Histopathological and Immunohistochemical Study of Trichoblastoma in the Rabbit

The study characterized the histopathological and immunohistochemical features of trichoblastoma in 27 rabbits, examining 30 tumors. Trichoblastomas were most commonly found on the neck, head, flank, and hindlimb. Histologically, the tumors were categorized into ribbon, trabecular, and mixed types, with 80% showing prominent fibroblastic aggregation (papillary mesenchymal bodies). Immunohistochemically, peripheral palisading basal-type cells were positive for CK14, while inner cells were positive for CK17, differing from normal rabbit epidermis and hair follicle profiles. The study suggested that uncontrolled embryonic trichogenesis might be involved in trichoblastoma development in rabbits, and highlighted the importance of papillary mesenchymal bodies as a histological feature.