Clinical Outcomes of Neuroendocrine Prostate Cancer Treated With Platinum-Based Chemotherapy: A Single-Institution Experience.

INTRODUCTION

Neuroendocrine prostate cancer (NEPC) is aggressive with a poor prognosis. Most reported series derive from large databases (e.g., SEER) lacking granular clinical detail. We examined our institution's experience with 58 patients with NEPC.

PATIENTS: We identified patients with biopsy-proven NEPC treated with platinum-based chemotherapy. De novo versus treatment-emergent (t-NEPC) status, stage, and treatment history were recorded.

METHODS

For localized NEPC treated with definitive intent, disease-free survival (DFS) was measured from NEPC diagnosis to relapse or death; for metastatic NEPC, systemic therapies were noted. Overall survival (OS) was defined as time from NEPC diagnosis to death and estimated by Kaplan-Meier method, with log-rank comparisons.

RESULTS

Fifty-eight patients with NEPC were identified (median age, 66 years); 19 (32.8%) had de novo NEPC and the remainder had t-NEPC. Forty-four (75.9%) had metastatic disease at NEPC diagnosis. Histology was pure small cell (n = 15), neuroendocrine (n = 21), or mixed (n = 22, e.g., with adenocarcinoma). Of 14 patients without metastases at diagnosis, 10 received definitive local therapy (median DFS, 11.7 months). OS was longer for de novo versus t-NEPC disease (26.5 vs 10.9 months, P = 0.0001) and for mixed versus pure histology (21.0 vs 11.0 months, P = 0.0002). Among 45 patients with metastatic NEPC treated with first-line carboplatin and etoposide, OS did not differ with versus without maintenance immunotherapy (12.5 vs 11.0 months, P = 0.9).

CONCLUSION

In one of the largest non-database series of patients with NEPC, OS was longer for de novo disease and mixed histology. Maintenance IO after carboplatin plus etoposide was not associated with improved OS.