[A case of porocarcinoma arising on the penile shaft]

Porocarcinoma is a rare eccrine sweat gland tumor, and a varied treatment is not yet determined for metastatic disease because of the chemo-resistant and radio-resistant nature of this tumor.

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 surgery for the treatment of residual lymph nodes in the paraaortic area. Abdominal CT scan revealed partial response, about -94% shrinkage, after one course of chemotherapy. The duration of the response lasted four 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.

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 rare tumor suggested that this new regimen might be effective against porocarcinoma.