The doctoral thesis MD. Liubov Kastnerova (previous name Kyrpychova) is focused on the histomorphological and molecular biologic features of selected cutaneous epithelial and nonepithelial tumors and is structured as a commentary to the 20 articles published during four years, representing the completed scientific projects in the Ph.D. course. In eight papers, the author of the thesis is the first author, whereas she coauthored in the remaining 12 papers. The thesis is composed of the commented files of authors own publications and it is divided into cutaneous epithelial and nonepithelial tumors. The first section, «Cutaneous epithelial tumors», includes 14 articles that are subdivided into two parts: adnexal tumors (9 articles) and lesions of anogenital mammary-like glands (5 articles). Of the nine articles on adnexal tumors, there are 5 articles focused on various benign and malignant adnexal lesions with apocrine or eccrine differentiation. Novel findings in this part include the identification of hitherto unreported alterations of the MYBL1 gene in adenoid cystic carcinoma of the skin and lack of deletion of the 1p36 locus in this neoplasm; the lack of a correlation between cellular composition and the presence CRTC1-MAML2 fusions in hidradenoma, the absence of CRTC3-MAML2 fusions in this tumor,...