Perianal and perineal keratoacanthoma: Two cases demonstrating histologic similarity to subungual keratoacanthoma
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Updated: Jan 24, 2026

Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse POP Quantification System
Published on: September 20, 2018
Nathan Paulson1, Joanna Gibson1, Earl Glusac1,2
1Department of Pathology, Yale School of Medicine, New Haven, Connecticut.
Abstract:
Perianal keratoacanthomas are rare, with 10 cases reported to date. Perineal keratoacanthoma has not previously been described. In this report, we describe two cases of keratoacanthoma, one perianal and one perineal. Both lesions show prominent dyskeratotic keratinocytes, with striking and curious histologic resemblance to subungual keratoacanthoma.
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