Treatment outcomes and comparative survival analysis of intraductal carcinoma of the prostate.

Purpose: Intraductal carcinoma of the prostate is a rare subset of prostate cancer, for which no consensus treatment guidelines exist. We seek to investigate treatment and survival outcomes for IDC-P in the context of current NCCN guidelines.

Methods: The Surveillance, Epidemiology, and End Results (SEER) database was queried to identify patients with intraductal carcinoma of the prostate diagnosed between 2000 and 2020. Cox regression analysis and log-rank comparisons of both overall and cause-specific survival over 5- and 10-year timeframes were conducted.

Results: 945 patients were identified. Cox regression analysis demonstrated treatment with unimodal surgery (hazard ratio (HR) = 3.70, p = 0.005) was associated with decreased 10-year cause-specific survival, while unimodal treatment with radiotherapy was associated with decreased 5- and 10-year overall survival (HR = 2.14, p = 0.025; HR = 2.16, p = 0.005, respectively). Univariate survival subanalysis of treatment regimens demonstrated decreased 5-year cause-specific (p = 0.004) and overall (p = 0.019) survival among patients that received only radiotherapy as treatment. Radical prostatectomy alone was non-inferior to radical prostatectomy with adjuvant radiotherapy in the context of 10-year overall survival (90% vs 80%; p = 0.58).

Conclusion: Differences in both 5- and 10-year overall survival and cause-specific survival were present among patients diagnosed with IDC-P. Treatment with unimodal radiotherapy among patients with IDC-P was associated with decreased survival compared to treatment with radical prostatectomy ± adjuvant radiotherapy, while radical prostatectomy alone was non-inferior to radical prostatectomy with adjuvant radiotherapy. Further research into the risk stratification and optimal treatment of these patients is warranted.