Fig. 6

WWOX expression in canine MCTs by immunohistochemistry. Primary MCTs were graded using the two-tiered histologic grading scheme (N = 14 low grade, N = 5 high grade) and immunohistochemical staining for WWWOX was performed. Tumors were scored blindly by two board-certified veterinary pathologists using the specifications outlined in Table 1. Results were averaged between raters for comparison based on tumor grade. a Degree of staining intensity negatively correlated with histologic grade with high-grade MCTs exhibiting significantly lower stain intensity. b The percent of neoplastic cells staining was significantly decreased in high-grade MCTs as compared to low grade tumors. Weighted Kappa scores were determined and there was fair interrater agreement for both staining intensity and percent of cells stained (K = 0.264 and 0.273, respectively; statistical analysis: one-way ANOVA, ****p ≤ 0.0001)