Staining Characteristics of Mast Cell Tumor in a Hedgehog

A 2-year old female African hedgehog (Atelerix albiventris) weighing 645 grams was presented with a well circumscribed mass in the subcutaneous of the left shoulder. It measured $2{\times}2cm$ in size and had a hard texture. There were no clinical signs. In a fine-needle aspiration (FNA) cytological evaluation, mast cells were identified with Wright-Giemsa stain. Mast cell tumor was confirmed and characterized by surgical sampling and histopathological evaluation. Four stains (hematoxylin-eosin, toluidine blue, periodic acid-Schiff, and Safranin O) were examined in order to find an applicable stain for a mast cell tumor histopathological evaluation in hedgehog. This case showed that periodic acid-Schiff and toluidine blue staining were the most useful for assessment of a mast cell tumor in a hedgehog.