title: Signet ring squamous cell carcinoma--the forgotten variant: case report and review of the literature.
abstract: Squamous cell carcinoma is one of the commonest skin cancers. In most instances, histological diagnosis is straightforward and does not pose any diagnostic challenge to the handling pathologist. We report a rare case of signet ring squamous cell carcinoma (SRSCC) occurring in an 84-year-old woman who presented with a sore on the upper lip. Excision of the lesion showed signet ring carcinoma within a scar and surface ulceration. Deeper sections showed focal area of squamous differentiation. Although rare, consideration of squamous cell carcinoma as a diagnosis of primary skin tumors with signet ring morphology, especially in the absence of history of adenocarcinoma, may prevent missing rare cases of SRSCCs.
authors.affiliation: Department of Pathology and Laboratory Medicine, Northern Ontario School of Medicine, William Osler Health Center, Brampton Civic Hospital, Brampton, Ontario, Canada.
authors.forename: Dina
authors.initials: D
authors.lastname: El Demellawy
authors.forename: Kazuya
authors.initials: K
authors.lastname: Onuma
authors.forename: Salem
authors.initials: S
authors.lastname: Alowami
mesh_terms: D000369:Aged, 80 and over; D018279:Carcinoma, Signet Ring Cell / Q000378:metabolism / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D012878:Skin Neoplasms / Q000378:metabolism / Q000473:pathology*