Brachytherapy for prostate cancer: is the pretreatment prostate volume important?

To prospectively determine the effect of prostate volume on lower urinary tract symptoms (LUTS) in terms of changes in the International Prostate Symptom Score (IPSS), and to determine whether prostate volume affects the retention rate after brachytherapy, as there is concern that patients with larger prostates might develop more troublesome LUTS after brachytherapy. We prospectively identified 100 consecutive patients who had brachytherapy for prostate cancer, using a real-time three-dimensional seed implantation technique, at one institution. At each follow-up review the IPSS was recorded. To determine the effect of prostate volume on the IPSS after treatment the patients were divided into two groups according to prostate volume at brachytherapy (< 50 and >= 50 mL). The median patient age was 62 years, the overall median prostate volume was 42 mL and the median intraoperative D90 was 190 Gy. The pretreatment IPSS was 4 and 8 for the < 50 and >= 50 mL groups, respectively, and at 3 months after brachytherapy the median IPSS increased to 18 and 20 for the two groups, respectively. Eleven patients went into acute retention of urine after brachytherapy (six in the >= 50 mL group). This study shows that patients with prostates of >= 50 mL have an IPSS comparable with those who have prostates of < 50 mL. Large prostates should not be considered an exclusion criterion when an intraoperative planning technique is used for brachytherapy.