TRICHILEMMOMA: CA BỆNH KHÓ KHĂN TRONG CHẨN ĐOÁN PHÂN BIỆT GIỮA CÁC NHÓM BỆNH U TẾ BÀO SÁNG

Abstract

Objectives: To describe the clinical characteristics, Hematoxylin–eosin histopathology, and immunohistochemical findings of a case of trichilemmoma at Hanoi Dermatology Hospital, thereby providing detailed guidance for establishing a definitive diagnosis of clear cell skin tumors through correlation of clinical data, Hematoxylin–eosin histopathology, and immunohistochemistry. Subjects and Methods: Case report. A 66-year-old male patient presented with a tumor in the left parotid area for approximately 6 months. The lesion was well-demarcated, relatively symmetrical, had regular borders, pink-brown color, firm consistency, infiltrative, non-tender, non-pruritic, without erosion or ulceration, and no accompanying systemic symptoms. Histopathology showed tumor cells arranged in nests with clear cytoplasm and peripheral palisading. Immunohistochemical staining demonstrated positivity for p63 and CD34, Ki-67 positivity in 10% of cells, and negativity for BerEp4, BCl-2, CK7, and EMA. Results: The case was definitively diagnosed as trichilemmoma. Pathologists noted diagnostic challenges in differentiating this tumor from other cutaneous clear cell neoplasms. Conclusion: Recognizing the broad spectrum of clear cell skin tumors is essential for constructing and narrowing the differential diagnosis. We provide detailed guidance for definitive diagnosis of clear cell skin tumors by integrating clinical data, Hematoxylin–eosin histopathology, and immunohistochemistry.