Long term patient reported urinary function following external beam radiotherapy for prostate cancer

Introduction This study reports long-term patient reported urinary function and urinary-related quality of life (uQoL) after external beam radiotherapy (EBRT) for localized prostate cancer. Methods 574 men underwent definitive prostate EBRT to 70–78 Gy ± androgen deprivation therapy between 2000 and 2009. The median follow-up from EBRT was 44 months. Patients were evaluated at baseline (pre-EBRT) and at intervals post-treatment using the International Prostate Symptom Score (IPSS) instrument. Results Patients with mild IPSS at baseline (total 0–7) reported median total scores of 3, 4 and 3 at baseline, 6 and 48 months respectively post-EBRT. For patients with moderate IPSS at baseline (total 8–19), median total IPSS was 12 at baseline and 9 at both 6 and 48 months. For the severe IPSS group at baseline (total 20–35), the median total IPSS was 24, 12 and 14 at baseline, 6 and 48 months post-EBRT. The cumulative risk of persistent IPSS increase (greater than 5 points above baseline) at 48 months was 16%, 10% and 6% for patients with mild, moderate and severe baseline IPSS respectively. 94%, 54% and 11% of patients with mild, moderate and severe baseline IPSS reported good uQoL at baseline respectively, with these proportions increasing to 95%, 83% and 69% at 48 months. Conclusion Urinary symptoms and uQoL as measured by the IPSS instrument remained stable or improved for the majority of men after definitive EBRT with or without ADT for prostate cancer. This was especially notable for the group of men with worse baseline symptoms or uQoL, with risk of persistent worsening of urinary symptoms decreasing with higher baseline IPSS category. Understanding the expected pattern of urinary symptoms and related uQoL in the months and years following EBRT taking into account baseline urinary function is highly valuable for counselling men as part of the therapeutic decision-making process.