Squamous cell carcinoma with clear cell differentiation in an equine eyelid

A case of lipogranulomatous conjunctivitis in a horse

OBJECTIVE

To describe a case of lipogranulomatous conjunctivitis in a horse.

ANIMAL STUDIED

A client-owned 12-year-old Standardbred gelding presenting with chronic conjunctivitis and palpebral masses.

METHODS

Complete ophthalmic examination, surgical excision, histopathology, and bacterial culture of biopsy samples were performed.

RESULTS

Upper and lower eyelids of both eyes were affected, with multiple yellow-to-white nodules on the palpebral conjunctiva, adjacent to the eyelid margin. Nodule removal was achieved via partial tarsal plate excision. Histopathological examination revealed granulomatous inflammation and large droplets of presumed free lipid in the conjunctival lamina propria. The animal was diagnosed with lipogranulomatous conjunctivitis. No postoperative ocular discomfort was observed for months; however, 3 years later, new conjunctival nodules were noticed, requiring a second surgical procedure on three of the eyelids. Transient entropion in the left lower eyelid was observed 2 months after the second surgery, and no recurrence of conjunctival nodules was observed after 18 months of follow-up.

CONCLUSION

To our knowledge, this is the first report of lipogranulomatous conjunctivitis in horses.

Correlation between p53 and Mdm2 expression with histopathological parameters in cattle squamous cell carcinomas

Background and Aim:

Squamous cell carcinoma (SCC) is the most common form of carcinoma in cattle. Histopathological grading systems have been utilized over several decades for estimating the malignancy of cattle SCCs. This study aimed to detect p53 and Mdm2 expression in different SCC cases in cattle and correlate their expression with the SCC histopathological grading.

Materials and Methods:

Cattle SCC cases were collected at the Veterinary Teaching Hospital in Nineveh. The SCC grading system categorized the cases histologically based on their differentiation grade into three groups: Well, moderately, and poorly differentiated. The SCC cases were subsequently verified for p53 and Mdm2 immunoexpression.

Results:

Fourteen of 16 examined cattle SCC samples tested positive for p53 expression. Moreover, 15 out of the 16 SCC samples tested positive for Mdm2 expression. The increased immunoreactivity of both p53 and Mdm2 was associated with a poor histological grading of the cattle SCC. There is a positive correlation between the nuclear expression of p53 and Mdm2, and the degree of differentiation and the number of mitotic figures in the examined cattle SCC samples.

Conclusion:

Our results demonstrate an increased p53 and Mdm2 expression in cattle SCC cases characterized by poor histopathological grading, thus suggesting an essential role of these molecules in the development of moderately and poorly differentiated SCC in cattle.