Objectives: A 5 years old Holstein cow was presented to the Teaching hospital, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad in autumn 2010. Anorexia and low milk production was reported by the owner. On gross observation, a hemorrhagic firm, pink, cobblestone, ulcerated mass was seen between anus and vulva. Complete clinical and clinicopathological examination also showed that the cow was suffering from endometritis and left displacement of the abomasum. Materials & Methods: Local anesthesia was induced by administration of a 2% lidocaine solution in a small area around the mass and under sterile condition, a biopsy specimen was taken and sent to pathology lab in 10% formalin solution. Tissue specimens were processed routinely and 6 μm sections were sta ined with Hematoxylin and eosin.A blood sample with anticoagulant was also obtained for complete blood count (CBC). Allthe factors were within normal range but, CBC showed the cow was anemic (the mucous membrane was also pale). Rectal temperature and pulse rate was slightly elevated but the respiratory rate was higher than normal88breaths/min Results & Conclusion: Histopathologic examination revealed pleomorphic keratinocytes showing hyperchromatism and atypical mitotic figures. There were nests and island of tumor cells invading the underlying connective tissue containing horn pearls in the center. There was also necrosis and inflammation. An invasive SCC was diagnosed. SCC is a malignant tumor of epidermal cell. Skin at mucocutaneous junctions such as the eyelid and vulva in cattle lacking pigments inthese locations are at greatest risk. The incidence of SCC in vulva is les s than eyelid .There are several factors that are associated with the development of a SCC including prolonged exposure to ultraviolet light, lack of pigment within the epidermis, lack of hair or a very sparse hair coat at the affected sites .This tumor was also observed in nose, udder, and ear tips . Treatment may be easy or impossible based on the size of the tumor, anatomical location and the lack of presence of obvious metastasis to regional lymph nodes. In our case, the mass was very large and extensive, so surgical remove was very difficult . Because of poor prognosis due to SCC and two other concurrent diseases (endometritis and LDA), it was recommended to the owner to take the animal to slaughter house.

Keywords