Useful immunohistochemical indicators in canine mast cell tumours

Galectin-3 immunolabelling correlates with BCL2 expression in canine cutaneous mast cell tumours

Mast cell tumour (MCT) is the most frequent skin neoplasm in dogs. These tumours are characterised by variable behaviour and clinical presentation that make prognosis an important and challenging task in the veterinary practice. Galectin-3 (Gal-3) is known to influence several biological processes that are important in the cancer context and has been described as a prognostic marker for several human cancers. The aim of the present work was to characterise Gal-3 immunolabelling in canine cutaneous MCTs and to investigate its value as a prognostic marker for the disease. Thirty-four random cases of canine cutaneous MCT that were surgically treated with wide margins were included in this study. Gal-3 expression was evaluated using immunohistochemistry and the results were compared with the expression of apoptosis-related proteins, Ki67 index, histopathological grades, mortality due to the disease and post-surgical survival. The majority of the MCTs (65.8%) were positive for Gal-3. Gal-3 immunolabelling was variable among the samples (2.7%-86.8% of the neoplastic cells). The protein was located in the cytoplasm or in the cytoplasm and the nucleus. Gal-3 positivity was correlated with BCL2 expression (P < 0.001; r = 0.604), but not with Ki67 and BAX. No significant differences were detected between histological grades or in the survival analysis. Gal-3 expression correlates with BCL2 expression in MCTs. Although an efficient marker for several human neoplasms, the results presented herein suggest that Gal-3 immunolabelling is not an independent prognostic indicator for this disease.

Occurrence and Distribution of Canine Cutaneous Mast Cell Tumour Characteristics Among Predisposed Breeds

Introduction

Breed predisposition to cutaneous mast cell tumours (MCT) in a population of dogs in Poland affected by various skin tumours was assessed, and the distribution of MCT characteristics such as histological grading, sex, age, and location, in predisposed breeds was evaluated.

Material and Methods

The retrospective epidemiological study included 550 dogs affected by cutaneous MCTs with a reference group of 2,557 dogs diagnosed with other skin tumours.

Results

A univariable logistic regression analysis was performed to determine the odds ratios (ORs) with 95% confidence intervals. The risk of high-grade MCTs was the highest for Shar-Peis (OR: 26.394) and American Staffordshire Terriers (OR: 2.897). Boxers (OR: 6.619), Labrador Retrievers (OR: 2.630), French Bulldogs (OR: 2.050), Golden Retrievers (OR: 1.949), and American Staffordshire Terriers (OR: 2.592) were mainly affected by low-grade MCTs. The high risk of MCT was calculated to be at the age of 4–6 years for Labrador Retrievers (OR: 2.686) and 7–10 years for Boxers (OR: 2.956) and French Bulldogs (OR: 9.429). MCTs were significantly more often located on the trunk in French Bulldogs (OR: 4.680), American Staffordshire Terriers (OR: 2.520), and Labrador Retrievers (OR: 1.948). There was no statistically significant correlation between gender and the occurrence of MCTs in the breeds.

Conclusions

The breed-predicated differences in the clinical course of MCTs suggest a genetic background for the tumours.