Application of in vivo stain of methylene blue as a diagnostic aid in the early detection and screening of oral squamous cell carcinoma and precancer lesions

Background: Early detection of oral malignant or precancerous lesion by screening individuals with high-risk factors may identify candidates who should receive treatment to prevent cancer progression and reduce patient mortality. Among the diagnostic tools, in vivo staining is advocated as a simple, inexpensive, and fairly sensitive method. Methods: The present study involved the examination of fifty-eight patients suspected of having oral malignant or pre-cancerous lesions by methylene blue staining. The results of methylene blue uptake were compared with a simultaneous biopsy of these lesions. The pathologically confirmed precancers and cancers were the positive targets of this screening, while benign epithelial lesions were sorted as negative subjects of screening. Results: The results revealed sensitivity of 90%, specificity of 69%, positive predictive value of 74%, and negative predictive value of 87%. Conclusion: We consider that methylene blue staining is a useful diagnostic adjunct in a large, community-based oral cancer screening program for high-risk individuals.