HDR Mono-Brachytherapy for low and intermediate risk cancer of the Prostate

Introduction

Based on recent data of low α/β for prostate cancer cells and ultrasound guided real time dosimetry we started with HDR mono-brachytherapy 2004. The stepping source technology gives a highly conformal and intensity-modulated dose with respect to the target (within the prostate capsule) and organs at risk (the urethra and the rectum).
First schedule used (2004-2005) was one implant with 4 fractions of 9,5 Gy over 2 days. We found some logistic problems with that schedule (patient tolerance, nursing issues and to have full control of implant geometry and dosimetry between the fractions). From 2005 to present time we use three (11 Gy x 3) or two (14 Gy x 2)  separate implants and fractions with two weeks interval.
EQD2 (α/β=3) are similar for the 3 fractionation schedules (95, 92, and 95 Gy respectively).

Material and methods

Each column gives pretreatment characteristics for each schedule used. Mean numbers and range are given. Pre volume is the volume given by the refering urologist. PSA value is in µg/l (normal≤3µg/l)

Results

Results, toxicity (median grades at last follow-up)
Urinary (dysuria, frequency, urgency, flow resistance) and Rectal symptoms:  0= no symptoms, 1= some symptoms, 2= more symptoms medication needed sometimes
Erectile and Sexual functions: 0= no function, 1= impaired function, medication sometimes, 2= normal

Conclusions

• HDR mono-brachytherapy seems to give a promi-
 sing PSA regression in low and early intermediate
 Prostate Cancer.
• Long time toxicity is low, affecting urethra and
  some impaired erectile and sexual functions.
• Results are similar to other groups
 (Martinez A et al Am. J. Clin.Onc. 2009).
 More follow up time is required.