Dysphagia in Head and Neck Radiotherapy: The Influence of Pharyngeal Constrictor Anatomy and Dosimetry.

The goal of this study was to identify which anatomical and dosimetric changes correlated with late patient-reported dysphagia throughout the course of head and neck chemo-radiotherapy treatment. The patient cohort (n = 64) considered oropharyngeal and nasopharyngeal patients treated with curative intent, exhibiting no baseline dysphagia with a follow-up time greater than one year. Patients completed the MD Anderson Dysphagia Inventory during a follow-up visit. A composite score was measured ranging from 20 to 100, with a low score indicating a high symptom burden; a score ≤60 indicated patient-reported dysphagia. The pharyngeal (PCM) and cricopharyngeal constrictor muscles (CPM) were contoured on a planning CT image and adapted to weekly cone-beam CT anatomy using deformable image registration and dose was accumulated using weighted dose-volume histogram curves. The PCM and CPM were examined for volume, thickness, and dosimetric changes across treatment with the results correlated to symptom group. Anatomical evaluation indicated the PCM thickness increased more during treatment for patients with dysphagia, with base of C2 vertebrae (p = 0.04) and superior-inferior middle PCM (p = 0.01) thicknesses indicating a 1.0-1.5 mm increase. The planned and delivered mean dose and DVH metrics to PCM and CPM were found to be within random error measured for the dose accumulation, indicating delivered and planned dose are equivalent. The PCM and CPM organs were found to lie approximately 5 mm closer to high dose gradients in patients exhibiting dysphagia. The volume, thickness, and high dose gradient metrics may be useful metrics to identify patients at risk of late patient-reported dysphagia.

Documentation and incidence of late effects and screening recommendations for adolescent and young adult head and neck cancer survivors treated with radiotherapy.

PURPOSE: A retrospective review of adolescent and young adult (AYA) head and neck cancer (HNC) patients treated with radiation therapy (RT) at British Columbia Cancer  was performed to determine the incidence of late toxicities, the documented late side effects discussed and the screening recommendations provided at the time of transfer of care to primary care providers (PCPs). METHODS: Charts (n = 162) were reviewed for all patients 15 to 35 years at diagnosis with HNC treated with RT from 1960 to 2010 who survived > 5 years after diagnosis. RESULTS: A discussion regarding the risk of long-term side effects was documented in the initial consultation for 85% of patients. The majority of patients (78%) developed > 1 documented late effect. The most common were xerostomia (44%), skin changes (28%), neck fibrosis (22%), nasal crusting (16%), epistaxis (16%), and dental decay (14%). In all, 20% were currently followed or were followed until they died. Of the 80% transferred to their PCP, 14% had a formal discharge summary. For those discharged from British Columbia Cancer, documented recommendations included regular dental care (34%) and screening for hypothyroidism (5%) and second malignancy (4%). CONCLUSIONS: The majority of AYA HNC patients treated with RT developed late side effects, and most PCPs were not sent a discharge summary outlining screening recommendations for delayed late effects. IMPLICATIONS FOR CANCER SURVIVORS: AYA HNC survivors treated with RT are at high risk for late effects and would benefit from a survivorship care plan outlining these risks and screening recommendations.

Local Prostate Radiation Therapy and Symptomatic Local Events in De Novo Metastatic Prostate Cancer.

PURPOSE: Local prostate radiation therapy (LPRT) for low-burden metastatic prostate cancer (mPCa) improves overall survival and is the standard of care. The role of LPRT in reducing symptomatic local events (SLE) remains unclear. We aimed to identify SLE risk factors and to evaluate the association between LPRT and SLE in mPCa. METHODS AND MATERIALS: We conducted a retrospective, population-based cohort study of patients initially diagnosed with mPCa between 2005 and 2016 in a cancer registry. Patient, tumor, and treatment characteristics were obtained from chart review and the cancer registry. The coprimary endpoints were genitourinary (GU) and gastrointestinal (GI) SLE, identified by physician billing claims between 2004 and 2017 for diagnostic or therapeutic procedures potentially related to GU and GI SLE. The effect of LPRT on SLE was evaluated using both recurrent event (Andersen-Gill model) and time-to-first-event sequential landmark analyses. Risk factors for SLE were assessed by multivariable Cox regression. LPRT was defined as ≥40 Gy within 1 year of diagnosis. Metastatic burden was defined per the STAMPEDE trial. RESULTS: Of 1363 patients, 46 (3.4%) received LPRT. Median follow-up was 27.3 and 28.9 months in the control and LPRT groups, respectively. LPRT was associated with less recurrent GU SLE (hazard ratio [HR], 0.34; 95% confidence interval [CI], 0.17-0.67; P = .002), upper tract obstruction (HR, 0.20; 95% CI, 0.05-0.84; P = .03), and cystoscopy (HR, 0.38; 95% CI, 0.15-0.96; P = .04). Metastatic burden was not associated with SLE. CONCLUSIONS: LPRT in mPCa was associated with less recurrent GU SLE, specifically for upper tract obstruction and cystoscopy.

Representation of Women in Canadian Radiation Oncology Trainees and Radiation Oncologists: Progress or Regress?

Purpose: The study objective was to determine the representation of women in Canadian radiation oncology (RO) trainees and the radiation oncologist workforce over time. Methods and Materials: Gender data for Canadian RO trainees (residents and fellows) and radiation oncologists were collected from the Canadian Post-MD Education Registry (1994-2021) and Canadian Medical Association (1994-2019). Visa trainees were excluded. Gender parity was defined as a 1:1 female-to-male ratio. Descriptive statistics were used to summarize the data. Results: Female trainee proportions varied with 2 rising trend periods (1994-1998: 38%-43%, P = .93; 2002-2014: 35%-51%, P = .53) and 2 regression trend periods (1998-2002: 43%-35%, P = .83; 2014-2021: 52%-35%, P = .011). Gender parity was observed in RO trainees between 2012 and 2016. The annual number of RO trainees ranged from 66 to 173 with 2 near-parallel periods of gender-associated growth (1994-1996; 2002-2008) and regression (1997-2001; 2009-2016) followed by gender divergence (2017-2021) with increasing male and decreasing female trainees. Nearly all Canadian regions, except Ontario, reached 50% or higher female representation in RO trainees during the study period. In the radiation oncologist workforce, female representation increased from 20% (54/271) to 37% (217/582) between 1994 and 2019, and all regions and age groups demonstrated higher female representation over time. Within radiation oncologist subgroups, age <35 years old and Quebec region cohorts reached gender parity. Conclusions: Representation of women varied in Canadian RO trainees and has fallen since 2014, whereas female representation generally increased in the radiation oncologist workforce over time. Gender parity was observed in RO trainees, radiation oncologists <35 years old, and radiation oncologists in Quebec. Recent declining female representation among RO trainees is worrisome, and further study is warranted to identify potential gender-based barriers in attracting women to the specialty.

Underutilization of local salvage therapy after radiation therapy for prostate cancer.

OBJECTIVE: To evaluate the rates at which patients are offered and receive local salvage therapy (LST) after failure of primary radiotherapy for localized prostate cancer, as it is the only potentially curative treatment for localized recurrence but appears to be underutilized when compared with androgen-deprivation therapy (ADT) or observation. MATERIALS AND METHODS: Patients with localized prostate cancer who received primary radiotherapy with curative intent between 1999 and 2000 were identified in the British Columbia Tumour Registry. Exclusion criteria included patient age >72 years, prostate-specific antigen>40 ng/ml, and clinical stage T4 at diagnosis. Data on clinicopathologic features, primary therapy, prostate-specific antigen kinetics, and salvage therapy were collected retrospectively. Radiation failure was defined as biochemical recurrence according to the Phoenix criteria or by initiation of salvage therapy. RESULTS: Of 1,782 patients treated in the study period, 1,067 met inclusion criteria. Of these, 257 failed radiation therapy. Radiation therapy failure was managed with observation (>12 mo) in 126 patients and ADT in 119. Of the observed patients, 66 subsequently received ADT. Five patients (1.8%) received LST (3 radical prostatectomy and 2 brachytherapy). CONCLUSIONS: Only 2% of patients relapsing after radiation therapy for localized prostate cancer received LST. Although the benefits of LST are unproven, these findings reveal a possible underutilization of LST and indicate a need for enhanced collaboration between specialties to optimize care of this challenging cohort.