Giorgia Peverelli1, Paolo Grassi1. 1. Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
Abstract
PURPOSE: Pure small cell neuroendocrine carcinoma of the prostate is a rare entity characterized by a poor prognosis due to early metastatic spread as well as resistance to treatment. Considering its increasing occurrence, clinicians should be aware of its aggressive behavior, the relevance of an early diagnosis, and proper management. METHODS: A 71-year-old man treated with brachytherapy for localized low-risk prostate cancer developed widespread disease 7 years later with a prostate-specific antigen-negative neuroendocrine small cell phenotype. He was also diagnosed with syndrome of inappropriate antidiuretic hormone secretion (SIADH) soon after starting chemotherapy. RESULTS: A substantial radiologic and clinical response to chemotherapy was observed and the paraneoplastic SIADH was successfully treated with oral vaptan therapy. CONCLUSIONS: Secondary small cell prostate carcinoma is an underestimated entity with high sensitivity to chemotherapy, although a standard treatment has not yet been defined. Moreover, oral vaptans demonstrated prompt efficacy and simple management in correcting SIADH-related hyponatremia.
PURPOSE: Pure small cell neuroendocrine carcinoma of the prostate is a rare entity characterized by a poor prognosis due to early metastatic spread as well as resistance to treatment. Considering its increasing occurrence, clinicians should be aware of its aggressive behavior, the relevance of an early diagnosis, and proper management. METHODS: A 71-year-old man treated with brachytherapy for localized low-risk prostate cancer developed widespread disease 7 years later with a prostate-specific antigen-negative neuroendocrine small cell phenotype. He was also diagnosed with syndrome of inappropriate antidiuretic hormone secretion (SIADH) soon after starting chemotherapy. RESULTS: A substantial radiologic and clinical response to chemotherapy was observed and the paraneoplastic SIADH was successfully treated with oral vaptan therapy. CONCLUSIONS: Secondary small cell prostate carcinoma is an underestimated entity with high sensitivity to chemotherapy, although a standard treatment has not yet been defined. Moreover, oral vaptans demonstrated prompt efficacy and simple management in correcting SIADH-related hyponatremia.
Authors: Eva Van Bos; Peter Dekuyper; Charlotte Gabriel; Marjan Waterloos; Anthony Van Baelen; Stefan Huybrechts; Filip Ameye; Antoon Lambrecht; Christof Vulsteke; Charlotte Soenens Journal: J Med Case Rep Date: 2020-10-28