Etoposide plus cisplatin produces substantial but temporary regression in metastatic prostatic small cell neuroendocrine carcinomaSurgery and Chemotherapy Provide Temporary Relief for Prostate Cancer

ObjectiveTo describe the diagnostic challenges, treatment response, and potential benefits and risks of cytoreductive surgery in de novo metastatic prostatic small cell neuroendocrine carcinoma (SCNEC).MethodsWe retrospectively reviewed the clinical course of one patient with de novo metastatic prostatic SCNEC.ResultsA 50-year-old man presented in June 2022 with progressive dysuria for more than 1 year and acute urinary retention for 1 day. Transurethral resection of the prostate (TURP) was performed to relieve obstruction, and review of the specimen supported SCNEC. Staging 18F-FDG PET/CT showed an FDG-avid prostate, multiple lymph nodes, and bilateral non-FDG-avid pulmonary nodules without a dominant pulmonary primary; a prostatic primary with clinically suspected pulmonary metastases was favored, although the lung lesions were not biopsied. Seven cycles of etoposide plus cisplatin (EP) produced marked local regression, including a reduction in prostate volume from 72 to 17 cm³, but residual tumor persisted and a RECIST response category could not be assigned retrospectively. Cytoreductive laparoscopic radical prostatectomy was performed in February 2023. Postoperative pathology showed a mixed neuroendocrine–non-neuroendocrine neoplasm (MiNEN). A vesicourethral anastomotic leak improved conservatively, and urinary obstruction improved for approximately 3 months. Disease progressed in July 2023, and irinotecan plus carboplatin provided no durable clinical disease control. The patient died in December 2023, approximately 18 months after diagnosis.ConclusionEP can produce substantial but temporary regression in metastatic prostatic SCNEC. This case did not establish a survival benefit from surgery, although temporary relief of urinary obstruction was reported. Systemic therapy should remain the priority, and surgery should be limited to carefully selected local-control or palliative indications.