Long-term toxicity and quality of life up to 10 years after low-dose rate brachytherapy for prostate cancer

Objective: To report on the long-term toxicity outcome for patients with prostate cancer treated by low-dose rate (LDR) brachytherapy (BXT).

Patients and methods: The study population comprised a cohort of men treated in our centre between March 1999 and April 2004 with LDR BXT for prostate cancer who had at least 5 years of follow-up post-implant. Patients who had died or experienced biochemical failure were excluded. We contacted eligible patients and asked them to complete a questionnaire to assess current urinary, erectile and bowel function. Urinary and erectile function was compared pre- and post-treatment and outcomes were assessed by treatment modality.

Results: Of the 226 LDR BXT-treated patients with >5 years of follow-up, 174 (77.0%) responded to the questionnaire. The mean International Prostate Symptom Score (IPSS) increased from 6.70 pre-BXT to 7.91 at follow-up (P = 0.003). Of the patients with mild symptoms pre-BXT (IPSS, 0-7), 64.2% retained mild symptoms at follow-up, 31.2% developed moderate symptoms (IPSS, 8-9) and 4.6% reported severe symptoms (IPSS, 20-35). A good or acceptable quality of life (QoL) secondary to urinary symptoms (IPSS QoL, 0-4) was reported by 98.0% of respondents. Of those patients potent (International Index of Erectile Function-5 ≥11) pre-BXT, 62.9% remained potent at follow-up. There were no differences in the proportion of patients who were potent when analyzed by the number of years post-implant. At follow-up, 51.7% and 45.4% of patients, respectively, had normal or mild bowel symptoms as indicated by the European Organisation for the Research and Treatment of Cancer questionnaire (QLQ-C30/PR25 scores, 4-8). Moderate bowel symptoms (QLQ-C30/PR25 scores, 9-12) were reported by 2.9% of respondents; none reported severe symptoms.

Conclusion: The present study shows low morbidity after LDR BXT over the long-term for a large cohort of patients.