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Purpose Eliminating patient computed tomography (CT) scans for tandem and ring (T&R) brachytherapy can reduce overall procedure time and eliminates imaging dose. However, reconstructing titanium applicators in magnetic resonance imaging (MRI) is challenging. We evaluated the uncertainty of different applicator reconstruction workflows in MR-guided brachytherapy, and assessed the clinical impact of reconstruction uncertainties. Methods and materials Titanium MRI-compatible T&Rs with aqueous gel in the buildup cap were reconstructed on CTs and MRIs to assess the uncertainties of four different workflows. Reconstruction was performed using (1) proton density–weighted MRIs with solid applicator from a library, (2) applicator-only reference CT fused with MRIs, (3) T2-weighted (T2W) MRIs following GEC-ESTRO guidelines, and (4) patient CTs fused with patient MRIs with in situ applicators. We evaluated dwell positions and plan quality differences using high-risk clinical target volume coverage, and EQD2 D2cc of rectum, sigmoid, bladder, and small bowel. Results The 2σ uncertainty for dwell positions for each workflow were (1) 2.7 mm for both ring and tandem, (2) 1.4 mm ring and 0.8 mm tandem, (3) 0.2 mm ring and 0.8 mm tandem, and (4) 1.9 mm ring and 0.4 mm tandem. Reconstruction uncertainties resulted in dose variations within acceptable levels (below 10%) except for (1) which resulted in larger dose to the rectum (20%). Dose uncertainties were similar between reference CT and patient CT. Conclusions Reconstruction with a reference CT results in similar uncertainty to a patient CT. T2W MRI plans have acceptable uncertainty levels for the applicator reconstruction and resulting dose distributions.

Palliative radiotherapy is an effective treatment in alleviating many symptoms of advanced cancer. Short courses of radiotherapy provide rapid symptom relief and minimize impact on patients. Patients referred for palliative radiotherapy have many concerns beyond radiotherapy; often, these concerns are not fully addressed in traditional radiotherapy clinics. Discussions of prognosis, patient goals, and concerns are areas for improved collaboration. Innovative, dedicated palliative radiotherapy programs have developed over the past 20 years to provide holistic care to patients referred for palliative radiotherapy and have improved patient-focused outcomes. Advanced radiotherapy techniques may provide opportunities to further improve palliative radiotherapy outcomes.

Purpose: This study evaluates the toxicity and tumor response with concurrent nab-paclitaxel chemoradiotherapy (CRT) compared with standard (5-fluorouracil or gemcitabine) CRT. Materials and Methods: Fifty patients with borderline resectable or unresectable pancreatic adenocarcinoma from 2014 to 2017 were divided into 2 groups: concurrent nab-paclitaxel (100 to 125 mg/m2 weekly) CRT (median: 2.1 Gy fraction size and 52.5 Gy total) or standard CRT (median: 1.8 Gy fraction size, 54.5 Gy total). The primary endpoint was toxicity, and secondary endpoints were local failure and conversion to resectability. Comparisons were made using rank-sum or Fisher exact test and multivariable competing risk regression for the cumulative incidence of local failure. Results: There were 28 patients in the nab-paclitaxel CRT group and 22 in the standard CRT group; 88% had the unresectable disease. The median follow-up was 18 months. The median duration of chemotherapy before concurrent CRT was 1.9 and 2.3 months in the nab-paclitaxel and standard CRT groups (P=0.337), and radiotherapy dose was 52.5 Gy (range, 52.5 to 59.4 Gy) and 54.5 Gy (range, 45.0 to 59.4 Gy), respectively. There were no statistically significant grade ≥2 toxicities. The nab-paclitaxel CRT group experienced a nonstatistically significant lower incidence of local failure (hazard ratio=0.91, 95% confidence interval: 0.27-3.03, P=0.536). More patients in the nab-paclitaxel CRT group proceeded to surgery (9/28 compared with 3/22 in the standard CRT, P=0.186); of which 6 (25%) in the nab-paclitaxel CRT and 2 (10%) in the standard CRT groups were initially unresectable. Conclusions: Nab-paclitaxel CRT had similar toxicity compared with standard CRT in the treatment of borderline resectable or unresectable pancreatic cancer. Its use was associated with an arithmetically lower cumulative incidence of local failure and an arithmetically higher conversion to resectability, both of which were not statistically significant.

Palliative radiotherapy is an effective treatment in alleviating many symptoms of advanced cancer. Short courses of radiotherapy provide rapid symptom relief and minimize impact on patients. Patients referred for palliative radiotherapy have many concerns beyond radiotherapy; often, these concerns are not fully addressed in traditional radiotherapy clinics. Discussions of prognosis, patient goals, and concerns are areas for improved collaboration. Innovative, dedicated palliative radiotherapy programs have developed over the past 20 years to provide holistic care to patients referred for palliative radiotherapy and have improved patient-focused outcomes. Advanced radiotherapy techniques may provide opportunities to further improve palliative radiotherapy outcomes.