Dermoscopy of Desmoplastic Trichoepithelioma Reveals Other Criteria to Distinguish It from Basal Cell Carcinoma

Abstract

Background: Desmoplastic trichoepithelioma (DT) is a rare benign adnexal neoplasm considered to have follicular differentiation. It usually presents as an asymptomatic, firm, annular plaque with a raised border. The diagnosis of DT is based on clinical and histological features which can be similar to those of morpheiform basal cell carcinoma. Taking this into consideration, the use of another diagnostic technique would be very useful. Dermoscopy is a noninvasive diagnostic technique allowing a more accurate diagnosis. Objectives: To differentiate DT and morpheiform basal cell carcinoma by means of dermoscopy. Methods: Here, we describe the dermoscopic features of a case of DT, and make a direct clinicopathological correlation by using the horizontally cut slides provided by Mohs micrographic surgery. Results: On dermoscopy, DT shows well-defined borders and an ivory-white color, as well as prominent arborizing telangiectasias in the central area and on the right side. There are no leaf-like structures and no ovoid nests. This observation confirms and completes the first dermoscopic analysis of DT reported in the literature so far.

Desmoplastic trichoepithelioma: A clinicopathological study of three cases and a review of the literature

“…On histopathological examination, the lesion is usually well circumscribed, symmetrical and confined to the papillary dermis and upper two-thirds of the reticular dermis (9). The three cases examined within the present study exhibited the typical clinical and histopathological features of DTE that have been described by previous studies (4,5,10).…”

“…DTE may resemble other benign and malignant tumors clinically and histologically, including MBCC, MAC, cutaneous metastatic breast cancer and syringoma (9,24).…”

“…The most common features of DTE are that the tumor is slow-growing, white-gray to flesh-colored, indurated, centrally depressed, non-ulcerated and 2-18 mm in diameter (9). The tumor has an annular border, is present as a papule or plaque, and predominately occurs on the face.…”

The dermatoscopic universe of basal cell carcinoma

“…The latter group comprises sebaceous, follicular, eccrine and apocrine neoplasms, several of which have been characterized as dermatoscopic “mimickers” of BCC [30]. Trichoblastoma, trichoepithelioma, pilomatrichoma, cylindroma and eccrine poroma are only some of the entities reported to dermatoscopically exhibit linear branching vessels and blue-gray globules, similar to those seen in BCC [29,31–35]. In this context, it has been suggested that the differential diagnosis might be facilitated by the observation that the vessels of adnexal tumors are usually less focused, or by the detection of whitish or yellowish structures that have been associated with follicular and sebaceous tumors, respectively [29].…”

Dermatoscopia del tricoblastoma

“…Aunque se ha señalado que el fondo blanco perlado o marfileño puede ser una característica de los tricoepiteliomas desmoplásicos frente al fondo blanco brillante de los tricoepiteliomas «clásicos», se trata de un hallazgo dermatoscópico difícil de diferenciar y para el cual no se ha estudiado la concordancia entre observadores 15 .…”