Abstract
When indigocarmine was injected into the tissues surrounding head and neck tumors, the healthy surrounding tissue was stained blue and the carcinomatous region remained unstained. Under histological examination of the specimens, dye was found between collagen bundles and in the lymphatic vessels. Dye was not found in the tumor and parenchematous tissue such as glands. It is suggested that the injection of dye in the surrounding tissue may help in the identification of tumor margins and contribute to the safe resection of the tumor.