Desmoplastic trichoepithelioma on the face mimicking basal cell carcinoma: a case report and literature review

Isabele M. Saldanha, Dermatology Service of the Federal University of Pará, João de Barros Barreto University Hospital, Belém, Pará, Brazil Airton K. Motizuki, Department of Medicine, Faculty of Medicine of Federal University of Pará, Belém, Pará, Brazil Renata M. Oyama-Okajima, Dermatology Service of the Federal University of Pará, João de Barros Barreto University Hospital, Belém, Pará, Brazil

Desmoplastic trichoepithelioma is a rare benign cutaneous neoplasm that differentiates toward germinative cells of the hair follicle. It can be classified as familial multiple trichoepithelioma, solitary, and desmoplastic, the latter being a rare variant with low incidence and clinical features resembling basal cell carcinoma. We report the case of a 54-year-old female patient who presented with a brownish plaque exhibiting areas of dark pigmentation, an irregular outline, a pearly sheen, and surface telangiectasias in the right paranasal region. Complementary studies, including histopathological and immunohistochemical analyses, were performed to establish the definitive diagnosis. Furthermore, this cutaneous lesion displays both clinical and histopathological characteristics that complicate differentiation between benign and malignant tumors, making immunohistochemistry essential to confirm the desmoplastic variant of trichoepithelioma.

Keywords: Desmoplastic trichoepithelioma. Differential diagnosis. Basal cell carcinoma.