Intensity modulated radiotherapy (IMRT) or conformational radiotherapy (3D-CRT) with conventional fractionation for prostate cancer: Is there any clinical difference?

ABSTRACT Purpose: To compare the treatment outcomes of a cohort of prostate cancer patients treated with conventional schedule using IMRT or 3DRT technique. Materials and Methods: Between 2010-2017, 485 men with localized prostate cancer were treated with conventional radiotherapy schedule with a total dose ≥74Gy using IMRT (231) or 3DCRT (254). Late gastrointestinal (GI) and genitourinary (GU) toxicity were retrospectively evaluated according to modified RTOG criteria. The biochemical control was defined by the Phoenix criteria (nadir + 2ng/mL). The comparison between the groups included biochemical recurrence free survival (bRFS), overall survival (OS) and late toxicity. Results: With a median follow-up of 51 months (IMRT=49 and 3DRT=51 months), the maximal late GU for >=grade- 2 during the entire period of follow-up was 13.1% in the IMRT and 15.4% in the 3DRT (p=0.85). The maximal late GI ≥ grade- 2 in the IMRT was 10% and in the 3DRT 24% (p=0.0001). The 5-year bRFS for all risk groups with IMRT and 3D-CRT was 87.5% vs. 87.2% (p=0.415). Considering the risk-groups no significant difference for low-, intermediate- and high-risk groups between IMRT (low-95.3%, intermediate-86.2% and high-73%) and 3D-CRT (low-96.4%, intermediate-88.2% and high-76.6%, p=0.448) was observed. No significant differences for OS and DMFS were observed comparing treatment groups. Conclusion: IMRT reduces significantly the risk of late GI severe complication compared with 3D-CRT using conventional fractionation with a total dose ≥74Gy without any differences for bRFS and OS.

Efeitos da suplementação oral com L-arginina e L-glutamina sobre a próstata ventral de ratos submetidos à irradiação / Effects of oral supplementation with L-arginine and L-glutamine on the ventral prostate of rats subjected to irradiation

O objetivo deste trabalho foi verificar o possível efeito protetor da L-glutamina e da L-arginina sobre a próstata ventral de ratos quando administradas por gavagem. Procurou-se simular as condições clinicas de pacientes submetidos à radioterapia pélvica tendo como órgão alvo outro órgão pélvico que não a próstata. Foram analisados os efeitos desta irradiação sobre a próstata considerando este órgão como normal. Foram utilizados ratos Wistar divididos em quatro grupos: Controle, animais não submetidos à irradiação (n=10); Irradiado, submetidos à irradiação abdominal e sem suplementação adicional de aminoácido por 21 dias (n=10); Irradiado + L-glutamina, submetidos à irradiação abdominal e com suplementação adicional de L-glutamina por 21 dias (n=10); e Irradiado + L-arginina, submetidos à irradiação abdominal e com suplementação adicional de L-arginina por 21 dias (n=9). Os grupos foram mantidos em condições padrão de laboratório durante todas as etapas do experimento. Os animais submetidos à irradiação abdominal receberam uma dose única de 1000 cGy no dia 8 da experimentação. A L-glutamina e a L-arginina foram dissolvidas em água destilada e administrada por gavagem através da agulha IC-810®. As próstatas foram removidas e processadas para inclusão em parafina. Foram estudados os seguintes parâmetros: estrutura acinar (área dos ácinos e altura do epitélio) e colágeno analisados por métodos morfométricos e peso corporal. O ganho de peso nos grupos suplementados foi significativamente maior se comparado ao grupo irradiado. Houve redução da altura do epitélio no grupo irradiado quando comparado ao controle. A altura do epitélio no grupo suplementado com L-arginina foi significativamente maior do que nos grupos irradiado e suplementado com L-glutamina. Houve diminuição, de aproximadamente 18%, da área dos ácinos no grupo suplementado com L-glutamina. Já no grupo suplementado com L-arginina o valor foi similar ao do controle. O efeito da L-glutamina...

The aim of this study was to investigate the possible protective effect of L-glutamine and L-arginine on the rat ventral prostate when administered by gavage. We tried to simulate the clinical conditions of patients undergoing pelvic radiotherapy as with other pelvic organ target organ than the prostate. We analyzed the effects of irradiation on prostate considering this organ as normal. Wistar rats were divided into four groups: Control, animals not exposed to irradiation (n=10); Irradiated, submitted to abdominal irradiation and without additional amino acid supplementation (n=10); Irradiated + L-glutamine, submitted abdominal irradiation and additional supplementation with L-glutamine for 21 days (n=10), and Irradiated + L-arginine, underwent abdominal irradiation and additional supplementation with L-arginine for 21 days (n=9). The groups were kept under standard laboratory conditions during all stages of the experiment. The animals underwent abdominal irradiation received a single dose of 1000 cGy in eight days of trial. L-glutamine and L-arginine were dissolved in distilled water and administered by gavage needle through the IC-810®. The prostates were removed and processed for paraffin embedding. We studied the following parameters: acinar structure (area of acini and epithelial height) and collagen analyzed by morphometric methods and body weight. Weight gain in the supplemented groups was significantly higher compared to the irradiated group. There was a reduction in epithelial height in the irradiated group compared to control. The height of the epithelium in the group supplemented with L-arginine was significantly higher than in irradiated and supplemented with L-glutamine. There was a decrease of approximately 18% of the area of the lobes in the group supplemented with L-glutamine. In the group supplemented with L-arginine was similar to the value of control. The effect of L-glutamine on the prostatic parenchyma was to keep the collagen...

Atualizaçäo: complicaçöes actínicas do sistema genital e urinário / Atualization: actinics complications of genitourinary system

A radioterapia é empregada em várias neoplasias malignas pélvicas. Näo infreqüentemente, verifica-se complicaçöes actínicas em vários órgäos dos sistemas genital e urinário com intensidade variável. Nos casos mais graves, os pacientes mesmo com câncer controlado podem ter comprometidas de maneira significativa sua qualidade de vida e suas funçöes sexuais e reprodutivas. O risco da ocorrência de um segundo tumor primário, radioinduzido, deve ser lembrado. Os autores discutem de maneira individualizada essas complicaçöes, enfatizando aspectos de seu tratamento.