The Impact of Pathological Grade Group 3 on Relapse-free Survival After Salvage Radiotherapy for Postoperative Prostate Cancer.

BACKGROUND/AIM: This retrospective study aimed to investigate the outcomes of relapse-free survival (RFS) after salvage radiation therapy (SRT) to the prostate bed for postoperative biochemical recurrence of prostate cancer. PATIENTS AND METHODS: A total of 87 patients were analyzed. There were 27, 32, and 24 patients with pathological grade groups of 1-2, 3, and 4-5, respectively. SRT doses of 64, 66 or 70 Gy were administered to 24, 3 and 60 patients, respectively. The Kaplan-Meier method was used to estimate time-to-event outcomes. The multiple imputations method was used to impute missing values, and Cox proportional-hazards models were applied for multivariate analyses. RESULTS: The median follow-up period for patients overall was 58.6 months. The 5-year RFS rates of the whole cohort was 59.4% and those for pathological grade groups 1-2, 3 and 4-5 were 88.9%, 37.7% and 39.5%, respectively. In multivariate analyses, higher pathological grade group [4-5 vs. 3 vs. 1-2: hazard radio (HR)=8.65, p<0.01], negative surgical resection margin (positive vs. negative: HR=0.41, p=0.02) and higher pre-salvage treatment serum prostate-specific antigen (cutoff value 0.31 ng/ml: HR=3.50, p<0.01) were significantly associated with poorer RFS. The cumulative incidences of grade 2 or more late rectal bleeding and late hematuria were 4.9% and 8.7%, respectively, at 5 years and 4.9% and 15.7%, respectively, at 8 years. These toxicities occurred only in the 70 Gy-treated arm. CONCLUSION: Our study revealed that pathological grade group 3 prostate cancer patients experienced moderately unfavorable RFS after SRT. Higher radiation doses might increase late toxicities without improving RFS.

Recent Postoperative Radiotherapy for Left-sided Breast Cancer Does Not Increase Mortality of Heart Disease in Asians or Pacific Islanders: SEER Database Analysis.

BACKGROUND/AIM: The purpose of this study was to evaluate the impact of recent radiotherapy on mortality from heart disease in Asians or Pacific islanders with breast cancer using the Surveillance, Epidemiology, and End Results (SEER) database. PATIENTS AND METHODS: Asians or Pacific islanders with stage 0 or I (AJCC 6th) breast cancer between 2000 and 2015 were analyzed. The impact of radiotherapy for mortality from heart disease after treatment was evaluated by comparing patients who received radiotherapy for left-sided breast cancer, patients who received radiotherapy for right-sided breast cancer and patients who did not receive radiotherapy. RESULTS: In 25,684 Asians or Pacific islanders, the incidence of cardiac death was higher in patients who did not receive radiotherapy than in patients who received radiotherapy. Among patients who received external beam irradiation, the incidence of cardiac death was 2.00% for patients with left-sided breast cancer and 1.69% for patients with right-sided breast cancer, with no significant difference (chi-square test, p=0.427). In the period from 2000 to 2008, there was no significant difference between the cumulative heart-related death rates in patients who received radiotherapy and in patients who did not receive radiotherapy (Tarone-Ware test, p=0.406); however, in 2009-2015, the cumulative heart-related death rate in patients who did not receive radiotherapy was significantly higher than that in patients who received radiotherapy (log-rank test, p<0.001). CONCLUSION: Heart-related death after treatment for breast cancer is relatively rare in Asians or Pacific islanders. Since at least 2000, the cardiac impact of postoperative radiotherapy has not been significant.

Recurrence of Lymph Node Micrometastases After Radiotherapy for Head and Neck Carcinoma: A Propensity Score-matched Study.

Background: The standard irradiation dose to the elective lymph node area (ELNA) in locally patients with advanced head and neck squamous cell carcinoma (LA-HNSCC) to control lymph node micrometastases (LN-MM) has not changed since it was empirically determined in the 1950s. We investigated the optimal irradiation dose for controlling LN-MM in ELNAs. Patients and Methods: The pattern of recurrence of LA-HNSCC was retrospectively evaluated in patients who underwent concurrent chemoradiotherapy with cisplatin or radiation therapy alone. Results: In total, 162 patients were enrolled. The median observation period was 34 months. No recurrence was found in ELNAs. After propensity score matching, a cisplatin dose of ≥200 mg/m 2 yielded a significantly higher overall survival rate (p≤0.001) and locoregional control rate (p=0.034) than did a dose of <100 mg/m 2 . Conclusion: CCRT with a cisplatin dose of ≥200 mg/m 2 can reduce the irradiation dose to 40-44 Gy at 2 Gy per fraction to control LN-MM.