Paget disease is an intraepithelial neoplastic proliferation, commonly occurring in the breast and apocrine-rich areas, often associated with an underlying internal malignancy. Extramammary Paget disease (EMPD) of the oral cavity is exceedingly rare, with only eight reported cases, four of which were associated with an underlying internal malignancy. Here, we report a case of oral EMPD involving the buccal mucosa and gingiva of an 81-year-old male with no known underlying internal malignancy. The Paget cells were positive for CK7, CK20, CAM5.2, and androgen receptor, but negative for SOX10 and p63. The immunophenotype, association with internal malignancies, and treatment approaches for oral EMPD are reviewed.

Extramammary Paget disease (EPMD) of the oral mucosa is an unusual and extremely rare condition, with fewer than ten cases documented. Here, we report a case of EMPD extensively involving oral mucosa and underlying salivary ducts in a 72-year-old male and review published clinical, histologic, immunophenotypic, and prognostic features of this rare entity.