Abstract
A 64-years-old man with anal canal adenocarcinoma with Pagetoid spread to the perianal region is reported. He had noticed a perianal skin lesion about 8 months previously. The lesion gradually expanded; therefore, he visited our hospital. Physical examination revealed irregular erythematous plaque around his anus. Biopsy revealed intradermal large atypical foam cells suggestive of Paget's disease. Another tumor was found in the anal canal. Biopsy revealed well-differentiated adenocarcinoma. Thus, the patient was diagnosed with Paget's disease combined with anal canal adenocarcinoma, and resection of the skin tumor and anal canal polypectomy were performed. One year later, due to local recurrence and right inguinal lymph node metastasis of the anal canal cancer, the patient underwent rectal resection, regional lymph node dissection and radiation therapy. Histologically, tumor cells were found continuously infiltrating from the mucous to dermal region. The immunohistochemical stain was positive for CK20 and negative for GCDFPI5 on both lesions. These findings proved the case to have intraepidermal spread of the anal canal adenocarcinoma instead of Paget's desease. [Skin Cancer (Japan) 2005; 20: 278-281]
