Small-Cell Carcinoma of the Prostate: Report of Outcomes of Localized Disease Using the National Cancer Database

Abstract

Background: Small-cell carcinoma of the prostate (SCCP) is a rare but aggressive prostate cancer histology. We studied the reported comparative outcomes of the efficacy of radiotherapy (RT) versus surgery for nonmetastatic SCCP.

Methods: The National Cancer Database (NCDB) was queried for nonmetastatic disease diagnosed from 2004 to 2015 as SCCP (defined as having a component of SCCP) receiving a single definitive local control modality (RT or surgery).

Results: A total of 243 patients were included (177 RT and 66 surgery). A total of 142 patients received chemotherapy (CHT). Mean age was 68 years. One hundred forty patients had adenocarcinoma concurrently with the SCCP while 103 patients had pure histology. For pure histology, multivariable analysis (MVA) showed nonacademic facility, stage 4 disease, and poorly differentiated grade were associated with worse survival. On MVA, receipt of CHT (hazard ratio [HR] = 0.84, P = .644) or receipt of androgen deprivation therapy (HR = 0.88, P = .715) did not affect overall survival. Receipt of RT was nonsignificant compared to surgery (HR = 0.75, P = .475). For mixed histology, MVA showed receipt of CHT and prostate-specific antigen > 20 ng/mL were associated with worse survival. Receipt of androgen deprivation therapy (HR = 1.35, P = .414) did not affect overall survival. Receipt of RT was also nonsignificant compared to surgery (HR = 1.42, P = .344).

Conclusion: RT and surgery for nonmetastatic SCCP yield comparable options as local therapies.

Keywords: Local therapy; Overall survival; Prostate cancer; Radiation versus surgery; Small cell carcinoma.