Analysis of Retrospective Versus Prospective Peer Review in a Multisite Academic Radiation Department.

Purpose: Our multisite academic radiation department reviewed our experience with transitioning from weekly primarily retrospective to daily primarily prospective peer review to improve plan quality and decrease the rate of plan revisions after treatment start. Methods and Materials: This study was an institutional review board-approved prospective comparison of radiation treatment plan review outcomes of plans reviewed weekly (majority within 1 week after treatment start) versus plans reviewed daily (majority before treatment start, except brachytherapy, frame-based radiosurgery, and some emergent plans). Deviations were based on peer comments and considered major if plan revisions were recommended before the next fraction and minor if modifications were suggested but not required. Categorical variables were compared using χ2 distribution tests of independence; means were compared using independent t tests. Results: In all, 798 patients with 1124 plans were reviewed: 611 plans weekly and 513 plans daily. Overall, 76 deviations (6.8%) were noted. Rates of any deviation were increased in the daily era (8.6% vs 5.2%; P = .026), with higher rates of major deviations in the daily era (4.1% vs 1.6%; P = .012). Median working days between initial simulation and treatment was the same across eras (8 days). Deviations led to a plan revision at a higher rate in the daily era (84.1% vs 31.3%; P < .001). Conclusions: Daily prospective peer review is feasible in a multisite academic setting. Daily peer review with emphasis on prospective plan evaluation increased constructive plan feedback, plan revisions, and plan revisions being implemented before treatment start.

Patient characteristics and clinical factors affecting lumpectomy cavity volume: implications for partial breast irradiation.

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.

Progression of citation-based scholarly activity from postgraduate year one to postgraduate year two in a current resident class.

BACKGROUND: Recent work has demonstrated multiple measures of citation-based scholarly activity. Measures including Hirsch index (h-index), h-index limited to first author manuscripts (hf), h-index limited to first or second author only manuscripts (hs), and g-index have been associated with radiation oncology resident choice of academic versus private practice career. To date, there has been no evaluation of the progression of citation-based scholarly activity during residency. METHODS: A list of United States radiation oncology residents from the graduating class of 2022 [postgraduate year two (PGY-2) academic year of 2018-2019] was obtained through internet investigation. Citation-based scholarly activity was collected and calculated from searches of the Scopus bibliometric citation database for h-index, hf, hs, and g-index for each resident as previously described. Calculations were derived in June 2018 for the postgraduate year one (PGY-1) year, and in June 2019 for the PGY-2 year. Fisher's exact test was used for statistical analysis. RESULTS: Analysis of 195 residents from the 2022 class revealed that the citation-based scholarly activity significantly increased from PGY-1 to PGY-2 for h-index (2.6 to 3.2; P=0.047) and g-index (4.0 to 5.1; P=0.045), but not for hf (1.0 to 1.3; P=0.170) or hs (1.5 to 1.9; P=0.065). Underrepresented minority race/ethnicity (African-American/Hispanic) did not impact the significance of the h-index and g-index findings. CONCLUSIONS: From the PGY-1 to PGY-2 academic year, residents significantly increased in citation-based academic productivity, with an increase in the proportion of residents with a cited first-or-second author manuscript. Further study is necessary to determine how this trend persists in future years.

Evolution of the prevalence of pre-residency peer-reviewed publications among incoming junior residents.

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.

Composition of the Current Academic Radiation Oncology Workforce in Comprehensive Cancer Centers.

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 = 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 = .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 = .02). The mean h-index for all faculty is 17.6 (standard deviation = 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.

Gender-based analysis of pre-residency research productivity among a current United States radiation oncology resident class.

BACKGROUND: The increasing proportion of women in medicine has not been adequately reflected in the gender distribution of radiation oncology residents. The presence of at least one pre-residency peer-reviewed publication (PRP) has been associated with radiation oncology resident choice of academic over private practice career, with no significant gender difference in the likelihood of having a PRP (McClelland et al., 2017). We sought to pursue a gender-based analysis of PRP productivity in a current junior resident class. METHODS: A list of radiation oncology residents from the graduating class of 2022 (PGY-2 academic year of 2018-2019) was obtained through internet investigation. Research productivity was calculated using PRP number, defined as the number of a resident's publications listed in PubMed (pubmed.gov) through the calendar year of residency application (2016 for this class). RESULTS: Of 195 residents examined from the 2022 class, 61 (31%) were women, representing a nine percent increase from the resident class of 2016. Four-fifths of women had 1+ PRP, 31% had dual degrees, and 18% had a PhD. These percentages were comparable to their male counterparts, 73% with 1+ PRP, 28% with dual degrees, and 15% with a PhD. There were no statistically significant differences by gender in any of these benchmarks. CONCLUSIONS: While slower than the overall trend of increased female representation in medicine, the proportion of women in radiation oncology residency has increased by 0.9-1.5% annually over a recent six-year span. There remain no significant differences in PRP productivity, dual degree status, or PhD status by gender.

Integrating Radiation Oncology Into Undergraduate Medical Education.

Cancer is one of the most important public health problems. However, medical education has not advanced at the same rate when it comes to cancer education. Currently, the United States Medical Licensing Examination subject examinations do not cover radiation oncology, prevention, and survivorship planning in its assessment model. Incorporating medical oncology and radiation oncology training into the undergraduate medical education curriculum can have a significant benefit in training future physicians. In this paper, we review current literature and propose some ideas that can help incorporate oncology, and specifically radiation oncology, into undergraduate medical education.

Demographic factors associated with missed follow-up among solid tumor patients treated at a large multi-site academic institution.

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.

Predictors of Whole Breast Radiation Therapy Completion in Early Stage Breast Cancer Following Lumpectomy.

BACKGROUND: Whole breast radiation therapy (RT) has become standard of care in early stage breast cancer treatment following lumpectomy. Predictors of RT completion have been sparsely studied, with no previous nationwide examination of the impact of fractionation regimen on completion rate. PATIENTS AND METHODS: The National Cancer Database identified patients with early stage breast cancer having undergone lumpectomy and RT from 2004 through 2015. Fraction size of 1.8-2.0 Gray (Gy) was defined as standard fractionation (SFRT); 2.66-2.70 Gy/fraction as hypofractionation (HFRT). RT completion was defined as receipt of at least 46 Gy for SFRT and 40 Gy for HFRT. A multivariable logistic regression model characterized RT completion predictors. RESULTS: A total of 100,734 patients were identified where fraction size could be reliably characterized as above; more than 87% completed RT. Of these, 66.8% received SFRT, yet HFRT use significantly increased over time (5.2% increase/year; P < .0001). RT completion rates were significantly greater following HFRT (99.3%) versus SFRT (79.7%); patients receiving SFRT had higher odds of not completing RT (odds ratio, 41.5; 95% confidence interval, 36.6-47.1; P < .0001). Multivariable analysis revealed that African-American and Caucasian patients treated with SFRT versus HFRT had 22 and 43 times the odds of not completing RT, respectively (P < .0001). CONCLUSIONS: SFRT remained the majority of RT fractionation in the studied time period, although HFRT use has increased over time. Patients residing > 10 miles from a treatment facility or of African-American race had lower odds of completing RT, as were patients treated with SFRT versus HFRT. These findings suggest compliance advantages of HFRT for patients with early stage breast cancer having undergone lumpectomy.

Baseline Karnofsky performance status is independently predictive of death within 30 days of intracranial radiation therapy completion for metastatic disease.

INTRODUCTION: For patients with brain metastases, palliative radiation therapy (RT) has long been a standard of care for improving quality of life and optimizing intracranial disease control. The duration of time between completion of palliative RT and patient death has rarely been evaluated. METHODS: A compilation of two prospective institutional databases encompassing April 2015 through December 2018 was used to identify patients who received palliative intracranial radiation therapy. A multivariate logistic regression model characterized patients adjusting for age, sex, admission status (inpatient versus outpatient), Karnofsky Performance Status (KPS), and radiation therapy indication. RESULTS: 136 consecutive patients received intracranial palliative radiation therapy. Patients with baseline KPS <70 (OR = 2.2; 95%CI = 1.6-3.1; p < 0.0001) were significantly more likely to die within 30 days of treatment. Intracranial palliative radiation therapy was most commonly delivered to provide local control (66% of patients) or alleviate neurologic symptoms (32% of patients), and was most commonly delivered via whole brain radiation therapy in 10 fractions to 30 Gy (38% of patients). Of the 42 patients who died within 30 days of RT, 31 (74%) received at least 10 fractions. CONCLUSIONS: Our findings indicate that baseline KPS <70 is independently predictive of death within 30 days of palliative intracranial RT, and that a large majority of patients who died within 30 days received at least 10 fractions. These results indicate that for poor performance status patients requiring palliative intracranial radiation, hypofractionated RT courses should be strongly considered.

Analysis of pre-residency research productivity, dual degree status, and gender distribution of underrepresented minorities among a current United States radiation oncology junior resident class.

BACKGROUND: Among the most competitive medical subspecialties, representation of underrepresented minorities (African-American race and/or Hispanic ethnicity) among resident trainees has historically been low compared to their United States Census general population representation. Research productivity and dual degree status may impact residency applicant competitiveness. To date, such an analysis has yet to be performed in Radiation Oncology. METHODS: A list of radiation oncology residents from the graduating class of 2022 was obtained through internet searches. Demographics included were gender and dual degree status. Research productivity was calculated using the number of pre-residency peer-reviewed publications (PRP). Fisher's exact test was used for statistical analysis. RESULTS: Of the 179 residents evaluated from the 2022 class, eleven (6.1%) were underrepresented minorities. Compared to the remainder of the class, underrepresented minorities had a lower proportion of men (63.6% versus 69.3%), a higher proportion of dual degrees (45.5% versus 28.6%), and a lower proportion of MD-PhD degrees (9.1% versus 17.2%). Underrepresented minorities had a higher proportion of residents with at least two PRP (72.7% versus 57.1%) and a lower proportion of residents with no PRP (18.2% versus 24.4%). None of these differences reached statistical significance (p > 0.05). CONCLUSION: Underrepresented minorities were comparable to the remainder of their Radiation Oncology resident class regarding gender distribution, dual degrees status, and likelihood of having at least two peer-reviewed publications cited in PubMed during the calendar year of residency application. Further studies will be needed to determine how these findings translate into future scholarly activity and post-graduate career choice.

Effects of Radiotherapy in Early-Stage, Low-Recurrence Risk, Hormone-Sensitive Breast Cancer.

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.

Simulation Modeling of Cancer Clinical Trials: Application to Omitting Radiotherapy in Low-risk Breast Cancer.

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.

Effects of Proton Center Closure on Pediatric Case Volume and Resident Education at an Academic Cancer Center.

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.