Case 1 : A 76-year-old man consulted a physician because of pollakisuria, decline of urinary stream. A high level of serum
prostate specific antigen (PSA) was detected and he came to our hospital. He was diagnosed to have
prostate cancer, cT3aN0M1b, and was treated with combined
androgen blockage (CAB). Two years and nine months later, postrenal failure appeared and serum level of
neuron-specific enolase (NSE) was 162 ng/ml. We performed re-biopsy of prostate, and pathological examination indicated
small cell carcinoma of the prostate. We treated him with
combination chemotherapy comprised of
etoposide and
carboplatin, which was effective. Serum level of NSE was decreased and computed tomography showed reduction of the prostate volume and
metastasis. Case 2 : An 84-year-old man was treated at a hospital with
radiation therapy and CAB, because of
prostate cancer. He came to our hospital with bladder tamponade. We performed transurethral coagulation and transurethral biopsy. Pathologically it proved to be
small cell carcinoma of the prostate. The stage was cT4N1M1a, NSE and
pro-gastrin-releasing
peptide (Pro-GRP) levels were high. The same treatment given to him as in case 1, effectively decreased the
metastasis and the level of serum NSE.