Cytologic findings in lichen sclerosus

To describe the findings in gynecologic smears from 29 patients with biopsy-proven vulvar, vaginal or perineal lichen sclerosus.

The computerized database of the surgical pathology division of the Hospital of the University of Pennsylvania was searched for the diagnosis of lichen sclerosus from the years 1989-1992. Once these patients were identified, a search for all associated gynecologic material, including cytologic smears, biopsies and resections, was conducted. All the corresponding slides were obtained from the files and reviewed.

Parakeratosis was present in smears from 14 patients (48%) and hyperkeratosis in 18 (62%). Small parabasal cells with an elongated configuration were identified in smears from 17 patients (59%), and squamous atypia was noted in 12 (41%) of them. Following comparison with the biopsy material, the small parabasal cells appeared morphologically similar to the disorganized squamous cells that have been observed in histologic preparations. Frank dysplasia was identified in only one smear, from a patient with lichen sclerosus who had had a previously resected vulvar carcinoma; the vulvar biopsy disclosed carcinoma in situ.

Parakeratosis, hyperkeratosis and small, elongated parabasal cells are common features in gynecologic smears from patients with lichen sclerosus. Focal squamous atypia may also be present but is not necessarily reflective of a preneoplastic process. The presence of these four features in routine gynecologic smears should prompt a correlation with the clinical and histologic diagnoses.