trichoblastoma in a dog: a case report

Hair follicle tumors are typically benign and usually present as solitary masses, though they can occasionally be multiple. trichoepithelioma, originating from hair matrix cells, is the most commonly considered type. a 3-year-old vaccinated canine with a mass on its dorsum was referred to the small animal hospital at the faculty of veterinary medicine, university of tehran. during the physical examination, no clinical abnormalities were detected. fine-needle aspirate (fna) cytology examination revealed a dense population of neoplastic epithelial cells forming cohesive clusters or aggregates. these cells exhibited features consistent with basaloid epithelial neoplasia, with mild anisocytosis, a high nuclear-to-cytoplasmic ratio (n:c), basophilic cytoplasm, prominent nucleoli, and the presence of inflammatory cells within a hemodilution background. the cytological findings are most compatible with a basal cell tumor (trichoblastoma). to confirm the diagnosis, it is recommended to send the sample to the pathology department. the cytological findings are consistent with trichoblastoma, a benign tumor of the hair follicle. given the excellent prognosis with appropriate treatment, surgical excision or cryosurgery is recommended.