Does the Dual Use of Toluidine Blue and Hematoxylin and Eosin Staining Improve Basal Cell Carcinoma Detection by Mohs Surgery Trainees?

Abstract

BACKGROUND 

Although a number of Mohs surgeons currently use Toluidine blue stain, alone or in combination with hematoxylin and eosin (H&E), the effects on the trainees' histologic accuracy of adding toluidine blue to their H&E training was unknown.

OBJECTIVE 

To assess a trainees' histological accuracy when trained in a unit that routinely employs the dual staining technique and to determine whether the addition of toluidine blue improves, or impairs, the training process.

METHODS 

A fellow examined slides from 403 consecutive Mohs cases over 3 months, from the start of his training period. H&E slides for each case were examined first, followed by the toluidine blue slides, with recordings made of the diagnosis based on each. The fellows' findings were then checked against those of the senior Mohs surgeons and a consultant histopathologist.

RESULTS 

According to H&E alone, the fellow completely excised 96.3% of 352 basal cell carcinomas; this increased to 99.7% by adding toluidine blue. False-positive rates were 1.5% for H&E alone and 1.7% when using both stains.

CONCLUSION 

The addition of toluidine blue increased the diagnostic accuracy of the trainee, and we encourage the use and teaching of this stain in Mohs surgery.