Urethral and bladder dosimetry of total and focal salvage Iodine-125 prostate brachytherapy: Late toxicity and dose constraints

FS I-125 BT reduces urethral and bladder dose significantly compared to TS. With TS, there is an increased risk of cumulative dose and severe GU toxicity. Based on these findings, bladder D2 cc should be below 70 Gy and urethral V100 below 0.40 cc.