Complete remission in a patient with metastatic mixed adenocarcinoma/extrapulmonary small cell carcinoma of the prostate

Approximately 10% of all extra-pulmonary small cell carcinoma (EPSCC) arises in the prostate either as de novo mixed adenocarcinoma with small cell components or a pure small cell carcinoma. Extensive disease carries a median survival of about 10 months in retrospective studies. We present a case managed aggressively with concomitant hormonal and chemotherapy, now 36 months without evidence of disease. At a routine physical, a 55 year male was found to have a 5 cm left upper lobe lung mass, invading his 3rd rib. An FNA revealed an adenocarcinoma of unknown primary. His PSA was elevated to 8 ng/mL and a prostate biopsy revealed Gleason 9 adenocarcinoma with neuro-endocrine/SCC components. A bone scan revealed extensive bone metastasis. He was managed aggressively with concomitant cisplatin, etoposide and hormonal therapy and received 73 Gy of radiation to the prostate. PET scans demonstrated marked response to chemotherapy. PSA and chromogrannin levels down trended to normal limits. His most recent PET scan in July 2010 revealed no evidence of disease and is in remission. We present a unique case of metastatic mixed adenocarcinoma/SCC of the prostate, in which the patient survived more than 36 months with complete remission after initiation of aggressive hormonal and chemotherapy. Data on survival in this patient population is limited to case reports, and ordinarily carries a poor prognosis of less than 1 year. In patients with clinical and pathologic features of mixed disease, initiation of early multi-modal therapy is warranted. Additionally, it may be of prognostic significance to biopsy any metastatic lesion.