Cutaneous paraneoplastic syndrome in a cat with thymoma.

Feline cutaneous paraneoplastic syndrome is a rare disorder associated mainly with pancreatic carcinoma and thymoma. In this report the authors describe the case of a 12-year-old cat with paraneoplastic exfoliative dermatitis associated with thymoma. Lateral radiographic examination of the chest showed a small subtle soft tissue density in the ventral part of the first and second intercostal space, which together with skin changes suggested thymoma. Because of pain associated with the skin condition, costs of treatment and the risk associated with surgical treatment, the owner chose euthanasia of the cat. Post-mortem examination revealed a tumour which was diagnosed as thymoma by histopathological examination.

Tumor-associated carbohydrate antigens: Sialyl Lea and T/Tn antigens in canine mammary tumors.

Twenty-eight canine mammary tubulopapillary carcinomas and 14 simple adenomas were studied by immunohistochemistry for the expressions of the tumor-associated carbohydrate antigens. Sialyl Le(a) was detected in 71.42% of the malignant and 92.84% of the benign tumors. Staining with anti-T and anti-Tn monoclonal antibodies revealed that 85.70% of the tubulopapillary carcinomas expressed T and Tn antigens. In contrast, 50% of the adenomas did not express T antigen, and 42.85% of them were only weakly stained for this carbohydrate structure. In the case of Tn antigen, the majority (57.14%) of samples was weakly stained, and no binding was observed in 35.71% of the analyzed specimens. Comparison of average values of reaction intensity (IRS) scale for malignant versus benign tumors by the Mann-Whitney U-test revealed a significant relationship between T and Tn antigens expression and type (malignant vs. benign) mammary tumors. Based on the results obtained, it is suggested that each of the studied antigens can be treated as a tumor-associated antigen of canine mammary tumors. However, only the T and Tn antigens seem to be associated with malignant transformation of mammary gland cells and to be of potential value as diagnostic markers.

Immunohistochemical expression of protein p53 in neoplasms of the mammary gland in bitches.

The aim of the study was to investigate the presence of protein p53 in correlation with other tumor traits: histological type, tumor grade and proliferative activity. Material for the investigation comprised mammary gland tumours collected from dogs, the patients of veterinary clinics, during surgical procedures, and archival samples. Alltogether 21 adenomas, 31 complex carcinomas, 35 simple carcinomas and 12 solid carcinomas were qualified for further investigation. No protein p53 expression was found in adenomas. Cancers show positive reaction in 32.5%. The highest percent of p53 positive neoplasms was observed in solid carcinomas and neoplasms with the highest degree of histological malignancy. The smallest number showing this expression was observed in adenomas and the highest was characteristic for solid carcinomas. Considering the tumour grading, it was found that an increase in neoplasm malignancy was positively correlated with the number of the cells showing the expression of protein p53. The differences were statistically significant. Statistically significant positive correlations were observed between the proliferative activity and protein p53 expression. Higher accumulation of protein p53 in more malignant neoplasms suggests that mutations of protein p53 can be responsible for higher proliferation in neoplasms with advanced progression of malignancy.

E-cadherin immunohistochemical expression in mammary gland neoplasms in bitches.

The aim of the study was to investigate E-cadherin expression in correlation with other neoplasm traits such as: histological type, the differentiation grade and proliferative activity. Material for the investigation comprised mammary gland tumours, collected from dogs, the patients of veterinary clinics, during surgical procedures and archival samples. All together 21 adenomas, 32 complex carcinomas, 35 simple carcinomas and 13 solid carcinomas were qualified for further investigation. E-cadherin expression was higher in adenomas as compared with carcinomas but lower in solid carcinomas as compared with simple and complex carcinomas. More over, the expression of E-cadherin decreased with the increase in the neoplasm malignancy and proliferative activity (value of the mitotic index and number of cells showing Ki67). The study has shown that the expression of E-cadherin can be used as a prognostic factor.