The role of vital tissue staining in the marginal control of oral squamous cell carcinoma.

Since vital staining has been advocated as a sensitive method of displaying epithelial atypia, 14 oral squamous cell carcinomas were stained immediately preoperatively with toluidine blue and then resected 1 cm outside clinically abnormal or positively staining tissue. The integrity of the entire tissue margin was histologically examined in each case. Whilst vital staining delineated all 14 invasive carcinomas at the centre of each resected specimen, 10 foci of carcinoma-in-situ or severe dysplasia were identified not to have stained at the resection margins. Toluidine blue may, therefore, be an adjunct in identifying invasive tumour at mucosal resection margins. However, it would appear to be of no benefit in delineating positive resection margins due to carcinoma-in-situ or severe dysplasia, and hence it may be of little value in reducing the incidence of local recurrences.