Nuclear size in dog skin mast cell tumors predicts outcome

Abstract

Classification schemes regarding canine subcutaneous mast cell tumors (csMCTs) remain elusive, lack consensus, and are prone to interobserver variability and bias. This observational study aimed to assess the reproducibility and the prognostic significance of volume-weighted mean nuclear volume (), a stereological estimation offering insights into nuclear size and its variability, in csMCTs. Thirty csMCTs were selected with information regarding outcome, andwas estimated using the "point-sampled intercept" method. Interobserver and intraobserverreproducibility yielded concordance coefficients near or above 0.90. Regarding previously reported risk factors (pattern, mitotic count, and multinucleated cells), no statistically significant differences were identified between patterns and clinical outcome, nor between patterns and; however, the infiltrative pattern was represented more in the poorer outcome group and had highervalues. When comparingand clinical outcome, a statistically significant difference emerged. Cases with poorer outcomes had highervalues (= 192.9) than cases with more favorable outcomes (= 120.5), and this association was statistically significant on both univariable and multivariable analyses. This study suggests thatis highly reproducible and is associated with clinical outcome in csMCTs.