Toluidine blue staining as an adjunctive tool for early diagnosis of dysplastic changes in the oral mucosa

Prognosis of oropharyngeal squamous cell carcinoma depends on early diagnosis, despite advanced surgical techniques, the 5-year survival rate remains ~40-50%. Unfortunately, it is usually detected when it becomes symptomatic. This requires treatment which gives rise to a high rate of morbidity and mortality and, furthermore, early detection of oro-pharyngeal pre-malignant lesions is important to improve the survival rate and quality of life. Since dysplasia and in situ carcinoma contain much more DNA and RNA than the normal surrounding epithelium, the use of in vivo staining, by means of toluidine blue dye, is based on the fact that it is an acidophilic dye that selectively stains acidic ti…