Comparison of Contemporary Treatment Options for Early Prostate Cancer: A Single Institution Series

Purpose: To evaluate outcomes of low-risk prostate cancer patients managed with competing treatments, in a single institution. Methods: Patients with low-risk cancer (cT1-T2a and Gleason score 6 and PSA<10ng/ml) from 2006-2008 were included. Treatment details and worst late toxicities (Common Terminology Criteria for Adverse Events version 3.0) were retrieved through retrospective chart review. Biochemical relapse-free survival following primary (pbRFS) and salvage treatments (sbRFS), metastasis-free (MFS), cause-specific (CSS) and overall survival (OS) were also evaluated. Results: In 582 patients, treatment options were active surveillance (AS, N=181), radical prostatectomy (RP, N=59), external beam radiation (EBRT, N=66; 76 Gy in 38 fractions), low-dose rate brachytherapy (LDR, N=192), stereotactic ablative radiotherapy (SABR, N=84; 35Gy in 5, weekly fractions). Median follow-up was 72.8 months. Six-year pbRFS and sbRFS were 94.0% and 95.8%, 84.1% and 98.3%, 92.1% and not applicable, 94.4% and not applicable, 95.8% and 98.7%; for AS, RP, EBRT, LDR and SABR, respectively. In multivariate analysis, RP had inferior pbRFS compared to EBRT, LDR or SABR (p-value <0.05) and a trend for AS (p-value 0.15). CSS, MFS and OS were similar. Toxicities were minimal in AS cohort. EBRT patients had higher rates of dysuria (19.7%), transurethral resection of prostate (6.1%) and hematochezia (7.6%). One patient each in EBRT, LDR and SABR cohorts had grade 4 toxicity. Toxicity data was not available for RP. Conclusion: In primary setting all treatment modalities apart from RP had a 6-year pbRFS >90%, likely due to selection bias. Following salvage therapy, sbRFS was >95.0% in AS, RP and SABR cohorts.