陰茎体部に発生した汗孔癌の1例  [in Japanese] A CASE OF POROCARCINOMA ARISING ON THE PENILE SHAFT  [in Japanese]

83歳男性,手拳大,カリラワー状の陰茎体部腫瘤を主訴に当科を受診した。亀頭部,冠状溝には異常を認めず,CT検査では両側鼠径部,骨盤内から傍大動脈節に至る広範囲のリンパ節腫大を認めた。腫瘍からの動脈性出血を繰返した為,全除精術と両側の腸骨鼠径部リンパ節郭清術を施行した。腫瘍は髄様で胞体の乏しい均一な細胞集団より構成され,角化傾向や棚状配列は見られず,一部では腺管様構造も観察された。免疫組織染色ではCEA(+),S-100(-)であり,皮膚付属器であるエクリン汗器官由来の汗孔癌と診断された。術後残存する傍大動脈リンパ節転移に対してメソトレキセート,シスプラチン,ブレオマイシン,アドリアマイシンの4剤による化学療法を1クール施行し,-94%の腫瘍縮小効果が得られた。4ヵ月後,MRSA肺炎による呼吸不全の為死亡した。陰茎体部に発生した汗孔癌はまれで,転移を有する症例に対する治療法は未だに定まっていない。本症例は高齢者であるため,1クールしか化学療法が施行できなかったが著明な腫瘍縮小効果が得られ転移を有する汗孔癌に対する治療法として有用である可能性が示唆された。

(Background) Porocarcinoma is a rare eccrine sweat gland tumor, and a valied treatment is not yet determined for metastatic disease because of the chemo-resistant and radio-resistant nature of this tumor. (Case) This report describes a case of porocarcinoma arising on the penile shaft of 83-year-old man with extensive lymph node metastases. He was treated with emasculation and bilateral ilio-inguinal lymph node dissection. Histological examination of the resected tumor showed a homogeneous round cells with duct-like formation in some part and Pagetoid infiltration was also noted in the dermis. Immunohistochemical examination demonstrated a positive CEA and negative S-100 staining and this result was consistent with the pathological diagnosis of porocarcinoma. One course of chemotherapy which consisted of methotrexate, cisplatin, adriamycin, and bleomycin was given to the patient following the surgery for the treatment of residual lymph nodes in the paraaortic area. Abdominal CT scan revealed partial response, about -94% shirnkage, after one course of chemotherapy. The duration of the response lasted for 4 months. He died of pneumonia caused by MRSA after 4 months and the autopsy revealed multiple liver metastases and a massive infiltration of tumor cells in the bone marrow of lumbar vertebra. (Conclusions) There is no definite treatment modality available for metastatic porocarcinoma. Because of the patient's age, only one course of chemotherapy was given, however, a fairly good response against this rate tumor suggested that this new regimen might be effective against porocarcinoma.