RESUMO
PURPOSE: The primary endpoint was to assess the late toxicity of a hypofractionated radiotherapy schedule in relation to radiation parameters concerning the rectum and bladder. The second endpoint was to assess a composite of biochemical and clinical failure. METHODS: Sixty-four prospectively selected patients diagnosed with localized low risk prostate cancer, Gleason score (GS) <7, PSA <10, and T1-2N0, were treated with external 3- dimensional conformal radiotherapy (3D-CRT). Patients received 57.75 Gy in 21 daily fractions of 2.75 Gy/fraction. RESULTS: Late gastrointestinal (GI) toxicity was as follows: grade 0: 47 (73.4 %) patients, grade 1: 12 (19.2 %), grade 2: 4 (6.3%), and grade 3: 1 (1.6%). There was a significant correlation between D50, V70 and EORTC/RTOG late rectal toxicity score (p<0.001 and p=0.006, respectively). Grade 1 and 2 late bladder toxicity was seen in 4.7 and 1.6% of the patients, respectively. With a median follow up of 18 months no biochemical relapse was observed. CONCLUSION: The present study supports the use of hypofractionated radiation therapy which showed a high therapeutic ratio with acceptable toxicity and no biochemical relapse during follow-up.
