Rare desmoplastic trichilemmoma associated with sebaceous nevus

Abstract

Nevus sebaceous of Jadassohn is a congenital hamartoma that usually affects the scalp and face. Several benign or malignant neoplasias may develop in the lesion and the most common are trichoblastoma, syringocystadenoma papilliferum, and basal cell carcinoma. Trichilemmoma is a benign solid tumor originating from external sheath cells of pilosebaceous follicles. When it is characterized by a central zone of desmoplasia, it is called desmoplastic trichilemmoma. We report a case of a 58-year-old patient who developed a tumor in a sebaceous nevus. We performed a total excision of the lesion. Histopathological diagnosis was compatible with desmoplastic trichilemmoma. Our literature review reveals that the occurrence of trichilemmoma desmoplastic is unusual. Moreover, it can mimic an invasive carcinoma on histological and clinical examinations. This fact confirms the importance of reporting the occurrence of this rare cancer in a nevus sebaceous of Jadassohn.

Desmoplastic trichilemmoma of the scalp: case report and literature review of immunohistochemical staining features

“…The proportion of desmoplasia varies, but is generally between 20% and 60% of the lesion. 9 Although 10 cases have been reported in which DT developed on the scalp, 5–8 the patient in our case had some unique clinical features: (1) the lesion was 1.5 cm in diameter, larger than the typical size of 1 cm; and (2) the lesion showed different histological characteristics, with less glycogen in the cytoplasm, as well as tumor cells with PAS-negative staining that were only focally positive for CD34. These findings differed from those in previous reports.…”

“…Thus far, only 10 cases have been reported in which DT affected the scalp. [5][6][7][8] In the present report, we describe a man who exhibited DT of the scalp; we also summarize immunohistochemical features from previous reports of DT, which may aid in differential diagnosis of this disease.…”