Hypofractionated radiotherapy recommendations for localized prostate cancer in Brasil.

OBJECTIVE: Several prospective randomized trials have shown that hypofractionation has the same efficacy and safety as the conventional fractionation in the treatment of localized prostate cancer. There are many benefits of hypofractionation, including a more convenient schedule for the patients and better use of resources, which is especially important in low- and middle-income countries like Brasil. Based on these data, the Brazilian Society of Radiotherapy (Sociedade Brasileira de Radioterapia) organized this consensus to guide and support the use of hypofractionated radiotherapy for localized prostate cancer in Brasil. METHODS: The relevant literature regarding moderate hypofractionation (mHypo) and ultra-hypofractionation (uHypo) was reviewed and discussed by a group of experts from public and private centers of different parts of Brasil. Several key questions concerning clinical indications, outcomes and technological requirements for hypofractionation were discussed and voted. For each question, consensus was reached if there was an agreement of at least 75% of the panel members. RESULTS: The recommendations are described in this article. CONCLUSION: This initiative will assist Brazilian radiation oncologists and medical physicists to safely treat localized prostate cancer patients with hypofractionation.

Hypofractionated radiotherapy recommendations for localized prostate cancer in Brasil

SUMMARY OBJECTIVE: Several prospective randomized trials have shown that hypofractionation has the same efficacy and safety as the conventional fractionation in the treatment of localized prostate cancer. There are many benefits of hypofractionation, including a more convenient schedule for the patients and better use of resources, which is especially important in low- and middle-income countries like Brasil. Based on these data, the Brazilian Society of Radiotherapy (Sociedade Brasileira de Radioterapia) organized this consensus to guide and support the use of hypofractionated radiotherapy for localized prostate cancer in Brasil. METHODS: The relevant literature regarding moderate hypofractionation (mHypo) and ultra-hypofractionation (uHypo) was reviewed and discussed by a group of experts from public and private centers of different parts of Brasil. Several key questions concerning clinical indications, outcomes and technological requirements for hypofractionation were discussed and voted. For each question, consensus was reached if there was an agreement of at least 75% of the panel members. RESULTS: The recommendations are described in this article. CONCLUSION: This initiative will assist Brazilian radiation oncologists and medical physicists to safely treat localized prostate cancer patients with hypofractionation.

Analysis of the Abscopal Effect With Anti-PD1 Therapy in Patients With Metastatic Solid Tumors.

Abscopal effect is a rare phenomenon characterized by tumor regression of untreated metastatic lesions after a local therapy (eg, radiotherapy). We studied the probability of abscopal effect with radiotherapy associated with anti-programmed death cell 1 (PD1) therapy after progression on anti-PD1. This study is a retrospective analysis of patients treated with nivolumab or pembrolizumab for melanoma, non-small cell lung cancer (NSCLC) and renal cancer at Antônio Ermírio de Moraes Oncology Center, Brazil. To be eligible for this analysis, patients must have had unequivocal evidence of disease progression on anti-PD1 therapy and subsequent radiotherapy for any tumor site while still receiving anti-PD1. The abscopal effect was characterized as a response outside the irradiated field after radiotherapy plus anti-PD1. Sixteen patients were evaluated, including 12 metastatic melanoma, 2 metastatic NSCLC, and 2 metastatic renal cell carcinoma. The median time to disease progression on anti-PD1 was 3 months. The radiotherapy field included lung, lymph nodes, and bones, with a median total dose of 24 Gy (1-40 Gy), usually in 3 fractions (1-10 fractions). Three patients with melanoma developed an abscopal effect at a rate of 18.7% (25% among melanoma patients). Of note, one of them achieved a remarkable complete response lasting >6 months. Three patients with melanoma obtained a significant local response after radiotherapy, despite no response in distant metastases. Eleven patients presented disease progression after radiotherapy. No increased toxicity was observed. In conclusion, no patients with NSCLC or renal cancer showed abscopal effect, but 25% of patients with melanoma showed regression of nonirradiated lesions when anti-PD1 was continued after radiation to a tumor site that had progressed on anti-PD1 monotherapy.