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Introduction: Partial breast irradiation (PBI) has increased in utilization, with the postoperative lumpectomy cavity and clips used to guide target volumes. The ideal timing to perform computed tomography (CT)-based treatment planning for this technique is unclear. Prior studies have examined change in volume over time from surgery but not the effect of patient characteristics on lumpectomy cavity volume. We sought to investigate patient and clinical factors that may contribute to larger postsurgical lumpectomy cavities and therefore predict for larger PBI volumes. Methods: A total of 351 consecutive women with invasive or in situ breast cancer underwent planning CT after breast-conserving surgery at a single institution during 2019 and 2020. Lumpectomy cavities were contoured, and volume was retrospectively computed using the treatment planning system. Univariate and multivariate analyses were performed to evaluate the associations between lumpectomy cavity volume and patient and clinical factors. Results: Median age was 61.0 years (range, 30-91), 23.9% of patients were Black people, 52.1% had hypertension, the median body mass index (BMI) was 30.4 kg/m², 11.4% received neoadjuvant chemotherapy, 32.5% were treated prone, mean interval from surgery to CT simulation was 54.1 days ± 45.9, and mean lumpectomy cavity volume was 42.2 cm3 ± 52.0. Longer interval from surgery was significantly associated with smaller lumpectomy cavity volume on univariate analysis, p = 0.048. Race, hypertension, BMI, the receipt of neoadjuvant chemotherapy, and prone position remained significant on multivariate analysis (p < 0.05 for all). Prone position vs. supine, higher BMI, the receipt of neoadjuvant chemotherapy, the presence of hypertension, and race (Black people vs. White people) were associated with larger mean lumpectomy cavity volume. Discussion: These data may be used to select patients for which longer time to simulation may result in smaller lumpectomy cavity volumes and therefore smaller PBI target volumes. Racial disparity in cavity size is not explained by known confounders and may reflect unmeasured systemic determinants of health. Larger datasets and prospective evaluation would be ideal to confirm these hypotheses. [ABSTRACT FROM AUTHOR]

PURPOSE The landscape of the profession of academic radiation oncology is constantly changing. We sought to determine the demographic makeup of the current academic radiation oncology workforce. MATERIALS AND METHODS Internet web site searches of the 51 National Cancer Institute-designated Comprehensive Cancer Centers (CCCs) were conducted in September 2019. The Scopus database was subsequently searched in December 2019 to ascertain the h-index for each radiation oncologist. Geographic location was economically stratified (New York, California, Massachusetts, Illinois, and Washington DC) as previously reported. Race and binary sex were attributed by authors using publicly available information. Univariate analysis involved the chi-square test; a multivariable model considered several factors including rank and sex. RESULTS Of 993 radiation oncologists at CCCs, 53.6% are junior faculty, 24.8% associate professors, and 21.7% full professors. The average radiation oncologist at a CCC has been a physician for 19.7 (standard deviation 5 11.3) years; 4.7% (47/993) are under-represented minorities. 24.6% of men and 15.5% of women were full professors, a statistically significant difference (P 5 .001). Of the 51 department chairs, 11.8% are women and 5.6% are under-represented minorities. There are fewer female than male program directors in the most economically stratified locations (P 5 .02). The mean h-index for all faculty is 17.6 (standard deviation 5 16.9), and significantly differs between junior faculty (8.21), associate professors (18.46), and full professors (40.05; P, .0001). It also differs between men (19.35) and women (14.11). On multivariable analysis, sex, academic rank, and a secondary advanced degree were independently significant correlates of h-index. CONCLUSION Among academic radiation oncologists at CCCs, under 5% are under-represented minorities, men are significantly over-represented among senior faculty, and women have significantly lower h-indices than men. [ABSTRACT FROM AUTHOR]

Pre-residency peer-reviewed publications (PRP) have been associated with subsequent resident choice of academic versus private practice career. The evolution of PRP prevalence among radiation oncology resident classes has yet to be examined. A list of radiation oncology residents from the graduating classes of 2016 and 2022 were obtained, and PRP was compiled as the number of publications a resident had listed in PubMed as of the end of the calendar year of residency application. Statistical analysis was conducted using Fisher's exact test. Analysis of 163 residents from the 2016 class compared with 195 from the 2022 class revealed that the proportion of residents with zero PRP decreased from 46.6% to 23.6% between the 2016 to 2022 classes (p<0.0001), while that of residents with one PRP increased from 17.8% to 19.0% (p>0.05) and with at least two PRP increased from 35.6% to 57.4% (p<0.0001). Residents with a PhD were more likely to have at least two PRP in each class (p<0.0001). As with the class of 2016, there remained no significant difference in PRP by gender for the class of 2022. Over the past six years, PRP has become more prevalent among incoming radiation oncology residents. Residents in the class of 2016 were 180% less likely than the class of 2022 to have at least one PRP, and 60% less likely to have at least two PRP. These findings are indicative of the increasing pressure on medical students to enter residency with a publication background. [ABSTRACT FROM AUTHOR]

Aim: To identify demographic predictors of patients who miss oncology follow-up, considering that missed follow-up has not been well studies in cancer patients. Methods: Patients with solid tumors diagnosed from 2007 to 2016 were analyzed (n = 16,080). Univariate and multivariable logistic regression models were constructed to examine predictors of missed follow-up. Results: Our study revealed that 21.2% of patients missed ≥1 follow-up appointment. African-American race (odds ratio [OR] 1.33; 95% CI: 1.17-1.51), Medicaid insurance (OR 1.59; 1.36-1.87), no insurance (OR 1.66; 1.32-2.10) and rural residence (OR 1.78; 1.49-2.13) were associated with missed follow-up. Conclusion: Many cancer patients miss follow-up, and inadequate follow-up may influence cancer outcomes. Further research is needed on how to address disparities in follow-up care in high-risk patients. [ABSTRACT FROM AUTHOR]

Background: We used two models to simulate a proposed noninferiority trial of radiotherapy (RT) omission in low-risk invasive breast cancer to illustrate how modeling could be used to predict the trial's outcomes, inform trial design, and contribute to practice debates.Methods: The proposed trial was a prospective randomized trial of no-RT vs RT in women age 40 to 74 years undergoing lumpectomy and endocrine therapy for hormone receptor-positive, human epidermal growth factor receptor 2-negative, stage I breast cancer with an Oncotype DX score of 18 or lower. The primary endpoint was recurrence-free interval (RFI), including locoregional recurrence, distant recurrence, and breast cancer death. Noninferiority required the two-sided 90% confidence interval of the RFI hazard ratio (HR) for no-RT vs RT to be entirely below 1.7. Model inputs included published data. The trial was simulated 1000 times, and results were summarized as percent concluding noninferiority and mean (standard deviation) of hazard ratios for Model GE and Model M, respectively.Results: Noninferiority was demonstrated in 18.0% and 3.7% for the two models. The respective means (SD) of the RFI hazard ratios were 1.8 (0.7) and 2.4 (0.9); most were locoregional recurrences. The mean five-year RFI rates for no-RT vs RT (SD) were 92.7% (2.9%) vs 95.5% (2.2%) and 88.4% (2.0%) vs 94.5% (1.6%). Both models showed little or no difference in breast cancer-specific or overall survival. Alternative definitions of low risk based on combinations of age and grade produced similar results.Conclusions: The proposed trial was unlikely to show noninferiority of omitting radiotherapy even using alternative definitions of low-risk, as the endpoint included local recurrence. Future trials regarding radiotherapy should address absolute reduction in recurrence and impact of type of recurrence on the patient. [ABSTRACT FROM AUTHOR]

Background: Radiotherapy after breast conservation has become the standard of care. Prior meta-analyses on effects of radiotherapy predated availability of gene expression profiling (GEP) to assess recurrence risk and/or did not include all relevant outcomes. This analysis used GEP information with pooled individual-level data to evaluate the impact of omitting radiotherapy on recurrence and mortality.Methods: We considered trials that evaluated or administered radiotherapy after lumpectomy in women with low-risk breast cancer. Women included had undergone lumpectomy and were treated with hormonal therapy for stage I, ER+ and/or PR+, HER2- breast cancer with Oncotype scores no greater than 18. Recurrence-free interval (RFI), type of RFI (locoregional or distant), and breast cancer-specific and overall survival were compared between no radiotherapy and radiotherapy using adjusted Cox models. All statistical tests were two-sided.Results: The final sample included 1778 women from seven trials. Omission of radiotherapy was associated with an overall adjusted hazard ratio of 2.59 (95% confidence interval [CI] = 1.38 to 4.89, P = .003) for RFI. There was a statistically significant increase in any first locoregional recurrence (P = .001), but not distant recurrence events (P = .90), or breast cancer-specific (P = .85) or overall survival (P = .61). Five-year RFI rate was high (93.5% for no radiotherapy vs 97.9% for radiotherapy; absolute reduction = 4.4%, 95% CI = 0.7% to 8.1%, P = .03). The effects of radiotherapy varied across subgroups, with lower RFI rates for those with Oncotype scores of less than 11 (vs 11-18), older (vs younger), and ER+/PR+ status (vs other).Conclusions: Omission of radiotherapy in hormone-sensitive patients with low recurrence risk may lead to a modest increase in locoregional recurrence event rates, but does not appear to increase the rate of distant recurrence or death. [ABSTRACT FROM AUTHOR]

The management of early-stage breast cancer in older patients is complex and requires a careful balance of the risk of cancer death with the competing risks of comorbidities and treatment-related toxicity in women with largely favorable disease. As the US population continues to age, oncologists will increasingly encounter this clinical challenge. Several strategies involving each core component of breast cancer therapy have been investigated to minimize treatment in these patients while still maintaining acceptable outcomes. These include omission of primary tumor resection, surgical axillary evaluation, systemic chemotherapy, and/or radiotherapy, as well as reduction in radiotherapy treatment volume (partial breast irradiation) or total treatment time (hypofractionation). We review these strategies and the literature supporting their use, as well as future directions for treatment minimization. [ABSTRACT FROM AUTHOR]

High-dose-rate intraoperative radiation therapy (HDR-IORT) has historically provided effective local control (LC) for patients with unresectable and recurrent tumors. However, IORT is limited to only a few specialized institutions and it can be difficult to initiate an HDR-IORT program. Herein, we provide a brief overview on how to initiate and implement an HDR-IORT program for a selected group of patients with gastrointestinal and pelvic solid tumors using a multidisciplinary approach. Proper administration of HDR-IORT requires institutional support and a joint effort among physics staff, oncologists, surgeons, anesthesiologists, and nurses. In order to determine the true efficacy of IORT for various malignancies, collaboration among institutions with established IORT programs is needed. [ABSTRACT FROM AUTHOR]

Skeletal muscle atrophy can occur as a consequence of immobilization and/or starvation in the majority of vertebrates studied. In contrast, hibernating mammals are protected against the loss of muscle mass despite long periods of inactivity and lack of food intake. Resident muscle-specific stem cells (satellite cells) are known to be activated by muscle injury and their activation contributes to the regeneration of muscle, but whether satellite cells play a role in hibernation is unknown. In the hibernating 13-lined ground squirrel we show that muscles ablated of satellite cells were still protected against atrophy, demonstrating that satellite cells are not involved in the maintenance of skeletal muscle during hibernation. Additionally, hibernating skeletal muscle showed extremely slow regeneration in response to injury, due to repression of satellite cell activation and myoblast differentiation caused by a fine-tuned interplay of p21, myostatin, MAPK, and Wnt signaling pathways. Interestingly, despite long periods of inflammation and lack of efficient regeneration, injured skeletal muscle from hibernating animals did not develop fibrosis and was capable of complete recovery when animals emerged naturally from hibernation. We propose that hibernating squirrels represent a new model system that permits evaluation of impaired skeletal muscle remodeling in the absence of formation of tissue fibrosis. [ABSTRACT FROM AUTHOR]

The article focuses on the study of Winkfield and Harris regarding the association between local control (LC) and overall survival (OS) in breast cancer patients. The researchers counter the dogmatic impression embedded on the predominant theories through their data that support the link between LC and OS based on the 2005 Early Breast Cancer Trialists' Collaborative Group meta-analysis result. The author notes that only time will tell whether the link between LC and OS will be accepted.

Purpose: The success of partial breast irradiation critically depends on proper target localization. We examined the use of fluorodeoxyglucose-positron emission tomography (FDG-PET)/computed tomography (CT) for improved lumpectomy cavity (LC) delineation and treatment planning. Methods and Materials: Twelve breast cancer patients underwent FDG-PET/CT on a GE Discovery scanner with a median time from surgery to PET/CT of 49 days. The LC was contoured on the CT scan by a radiation oncologist and, together with a nuclear medicine physician, on the PET/CT scan. The volumes were calculated and compared in each patient. Treatment planning target volumes (PTVs) were calculated by expanding the margin 2 cm beyond the LC, maintaining a 5-mm margin from the skin and chest wall, and the treatment plans were evaluated. In addition, a study with a patient-like phantom was conducted to evaluate the effect that the window/level settings might have on contouring. Results: The margin of the LC was well visualized on all FDG-PET images. The phantom results indicated that the difference between the known volume and the FDG-PET-delineated volume was <10%, regardless of the window/level settings. The PET/CT volumes were larger than the CT volumes in all cases (median volume ratio, 1.68; range, 1.24–2.45; p = 0.004). The PET/CT-based PTVs were also larger than the CT-based PTV (median volume ratio, 1.16; range, 1.08–1.64; p = 0.006). In 9 of 12 patients, a CT-based treatment plan did not provide adequate coverage of the PET/CT-based PTV (99% of the PTV received <95% of the prescribed dose), resulting in substantial cold spots in some plans. In these cases, treatment plans were generated which were specifically designed to cover the larger PET/CT-based PTV. Although these plans showed an increased dose to the normal tissues, the increases were modest: the non–target breast volume receiving ≥50 Gy, lung volume receiving ≥30 Gy, and heart volume receiving ≥5 Gy increased by 5.7%, 0.8%, and 0.2%, respectively. The normal tissue dose–volume objectives were still met with these plans. Conclusion: The results of our study have shown that FDG-PET/CT can be used to define the LC volume. The increased FDG uptake was likely a result of postoperative inflammation in the LC. The targets defined using PET/CT were significantly larger than those defined with CT alone. Our results have shown that treatment plans can be generated to cover these larger PET/CT target volumes with only a modest increase in irradiated tissue volume compared with CT-determined PTVs. [Copyright &y& Elsevier]