Poster 062: Comparison of Reliability of the Vital Staining With Iodine and Toluidine Blue Solutions to Detect and Delineate Oral Epithelial Dysplasia and Carcinoma

Abstract

Some kind of oral leukoplakias progressed to malignancy a few months or years later, suggesting the importance of correct diagnosis and treatment of these lesions from the standpoint of early detection and prevention of oral cancers. We have used the vital staining test with iodine (modified Lugol’s iodine solution) and toluidine blue (TB) solutions to detect and delineate cancerous lesions of oral mucosa as an adjunct diagnosis. Object: The iodine staining method is used a lot in Japan, but in Europe and the United States, the TB staining test has been generally used. The purpose of this study is to compare the reliability of vital staining tests with iodine and TB solutions for detection and delineation of oral epithelial dysplasia and carcinoma. The study included 58 patients with oral precancer or malignant-suspicious lesion attending OMFS, Suidobashi Hospital, Tokyo Dental College from January 2000 to December 2006. Each of these patients took staining tests with 3% iodine and 0.5% TB solutions before surgical resection. The resected specimens were investigated histopathologically after operation. The results of the clinical and histologic diagnoses and the staining results were compared. The sensitivity, specificity, and the positive and negative predictive results were calculated. The result shows that sensitivity of iodine staining test was 77.3%, and that of TB staining was 91.2%. On the other hand, specificity of each staining test was 52.8% and 67.6%. Almost low-grade epithelial dysplasia showed only iodine-unstained area, but malignant lesions tended to accompany TB-positive part. We conclude that both iodine staining and TB staining is useful to detect oral carcinoma and epithelial dysplasia at the high rate. The iodine solution is useful to delineate dysplastic epithelium as unstained area, and TB-positive indicates that a malignant lesion is developing.