Perceptions of Canadian Radiation Oncologists, Medical Physicists, and Radiation Trainees about the Feasibility and Need of Boron Neutron Capture Therapy (BNCT) in Canada: A National Survey.

BACKGROUND: Boron Neutron Capture Therapy (BNCT) is an emerging radiotherapy. There are ongoing efforts to develop a Canadian accelerator-based BNCT center. However, it remains unclear how Canadian radiation oncologists (RO), medical physicists (MP), and their trainees perceive BNCT and its impact on radiation oncology as a discipline. METHODS: A survey was created to explore the knowledge of BNCT, its clinical role, and the support for Canadian research. It was distributed through the Canadian Association of Radiation Oncology (CARO) and the Canadian Organization of Medical Physicists (COMP). RESULTS: We received 118 valid responses from all 10 provinces, from 70 RO (59.3%) and 48 MP (40.7%), including 9 residents. Most knew of BNCT and its indications (60.2%). Although many were unaware of the reasons behind early failures (44.1%), common reasons were a lack of clinical trials and an inaccessibility of neutron sources (42.4%) as well as reactor unsuitability (34.7%). Additionally, 90.6% showed definite (66.9%) or possible (23.7%) support for Canadian BNCT research, while 89% indicated a definite (56.8%) or possible (32.2%) willingness for BNCT referrals. CONCLUSIONS: Most ROs and MPs supported Canadian BNCT research and would refer patients. However, limited awareness and a lack of experiences remain a challenge. Educational sessions are needed to realize this innovative cancer treatment in Canada.

COMP Report: CPQR technical quality control guidelines for use of positron emission tomography/computed tomography in radiation treatment planning.

Positron emission tomography with x-ray computed tomography (PET/CT) is increasingly being utilized for radiation treatment planning (RTP). Accurate delivery of RT therefore depends on quality PET/CT data. This study covers quality control (QC) procedures required for PET/CT for diagnostic imaging and incremental QC required for RTP. Based on a review of the literature, it compiles a list of recommended tests, performance frequencies, and tolerances, as well as references to documents detailing how to perform each test. The report was commissioned by the Canadian Organization of Medical Physicists as part of the Canadian Partnership for Quality Radiotherapy initiative.

Early-Stage Non-Small Cell Lung Cancer Stereotactic Body Radiation Therapy Outcomes in a Single Institution.

Introduction The gold standard treatment of stage I non-small cell lung cancer (NSCLC) is surgical resection. For medically inoperable patients, stereotactic body radiation therapy (SBRT) can provide comparable local control (LC) and overall survival (OS). The objectives of this study are to determine the three-year LC and OS for SBRT compared to early-stage NSCLC patients treated with alternative radiation modalities at our institution. Materials and methods This retrospective study included a total of 139 consecutive patients who were diagnosed with stage I (T1-2 N0 M0) NSCLC and treated with radiation therapy at our institution between 2015 and 2020. Patient demographics and clinical data were obtained from chart reviews. Treatment subgroups were: SBRT (48Gy/4 or 60Gy/8), hypofractionation (60Gy/15), conventional fractionation (60Gy/30 or 50Gy/20), and palliative radiation (20Gy/5, 30Gy/10, or 40Gy/15). Kaplan-Meier curves were plotted for LC and OS. We also performed Cox's proportional hazard regression analysis. Results The median patient age was 74 (range 52-91). The numbers of patients in each treatment subgroup were: SBRT (44), hypofractionation (78), conventional fractionation (8), and palliative (9). Differences in age, gender, and histopathological cell type between subgroups were not statistically significant. Metastatic progression was the most common outcome amongst treatment failures, followed by local recurrence and regional spread. Median post-treatment follow-up in months for each subgroup was: SBRT (20.2), hypofractionated (20.7), conventional fractionation (13.9), and palliative (14.4). Post-treatment three-year LC was found to be significantly better with SBRT (94%) versus hypofractionation (71%), conventional fractionation (80%), and palliative (71%). OS at three years were SBRT (67%), hypofractionation (59%), conventional fractionation (66%), and palliative (44%). As a whole, 72% (100/139) of patients had biopsy-proven NSCLC. Analysis showed biopsy status had no statistical significance with regards to LC or OS. Every 20 years of age had a 3.2x risk of death (95% CI: 1.425-7.268). Concerning the treatment modalities, there were significant differences for the hazard of death compared to SBRT: hypofractionation had 2.58x increased risk while palliative had 5.83x increased risk. The proportion of patients who experienced post-treatment radiation pneumonitis or dermatitis were: SBRT (7%, 2%), hypofractionation (8%, 3%), conventional fractionation (13%, 25%), and palliative (0%, 0%), respectively. No patients who experienced grade III or higher toxicities were observed as defined by Common Terminology Criteria for Adverse Events (CTCAE).  Conclusion Our experience confirms SBRT can provide durable three-year local control with a comparable rate of post-treatment complications versus other radiation modalities for early-stage NSCLC. SBRT appears to be non-inferior to hypofractionation with regards to three-year LC.

On the possible benefits of a hybrid VMAT technique in the treatment of non-small cell lung cancer.

To assess, using clinical cases, the potential of a hybrid technique for the treatment of non-small cell lung cancer (NSCLC)-blending volumetric-modulated arc therapy (VMAT) and conformal radiation therapy (CRT) fields, and to consider potential issues with implementation of such a technique. Eight clinical cases already treated with CRT were used for a planning study comparing target coverage and organs at risk (OAR) sparing between CRT and hybrid VMAT (VMATh). Quality assurance (QA) implications of the resultant hybrid plans are discussed. The hybrid technique resulted in superior target conformity or improved sparing of OAR or both. The hybrid technique shows promise, but the QA implications of motion at treatment need careful consideration.