Evaluation of double vital staining with lugol's iodine and methylene blue in diagnosing superficial esophageal lesions.

OBJECTIVE

To evaluate the accuracy of double vital staining with lugol's iodine and methylene blue in the diagnosis of superficial esophageal lesions.

METHODS

Doubtful superficial esophageal lesions identified with conventional endoscope were sprayed with 3% lugol's iodine and 0.5% methylene blue in order and observed in detail after each staining. Depending on the mucosal staining, biopsy specimen was obtained and underwent pathological examination.

RESULTS

Using conventional endoscope, we found 356 lesions in 297 patients, among which 179 were esophageal squamous cell carcinoma and precancerous lesions (CAPs) (including 71 early esophageal squamous cell carcinoma, 23 esophageal high-grade intraepithelial neoplasias, 85 esophageal low-grade intraepithelial neoplasias) and 177 were non-cancer non-precancerous lesions (NCNPs) (i.e. esophagitis and esophageal squamous cell hyperplasia). Most of CAPs were lightly stained or unstained, while NCNPs were hyperstained after lugol's iodine stained. The specificity, sensitivity, positive predictive value, negative predictive value and accuracy of lugol's lightly stained and unstained for identifying CAPs were 34.5%, 100%, 60.7%, 100% and 67.4%, respectively. Most of CAPs were lightly stained or hyperstained, while NCNPs were unstained after double vital staining. The specificity, sensitivity, positive predictive value, negative predictive value and accuracy of double vital staining lightly stained and hyperstained for identifying CAPs were 97.7%, 100%, 97.8%, 100% and 98.9%, respectively. The accuracy of double vital staining for identifying CAPs was higher than that of lugol's iodine stained (p = 0.000).

CONCLUSION

The double staining with lugol's iodine and methylene blue significantly improves the detection and diagnosis of early esophageal squamous cell CAPs.