anahita borzouei

Pilomatricoma is a benign skin adnexal neoplasm. Various histological features are observed on microscopic examination. We aimed to evaluate this tumor’s demographic and histological features in detail. One hundred cases with a diagnosis of pilomatricoma were selected, and demographic and clinical data were entered into a checklist. The pathology slides were reviewed to confirm the diagnosis. The demographic profile of all patients, including age and gender, primary clinical impression, multiplicity of the tumor, microscopic features, and location of tumoral involvement, were extracted. Qualitative data were summarized using frequencies and percentages. Regarding descriptive analysis, the frequency of each histopathologic feature was calculated. Two groups of patients were identified regarding age. This tumor was more common in males among adult patients, while a female preponderance was seen in those under 18. Most lesions were located on the face (40%), followed by upper (32%) and lower (10%) limbs. In addition to well-known histological features, we observed intraepidermal pilomatricoma in two cases presenting unique histopathologic features. Both showed foci of suprabasal cleft formation, while one showed the Borst-Jadassohn phenomenon. These features, in addition to sebaceous differentiation and acantholysis of ghost cells, were not addressed in previous literature. Understanding the diverse and new histological features of pilomatricoma is necessary for differentiating it from other adnexal and soft tissue tumors.

Lichen planopilaris (LPP) is the most common form of immune-mediated scarring alopecia. We evaluated the histopathologic features of LPP in vertical sections of scalp biopsies and compared findings between the scarring and nonscarring phases of the disease. From June 2019 to June 2020, vertically sectioned scalp biopsies of 70 new cases of LPP were examined (H&E) according to North American Hair Research Society criteria. Furthermore, patients were divided into two groups based on either the presence or the absence of vertical fibrous bands, and other histopathological features were compared between these two groups. Characteristic findings of LPP were perifollicular lymphocytic infiltration (97.1%), follicular interface degeneration (60%), and perifollicular plasmacytic infiltration (21.4%). Vacuolar degeneration in the dermo-epidermal junction (38.6%), perifollicular lamellar fibroplasia (67.1%), loss of sebaceous glands (87.1%), perifollicular cleft formation (28.6%), and vertical fibrous tracts (65.7%) were also found. Furthermore, we found a significant correlation between the presence of fibrous tracts with both loss of sebaceous glands (P = 0.005) and the presence of lamellar fibroplasia (P = 0.015). The most common findings in the histopathological examination of LPP slides are perifollicular lymphocytic infiltration and loss of the sebaceous glands. Furthermore, sebaceous gland loss and perifollicular lamellar fibroplasia correlate with the scarring phase of LPP.