2022 Volume 55 Issue 9 Pages 591-599
An 84-year-old woman presented with perianal skin redness. Histopathological examination of skin biopsy revealed Paget’s cells, and colonoscopy indicated rectal cancer. Thus, pagetoid spread of rectal cancer was diagnosed. Robot-assisted abdominoperineal resection of the perineal skin lesion was performed. A further histopathological examination revealed that Paget’s cells were not contiguous with rectal cancer cells, and anal gland adenocarcinoma was thus identified. The immunohistochemical staining pattern of the pagetoid spread (CK20+/CK7+) was consistent with that of the anal gland adenocarcinoma (CK20+/CK7+), rather than with the rectal cancer (CK20+/CK7–). Therefore, we ultimately diagnosed pagetoid spread of anal gland adenocarcinoma. Anal gland adenocarcinoma is rare and difficult to detect in the early stage because the lesion is not exposed on the mucosal surface. Since anal gland adenocarcinoma was latent in the present case, a detailed immunohistopathological examination was necessary to diagnose the origin of the perineal Pagetoid spread accurately.
