Investigator
Universit De Montral
Pagetoid Squamous Intraepithelial Neoplasia of the Vulva as a Mimicker of Vulvar Extramammary Paget Disease: Two Cases with Basal Layer Sparing
Human papillomavirus-associated vulvar intraepithelial neoplasia (high-grade squamous intraepithelial neoplasia [HSIL] or VIN of usual type) is a lesion characterized by atypia extending from the basal layer to the upper epidermis. There are only rare reports of vulvar intraepithelial morphology exhibiting a pagetoid pattern of intraepithelial dissemination. We herein report two cases of vulvar HSIL in which a pagetoid pattern of spread and a largely uninvolved basal layer represented a diagnostic pitfall for extramammary Paget disease. Nuclear atypia reminiscent of HSIL in addition to expression of p16, KRT5/6, and p40 were however in favor of pagetoid HSIL. Although there is morphological and immunohistochemical overlap between these two entities, an accurate diagnosis is important, since an erroneous diagnosis of vulvar extramammary Paget disease may lead to an extensive workup comprising radiological imaging, colonoscopy, and cystoscopy.
Vulvar Cutaneous Myxoma in a Patient With Carney Complex: Avoiding Pitfalls of Myxoid Lesions of the Vulva
We present the case of a 31-year-old woman who underwent surgical excision for a polypoid, vulvar lesion. Histopathological analysis showed a diffuse myxoid stroma admixed with scant collagen fibrils. Thin-walled and branching blood vessels were prominent, with a mild perivascular lymphocytic infiltrate. Cytologically bland spindle cells with inconspicuous nucleoli were immersed in a loose myxoid stroma. This combination of histopathological features along with multinodularity in the subcutaneous fat raised concern for deep angiomyxoma, a locally destructive neoplasm. Among our differential of myxoid lesions of the vulva, we ultimately favored the diagnosis of vulvar cutaneous myxoma. Upon further investigation, we learned that our patient was indeed known for the Carney complex. We highlight that vulvar cutaneous myxomas arising in the context of the Carney complex pose a significant diagnostic challenge for pathologists and should not be overdiagnosed as aggressive lesions such as deep angiomyxoma or other malignant stromal neoplasms.
