Microwave-assisted silver-stain method in the diagnosis of canine mast cell tumors: Correlation with traditional methods by digital image analysis

An experimental development based on the combination of microwaves action with the Del Rio Hortega's silver carbonate method is presented. Twelve canine cutaneous mast cell tumors (paraffined embedding) were classifiedmorphologically into three grades. The impregnation was made with ammoniacal silver carbonate in a microwave oven during twelve seconds at 375W. The specific staining of mast cells granules was possible by omitting the formalin reduction. Statistical analysis was made to compare this technique, evaluated by digital image analysis, with toluidine blue and avidin peroxidase methods. Conjugated avidin peroxidase and Del Rio Hortega's silver carbonate method stained more mast cell than did any other method, suggesting that they may be a helpful addition to the differential diagnosis of canine mast cell tumors. Furthermore, this technique offers advantages over the other techniques, not only in the operation procedures but also in the definition of the histological details fundamental to the assessing of tumors.