotherapy supradiaphragmatic radiation therapy was analyzed in the study. Eighteen patients experienced late RILD, classified according to the Radiation Therapy Oncology Group scoring system. Each patient's computed tomographic (CT) scan was normalized to a single reference case anatomy (common coordinate system, CCS) through a log-diffeomorphic approach. The obtained deformation fields were used to map the dose of each patient into the CCS. The coregistration robustness and the dose mapping accuracy were evaluated by geometric and dose scores. Two different statistical mapping schemes for nonparametric multiple permutation inference on dose maps were applied, and the corresponding P.05 significance lung subregions were generated. A receiver operating characteristic (ROC)-based test was performed on the mean dose extracted from each subregion.The coregistration process resulted in a geometrically robust and accurate dose warping. A significantly higher dose was consistently delivered to RILD patients in voxel clusters near the peripheral medial-basal portion of the lungs. The area under the ROC curves (AUC) from the mean dose of the voxel clusters was higher than the corresponding AUC derived from the total lung mean dose.We implemented a framework including a robust registration process and a VB approach accounting for the multiple comparison problem in dose-response modeling, and applied it to a cohort of HL survivors to explore a local dose-RILD relationship in the lungs. Patients with RILD received a significantly greater dose in parenchymal regions where low doses (∼6 Gy) were delivered. Interestingly, the relation between differences in the high-dose range and RILD seems to lack a clear spatial signature.

The purpose of this study was to evaluate the outcome prediction power of classical prognostic factors along with surrogate approximation of genetic signatures (AGS) subtypes in patients affected by localized breast cancer (BC) and treated with postoperative radiotherapy. We retrospectively analyzed 468 consecutive female patients affected by localized BC with complete immunohistochemical and pathological information available. All patients underwent surgery plus radiotherapy. Median follow-up was 59 months (range, 6-132) from the diagnosis. Disease recurrences (DR), local and/or distant, and contralateral breast cancer (CBC) were registered and analyzed in relation to subtypes (luminal A, luminal B, HER-2, and basal), and classical prognostic factors (PFs), namely age, nodal status (N), tumor classification (T), grading (G), estrogen receptors (ER), progesterone receptors and erb-B2 status. Bootstrap technique for variable selection and bootstrap resampling to test selection stability were used. Regarding AGS subtypes, HER-2 and basal were more likely to recur than luminal A and B subtypes, while patients in the basal group were more likely to have CBC. However, considering PFs along with AGS subtypes, the optimal multivariable predictive model for DR consisted of age, T, N, G and ER. A single-variable model including basal subtype resulted again as the optimal predictive model for CBC. In patients bearing localized BC the combination of classical clinical variables age, T, N, G and ER was still confirmed to be the best predictor of DR, while the basal subtype was demonstrated to be significantly and exclusively correlated with CBC.

Hypothyroidism (HT) is a frequent late side effect of Hodgkin's lymphoma (HL) therapy. The purpose of this study is to determine dose-volume constraints that correlate with functional impairment of the thyroid gland in HL patients treated with three-dimensional radiotherapy.A total of 61 consecutive patients undergoing antiblastic chemotherapy and involved field radiation treatment (median dose, 32 Gy; range, 30-36 Gy) for HL were retrospectively considered. Their median age was 28 years (range, 14-70 years). Blood levels of thyroid-stimulating hormone (TSH), free triiodo-thyronine (FT3), free thyroxine (FT4), and thyroglobulin antibody (ATG) were recorded basally and at different times after the end of therapy. For the thyroid gland, normal tissue complication probability (NTCP), dosimetric parameters, and the percentage of thyroid volume exceeding 10, 20, and 30 Gy (V10, V20, and V30) were calculated in all patients. To evaluate clinical and dosimetric factors possibly associated with HT, univariate and multivariate logistic regression analyses were performed.Eight of 61 (13.1%) patients had HT before treatment and were excluded from further evaluation. At a median follow-up of 32 months (range, 6-99 months), 41.5% (22/53) of patients developed HT after treatment. Univariate analyses showed that all dosimetric factors were associated with HT (p0.05). On multivariate analysis, the thyroid V30 value was the single independent predictor associated with HT (p = 0.001). This parameter divided the patients into low- vs. high-risk groups: if V30 was ≤ 62.5%, the risk of developing HT was 11.5%, and if V30 was62.5%, the risk was 70.8% (p0.0001). A Cox regression curve stratified by two levels of V30 value was created (odds ratio, 12.6).The thyroid V30 predicts the risk of developing HT after sequential chemo-radiotherapy and defines a useful constraint to consider for more accurate HL treatment planning.

BACKGROUND: Severe acute radiation-induced skin toxicity (RIST) after breast irradiation is a side effect impacting the quality of life in breast cancer (BC) patients. The aim of the present study was to develop normal tissue complication probability (NTCP) models of severe acute RIST in BC patients. PATIENTS AND METHODS: We evaluated 140 consecutive BC patients undergoing conventional three-dimensional conformal radiotherapy (3D-CRT) after breast conserving surgery in a prospective study assessing acute RIST. The acute RIST was classified according to the RTOG scoring system. Dose-surface histograms (DSHs) of the body structure in the breast region were extracted as representative of skin irradiation. Patient, disease, and treatment-related characteristics were analyzed along with DSHs. NTCP modeling by Lyman-Kutcher-Burman (LKB) and by multivariate logistic regression using bootstrap resampling techniques was performed. Models were evaluated by Spearman's Rs coefficient and ROC area. RESULTS: By the end of radiotherapy, 139 (99%) patients developed any degree of acute RIST. G3 RIST was found in 11 of 140 (8%) patients. Mild-moderate (G1-G2) RIST was still present at 40 days after treatment in six (4%) patients. Using DSHs for LKB modeling of acute RIST severity (RTOG G3 vs. G0-2), parameter estimates were TD50=39 Gy, n=0.38 and m=0.14 [Rs = 0.25, area under the curve (AUC) = 0.77, p = 0.003]. On multivariate analysis, the most predictive model of acute RIST severity was a two-variable model including the skin receiving ≥30 Gy (S30) and psoriasis [Rs = 0.32, AUC = 0.84, p

Gastrointestinal (GI) toxicity is a common effect following radiation therapy (RT) for prostate cancer. Purpose of the present work is to compare two Normal Tissue Complication Probability (NTCP) modelling approaches for prediction of late radio-induced GI toxicity after prostate external beam radiotherapy. The study includes 84 prostate cancer patients evaluated for late rectal toxicity after 3D conformal radiotherapy. Median age was 72 years (range 53-85). All patients received a total dose of 76 Gy to the prostate gland with daily fractions of 2 Gy. The acute and late radio-induced GI complications were classified according to the RTOG/EORTC scoring system. Rectum dose-volume histograms were extracted for Lyman-Kutcher-Burman (LKB) NTCP model fitting using Maximum Likelihood Estimation. The bootstrap method was employed to test the fit robustness. The area under the receiver operating characteristic curve (AUC) was used to evaluate the predictive power of the LKB and to compare it with a multivariate logistic NTCP model previously determined. At a median follow-up of 36 months, 42% (35/84) of patients experienced grade 1-2 (G1-2) acute GI events while 25% (21/84) of patients developed G1-2 late GI events. The best-estimate of fitting parameters for LKB NTCP model for mild\moderate GI toxicity resulted to be: D 50 = 87.3 Gy, m = 0.37 and n = 0.10. Bootstrap result showed that the parameter fit was robust. The AUC values for the LKB and for the multivariate logistic models were 0.60 and 0.75, respectively. We derived the parameters of the LKB model for mild\moderate GI toxicity prediction and we compared its performance with that of a data-driven multivariate model. Compared to LKB, the multivariate model confirmed a higher predictive power as showed by the AUC values.

Purpose. To develop a predictive multivariate normal tissue complication probability (NTCP) model for radiation-induced heart valvular damage (RVD). The influence of combined heart-lung irradiation on RVD development was included.Material and methods. Multivariate logistic regression modeling with the least absolute shrinkage and selection operator (LASSO) was used to build an NTCP model to predict RVD based on a cohort of 90 Hodgkin lymphoma patients treated with sequential chemo-radiation therapy. In addition to heart irradiation factors, clinical variables, along with left and right lung dose-volume histogram statistics, were included in the analysis. To avoid overfitting, 10-fold cross-validation (CV) was used for LASSO logistic regression modeling, with 50 reshuffled cycles. Model performance was assessed using the area under the receiver operating characteristic (ROC) curve (AUC) and Spearman's correlation coefficient (Rs).Results. At a median follow-up time of 55 months (range 12–92 months) after the end of radiation treatment, 27 of 90 patients (30%) manifested at least one kind of RVD (mild or moderate), with a higher incidence of left-sided valve defects (64%). Fourteen prognostic factors were frequently selected (more than 100/500 model fits) by LASSO, which included mainly heart and left lung dosimetric variables along with their volume variables. The averaged cross-validated performance was AUC-CV = 0.685 and Rs = 0.293. The overall performance of a final NTCP model for RVD obtained applying LASSO logistic regression to the full dataset was satisfactory (AUC = 0.84, Rs = 0.55, p < 0.001).Conclusion. LASSO proved to be an improved and flexible modeling method for variable selection. Applying LASSO, we showed, for the first time, the importance of jointly considering left lung irradiation and left lung volume size in the prediction of subclinical radiation-related heart disease resulting in RVD.