Whole Pelvic Radiation Therapy Versus Prostate Only in Patients With Intermediate-, High-, and Very High-Risk Prostate Cancer According NCCN Criteria Treated With Radical Intention: Recap Data Base

Abstract

rectal dose and serving as a fiducial marker in patients undergoing radiation therapy for prostate cancer. Materials/Methods: Biodegradable balloon was inserted transperineally, between the anterior rectum and the prostate, through guidance of transrectal ultrasound. Following insertion, the balloon was inflated with sterile physiological solution and sealed. The procedure was performed under mild sedation and in an outpatient clinic. A week later the patients underwent CT simulation and three weeks later they started the radiation course. The radiation protocol consisted of 2.5 Gy once a day, 5 times a week for 28 fractions, to a total dose of 70 Gy in 5 pts. The treatment was delivered through volumetric modulated arc therapy and accuracy was evaluated through cone beam CT (CBCT). Results: Six patients, so far, underwent implantation. Their characteristics include mean age 71 years (range, 61-79 years), PSA 9.3 (range, 5.9-17.3), Gleason score 3+3 in 5 pts and 4+3 in one, and stage T1c (5 pts) and T2 (1 pt). The dimension of the balloon were 4 x 2 x 1.5 cm (CC, lateral and AP). One patient developed urinary retention (the urine catheter was removed a day later) and another had mild bleeding (spontaneously stopped, stable parameters). Following treatment planning the mean V70 of the rectum was 0 (range, 0-0.3) V60 7.1 (range, 2-16) and the V50 was 23 (range, 9-39). The V60 of the bladder was 21 (range, 6-41). The balloon was demonstrated in the CBCT reconstruction and served as a reference point for daily radiation delivery. No immediate side effects were noted during the treatment course. Along a mean F/U of 8 months (range, 6-10 months) 1 out of 6 pts developed grade 1 rectal toxicity and urinary toxicity. No other complications were noted. Conclusions: The biodegradable perineal balloon has a good safety profile, and is efficient in reducing the dose to the rectal wall and in serving as a fiducial marker. Higher daily radiation dose and possible injection of contrast material into the balloon are currently being considered. Author Disclosure: R. Ben-Yosef: L. Stock Options; yes. T. Heres: None. A. Berniger: None. R. Carmi: None. I. lvovich: None. Y. Genesin: None.