Long-term follow-up of International Prostate Symptom Score (IPSS) in men following prostate brachytherapy

Objective To investigate variation in the International Prostate Symptom Score (IPSS) in men following prostate brachytherapy. Methods From January 2004 to November 2009, 524 consecutive patients underwent prostate brachytherapy either alone or in combination with external beam radiation therapy for T1c–T3b prostate cancer. The IPSS was assessed preimplant and at 1, 6, 12, 24, 36, and 48 months after treatment. Clinical and treatment-related factors were assessed for correlations with the IPSS increase. Results The mean preimplant IPSS was 7.4, with the greatest mean score of 16.0 at 1 month. At 6 months, the mean total IPSS had decreased to 11.5, but it was still statistically significantly greater than that at baseline (<0.001). At 12 months, the IPSS was decreased to 8.6, slightly greater than baseline ( p = 0.001). The IPSS of 45.4 % (69/152) patients gradually returned to preimplant levels and that of 71.1 % (108/152) patients returned to within 3 points of the baseline at 24 months. At 24, 36, and 48 months after seed implantation, the IPSS was 8.6, 7.7, and 8.2, respectively, and none of these values differed statistically significantly from baseline ( p > 0.05). Sixteen patients (3.1 %) showed AUR, and 11 patients required catheterization. On univariate and multivariate analyses, the IPSS increase was best predicted by lower preimplant IPSS. Conclusion In our series, IPSS after prostate brachytherapy peaked at 1 month and gradually returned to approximately baseline at 24 months. The IPSS increase was best predicted by lower preimplant IPSS.