カルチノイド腫瘍が混在した前立腺小細胞癌

Small cell carcinoma of prostate coexisting with carcinoid：A case report

78歳，男性。前立腺肥大症の診断にて他院で経尿道的前立腺切除術（TURP）を施行され，低分化前立腺癌と診断された。内分泌療法が開始されたが，血尿による膀胱タンポナーデをきたし，当院で経尿道的凝固止血術（TUC）およびTURPを施行した。病理組織診断はカルチノイド腫瘍が混在した前立腺小細胞癌であった。放射線治療とドセタキセルの投与を行ったが，全身へ遠隔転移をきたし，診断後7か月で癌死した。

We report a rare case of small cell carcinoma（SCC）coexisting with carcinoid of prostate. A 78-year-old man with a chief complaint of dysuria and macrohematuria underwent a transurethral resection of the prostate（TURP）at another hospital. Although the prostate specific antigen was 5.2 ng/ml,histological diagnosis was poorly differentiated adenocarcinoma with a Gleason's score of 5＋4（T3aN0Mx）. After 3 months of maximum androgen blockade,he was admitted to our hospital because of urinary retension with macro-hematuria. We performed transurethral coagulation and TURP because of the repeated bladder tamponade. The immunohistochemical examination of specimens revealed both SCC and carcinoid. Abdomino-pelvic CT showed an enlarged prostate and distant metastasis. Radiotherapy resulted in a great reduction of the tumor volume,but chemotherapy（docetaxel）was ineffective. He developed multiple distant metastasis and died of disease 7 months after the diagnosis.