Malignant trichoepithelioma (MTE) or matrical carcinoma is a neoplastic change of matrical and inner root sheet cells. It is generally described in dogs, with no sex predisposition. In this case, a glassy skin mass was taken from a 8-year-old, female mixed breed cat. Histopathologically, it was presented with the typical matrical cells islands, central keratinisation and necrosis, hyalinated co...

Multiple skin nodules, with histological features of adnexal tumours consistent with trichoepithelioma, were observed on the head and trunk of Syrian hamsters. Skin biopsies from 20 hamsters from five different colonies were affected, and two of the affected hamsters also had lymphoma. Two owners reported that 16 of 70 hamsters and 50 of 100 hamsters in their colonies had similar skin lesions. ...

BACKGROUND Appendageal skin tumors belong to a heterogenous group of tumors with specific histopathology. The aim of this study is to determine the pattern of appendageal tumors in skin biopsies done in our department. METHODS This is a 3-year retrospective descriptive study of all patients who were diagnosed to have skin appendageal tumors in our department, and the diagnoses were confirmed ...

Background: To distinguish a basal cell carcinoma (BCC) from a trichoepithelioma (TE) can be diffi cult even for an experienced dermatopathologist. Objective: In this study, we sought to reconfi rm the androgen receptors (AR) immunostaining pattern of BCC and TE and to determine whether AR immunoreactivity could serve as a useful maker to differentiate these two tumors. Methods: Twenty-one case...

Desmoplastic trichoepithelioma (DTE) is a rare benign adnexal tumor with the characteristic features of asymptomatic, solitary, annular, indurated and centrally depressed papules or plaques, most commonly occurring in younger individuals on the face. Microscopically and clinically, DTE may be difficult to distinguish from other cutaneous adnexal neoplasms, particularly syringoma, cutaneous meta...

BACKGROUND Cluster designation 23 (CD23) is generally used as a lymphoid marker. Its utility in cutaneous epithelial tumors has never been studied. In our routine practice, we observed that CD23 reacted strongly with eccrine and apocrine secretory coils. METHODS Immunohistochemical staining of CD23 was performed in a total of 131 cases of apocrine, eccrine, follicular and other cutaneous non-...

neous biopsies, yielding 69 collision tumors. Cascajo and colleagues found 54 collision tumors of malignant cutaneous neoplasms associated with seborrheic keratoses in 85,000 biopsies. The most common combinations found by Boyd and Rapini included basal cell carcinoma and nevus (14), basal cell carcinoma and seborrheic keratosis (8), nevus and seborrheic keratosis (14), actinic keratosis and ne...