Emma B. Holliday

Proton Radiation Therapy for Head and Neck Cancer: A Review of the Clinical Experience to Date

Proton beam radiation has been used for cancer treatment since the 1950s, but recent increasing interest in this form of therapy and the construction of hospital-based and clinic-based facilities for its delivery have greatly increased both the number of patients and the variety of tumors being treated with proton therapy. The mass of proton particles and their unique physical properties (ie, the Bragg peak) allow proton therapy to spare normal tissues distal to the tumor target from incidental irradiation. Initial observations show that proton therapy is particularly useful for treating tumors in challenging locations close to nontarget critical structures. Specifically, improvements in local control outcomes for patients with chordoma, chonodrosarcoma, and tumors in the sinonasal regions have been reported in series using proton. Improved local control and survival outcomes for patients with cancer of the head and neck region have also been seen with the advent of improvements in better imaging and multimodality therapy comprising surgery, radiation therapy, and chemotherapy. However, aggressive local therapy in the proximity of critical normal structures to tumors in the head and neck region may produce debilitating early and late toxic effects. Great interest has been expressed in evaluating whether proton therapy can improve outcomes, especially early and late toxicity, when used in the treatment of head and neck malignancies. This review summarizes the progress made to date in addressing this question.

Gender differences in publication productivity, academic position, career duration, and funding among U.S. Academic radiation oncology faculty

Purpose This study aimed to analyze gender differences in rank, career duration, publication productivity, and research funding among radiation oncologists at U.S. academic institutions. Method For 82 domestic academic radiation oncology departments, the authors identified current faculty and recorded their academic rank, degree, and gender. The authors recorded bibliographic metrics for physician faculty from a commercially available database (Scopus, Elsevier BV), including numbers of publications from 1996 to 2012 and h-indices. The authors then concatenated these data with National Institutes of Health (NIH) funding per Research Portfolio Online Reporting Tools. The authors performed descriptive and correlative analyses, stratifying by gender and rank. Results Of 1,031 faculty, 293 (28%) women and 738 (72%) men, men had a higher median m-index, 0.58 (range 0–3.23) versus 0.47 (0–2.5) (P < .05); h-index, 8 (0–59) versus 5 (0–39) (P < .05); and publication number, 26 (0–591) versus 13 (0–306) (P < .05). Men were more likely to be senior faculty and receive NIH funding. After stratifying for rank, these differences were largely nonsignificant. On multivariate analysis, there were correlations between gender, career duration and academic position, and h-index (P < .01). Conclusions Determinants of a successful career in academic medicine are multifactorial. Data from radiation oncologists show a systematic gender association, with fewer women achieving senior faculty rank. However, women achieving seniority have productivity metrics comparable to those of male counterparts. This suggests that early career development and mentorship of female faculty may narrow productivity disparities.

Postoperative proton therapy for chordomas and chondrosarcomas of the spine: adjuvant versus salvage radiation therapy.

Study Design. Retrospective comparative cohort series. Objective. The aim of this study was to evaluate patients treated with proton therapy for chordoma and chondrosarcoma of the spine in the postoperative setting and to report local control, relapse-free, and overall survival outcomes. Summary of Background Data. Margin-negative resection of spinal chordomas and chondrosarcomas can be challenging, so adjuvant radiotherapy is often recommended. However, delivery of adequate radiotherapy is complicated by the relative radioresistance of these tumors, necessitating high doses, as well as the proximity of the spinal cord and exiting nerve roots increasing the risk for toxicity. Proton radiotherapy has favorable physical properties for avoiding nearby nontarget structures and is increasingly used for such lesions. Methods. Nineteen patients who underwent postoperative proton therapy at a single institution from 2006 to 2012 were identified including 13 with chordoma and 6 with chondrosarcoma. Surgical approach varied by tumor location in the cervical (n = 3), thoracic (n = 1), lumbar (n = 2), or sacral (n = 13) spine. Eight patients were categorized as receiving “early adjuvant” and 11 patients as receiving “salvage” treatment, as determined by initiation of radiation therapy after primary surgery or local recurrence, respectively. The median radiation dose delivered was 70 Gy relative biologic effectiveness (range: 56–78 Gy relative biologic effectiveness). Results. For the entire cohort, 2-year local control, relapse-free survival, and overall survival were 58%, 51.9%, and 93.3%, respectively. The early adjuvant group had significantly higher 2-year local control (80% vs. 45.5%; P = 0.024). Conclusion. Patients referred early for primary adjuvant radiation therapy after surgery had higher rates of disease control than those referred for salvage treatment of recurrent disease. Recurrence rates in our cohort were higher overall than other published series, indicating that even higher radiation doses may be helpful for further improving local control in the presence of gross or recurrent disease. Level of Evidence: 3

Intensity-modulated proton beam therapy (IMPT) versus intensity-modulated photon therapy (IMRT) for patients with oropharynx cancer - A case matched analysis.

BACKGROUND Owing to its physical properties, intensity-modulated proton therapy (IMPT) used for patients with oropharyngeal carcinoma has the ability to reduce the dose to organs at risk compared to intensity-modulated radiotherapy (IMRT) while maintaining adequate tumor coverage. Our aim was to compare the clinical outcomes of these two treatment modalities. METHODS We performed a 1:2 matching of IMPT to IMRT patients. Our study cohort consisted of IMPT patients from a prospective quality of life study and consecutive IMRT patients treated at a single institution during the period 2010-2014. Patients were matched on unilateral/bilateral treatment, disease site, human papillomavirus status, T and N status, smoking status, and receipt of concomitant chemotherapy. Survival analyzes were performed using a Cox model and binary toxicity endpoints using a logistic regression analysis. RESULTS Fifty IMPT and 100 IMRT patients were included. The median follow-up time was 32months. There were no imbalances in patient/tumor characteristics except for age (mean age 56.8years for IMRT patients and 61.1years for IMPT patients, p-value=0.010). Statistically significant differences were not observed in overall survival (hazard ratio (HR)=0.55; 95% confidence interval (CI): 0.12-2.50, p-value=0.44) or in progression-free survival (HR=1.02; 95% CI: 0.41-2.54; p-value=0.96). The age-adjusted odds ratio (OR) for the presence of a gastrostomy (G)-tube during treatment for IMPT vs IMRT were OR=0.53; 95% CI: 0.24-1.15; p-value=0.11 and OR=0.43; 95% CI: 0.16-1.17; p-value=0.10 at 3months after treatment. When considering the pre-planned composite endpoint of grade 3 weight loss or G-tube presence, the ORs were OR=0.44; 95% CI: 0.19-1.0; p-value=0.05 at 3months after treatment and OR=0.23; 95% CI: 0.07-0.73; p-value=0.01 at 1year after treatment. CONCLUSION Our results suggest that IMPT is associated with reduced rates of feeding tube dependency and severe weight loss without jeopardizing outcome. Prospective multicenter randomized trials are needed to validate such findings.

Proton Therapy Reduces Treatment-Related Toxicities for Patients with Nasopharyngeal Cancer: A Case-Match Control Study of Intensity-Modulated Proton Therapy and Intensity-Modulated Photon Therapy

Abstract Purpose: The physical properties of proton therapy allow for decreased dose delivery to nontarget structures. The purpose of this study was to determine if this translates into a clinical benefit by comparing acute and chronic morbidity between patients with nasopharyngeal carcinoma who are treated with intensity-modulated proton therapy (IMPT) and those treated with intensity-modulated radiation therapy (IMRT). Materials and Methods: Patients receiving IMPT for nasopharyngeal cancer from 2011-13 were matched in a 2:1 IMPT to IMRT ratio. Matching criteria were, in order, T-stage, N-stage, radiation dose, chemotherapy type, World Health Organization classification, sex, and age. Results: Ten patients treated with IMPT and 20 matched patients treated with IMRT were included. By the end of treatment, 2 IMPT-treated patients (20%) and 13 IMRT-treated patients (65%) required gastrostomy tube (GT) insertion (P = .020). Patients receiving IMPT had significantly lower mean doses to the oral cavity, brain...

Attracting Future Radiation Oncologists: An Analysis of the National Resident Matching Program Data Trends From 2004 to 2015

PURPOSE A significant physician shortage has been projected to occur by 2025, and demand for oncologists is expected to outpace supply to an even greater degree. In response to this, many have called to increase the number of radiation oncology residency positions. The purpose of this study is to evaluate National Resident Matching Program (NRMP) data for the number of residency positions between 2004 and 2015 as well as the number and caliber of applicants for those positions and to compare radiation oncology to all residency specialties. METHODS NRMP data for all specialties participating in the match, including radiation oncology, were assessed over time examining the number of programs participating in the match, the number of positions offered, and the ratio of applicants to positions in the match from 2004 to 2015. RESULTS From 2004 to 2015, the number of total programs participating in the match has increased by 26.7%, compared to the increase of 28.6% in the number of radiation oncology programs from during the same time period. The total number of positions offered in the match increased by 53.4%, whereas radiation oncology positions increased by 56.3%, during the same time period. The ratio of applicants (defined as those selecting a specialty as their first or only choice) to positions for all specialties has fluctuated over this time period and has gone from 1.21 to 1.15, whereas radiation oncology experienced a decrease from 1.45 to 1.14. CONCLUSIONS NRMP data suggest that senior medical student applications to radiation oncology are decreasing compared to those of other specialties. If we hope to continue to attract the best and brightest to enter our field, we must continue to support early exposure to radiation oncology, positive educational experiences, and dedicated mentorship to interested medical students.

Dosimetric advantages of intensity-modulated proton therapy for oropharyngeal cancer compared with intensity-modulated radiation: A case-matched control analysis

A potential advantage of intensity-modulated proton therapy (IMPT) over intensity-modulated (photon) radiation therapy (IMRT) in the treatment of oropharyngeal carcinoma (OPC) is lower radiation dose to several critical structures involved in the development of nausea and vomiting, mucositis, and dysphagia. The purpose of this study was to quantify doses to critical structures for patients with OPC treated with IMPT and compare those with doses on IMRT plans generated for the same patients and with a matched cohort of patients actually treated with IMRT. In this study, 25 patients newly diagnosed with OPC were treated with IMPT between 2011 and 2012. Comparison IMRT plans were generated for these patients and for additional IMRT-treated controls extracted from a database of patients with OPC treated between 2000 and 2009. Cases were matched based on the following criteria, in order: unilateral vs bilateral therapy, tonsil vs base of tongue primary, T-category, N-category, concurrent chemotherapy, induction chemotherapy, smoking status, sex, and age. Results showed that the mean doses to the anterior and posterior oral cavity, hard palate, larynx, mandible, and esophagus were significantly lower with IMPT than with IMRT comparison plans generated for the same cohort, as were doses to several central nervous system structures involved in the nausea and vomiting response. Similar differences were found when comparing dose to organs at risks (OARs) between the IMPT cohort and the case-matched IMRT cohort. In conclusion, these findings suggest that patients with OPC treated with IMPT may experience fewer and less severe side effects during therapy. This may be the result of decreased beam path toxicities with IMPT due to lower doses to several dysphagia, odynophagia, and nausea and vomiting-associated OARs. Further study is needed to evaluate differences in long-term disease control and chronic toxicity between patients with OPC treated with IMPT in comparison to those treated with IMRT.

Standing on the Shoulders of Giants: Results From the Radiation Oncology Academic Development and Mentorship Assessment Project (ROADMAP)

PURPOSE To analyze survey information regarding mentorship practices and cross-correlate the results with objective metrics of academic productivity among academic radiation oncologists at US Accreditation Council for Graduate Medical Education (ACGME)-accredited residency training programs. METHODS AND MATERIALS An institutional review board-approved survey for the Radiation Oncology Academic Development and Mentorship Assessment Project (ROADMAP) was sent to 1031 radiation oncologists employed at an ACGME-accredited residency training program and administered using an international secure web application designed exclusively to support data capture for research studies. Data collected included demographics, presence of mentorship, and the nature of specific mentoring activities. Productivity metrics, including number of publications, number of citations, h-index, and date of first publication, were collected for each survey respondent from a commercially available online database, and m-index was calculated. RESULTS A total of 158 academic radiation oncologists completed the survey, 96 of whom reported having an academic/scientific mentor. Faculty with a mentor had higher numbers of publications, citations, and h- and m-indices. Differences in gender and race/ethnicity were not associated with significant differences in mentorship rates, but those with a mentor were more likely to have a PhD degree and were more likely to have more time protected for research. Bivariate fit regression modeling showed a positive correlation between a mentors h-index and their mentees h-index (R2=0.16; P<.001). Linear regression also showed significant correlates of higher h-index, in addition to having a mentor (P=.001), included a longer career duration (P<.001) and fewer patients in treatment (P=.02). CONCLUSIONS Mentorship is widely believed to be important to career development and academic productivity. These results emphasize the importance of identifying and striving to overcome potential barriers to effective mentorship.

Gender differences in publication productivity, academic rank, and career duration among U.S. academic gastroenterology faculty

Purpose Female representation in academic medicine is increasing without proportional increases in female representation at senior ranks. The purpose of this study is to describe the gender representation in academic gastroenterology (GI) and compare publication productivity, academic rank, and career duration between male and female gastroenterologists. Method In 2014, the authors collected data including number of publications, career duration, h-index, and m-index for faculty members at 114 U.S. academic GI programs. Results Of 2,440 academic faculty, 1,859 (76%) were men and 581 (24%) were women. Half (50%) of men held senior faculty position compared with 29% of women (P < .001). Compared with female faculty, male faculty had significantly (P < .001) longer careers (20 vs. 11 years), more publications (median 24 [0–949] vs. 9 [0–438]), and higher h-indices (8 vs. 4). Higher h-index correlated with higher academic rank (P < .001). The authors detected no difference in the h-index between men and women at the same rank for professor, associate professor, and instructor, nor any difference in the m-index between men and women (0.5 vs. 0.46, respectively, P = .214). Conclusions A gender gap exists in the number and proportion of women in academic GI; however, after correcting for career duration, productivity measures that consider quantity and impact are similar for male and female faculty. Women holding senior faculty positions are equally productive as their male counterparts. Early and continued career mentorship will likely lead to continued increases in the rise of women in academic rank.

Publication productivity and experience: Factors associated with academic rank among orthopaedic surgery faculty in the United States

BACKGROUND Many factors play a role in academic promotion among orthopaedic surgeons. This study specifically examined the importance of publication productivity metrics, career duration, and sex on academic rank in orthopaedic surgery programs in the United States. METHODS Faculty at 142 civilian academic orthopaedic surgery departments in 2014 were identified. Geographic region, department size, and 3 specific faculty characteristics (sex, career duration, and academic position) were recorded. The Hirsch index (h-index), defined as the number (h) of an investigators publications that have been cited at least h times, was recorded for each surgeon. The m-index was also calculated by dividing the h-index by career duration in years. Thresholds for the h-index and the m-index were identified between junior and senior academic ranks. Multivariate analysis was used to determine whether the 3 physician factors correlated independently with academic rank. RESULTS The analysis included 4,663 orthopaedic surgeons at 142 academic institutions (24.7% clinical faculty and 75.3% academic faculty). Among academic faculty, the median h-index was 5, the median career duration was 15 years, and the median m-index was 0.37. Thresholds between junior and senior faculty status were 12 for the h-index and 0.51 for the m-index. Female academic faculty had a lower median h-index (3 compared with 5; p < 0.001) and career duration (10 years compared with 16 years; p < 0.001) than male academic faculty, but had a similar median m-index (0.33 compared with 0.38; p = 0.103). A higher h-index and longer career duration correlated independently with an increased probability of senior academic rank (p < 0.001), but sex did not (p = 0.217). CONCLUSIONS This analysis demonstrates that a higher h-index and m-index correlate with a higher academic orthopaedic faculty rank. Although female surgeons had a lower median h-index and a shorter median career duration than male surgeons, their m-index was not significantly different, and thus sex was not an independent predictor for senior academic rank. The identified thresholds (h-index of 12 and m-index of 0.51) between junior and senior academic ranks may be considered as factors in promotion considerations.