LYMPHOSCINTIGRAPHY IN DOUBLE TRACER TECHN IQUE IN PATIENTS WITH HEAD AND NECK CARCINOMAS

Lymphoscintigraphy has been used since the early 1960s to demonstrate lymphatic drainage of head and neck tumors, but did not prove satisfac tory. With the increasing importance of highly sophisticated neck diss ection procedures, lymphoscintigraphy may have greater diagnostic impa ct. This assumes that lymphoscintigraphy will allow an accurate correl ation of lymphatic drainage with anatomic structures. In this paper, w e report on a method of lymphoscintigraphy with simultaneous body cont ouring. Methods: Double-tracer lymphoscintigraphy was performed in 78 patients with squamous cell carcinoma. Patients received 100 MBq Tc-99 m-colloid in 0.1-0.2 ml in 3-4 peritumoral localizations. Ten patients were injected during surgery. Two milliliters of perchlorate solution were given orally in order to block the thyroid. Twenty minutes later patients received 50 MBq Tc-99m-pertechnetate i.v. for body contourin g. Planar images were obtained over 5 min each at 30 min and 4-6 h aft er injection from anterior, right lateral and left lateral using a LFO V-gamma camera. Results: The thyroid was not visualized in any of the patients. In 28 of 78 patients (36%), the injection site was the only focal activity seen. In 50 of 78 patients (64%), lymph drainage was ob served. Thirty-six of 78 patients (46%) showed unilateral lymphatic dr ainage, and 14 of 78 (18%) showed bilateral drainage. In all 50 patien ts showing lymphatic drainage, lymph nodes could be easily assigned to the six cervical lymph node compartments described. Conclusions: Doub le-tracer lymphoscintigraphy enables an accurate correlation of cervic al lymph nodes and anatomic structures of the head and neck region. Th ese findings suggest that the impact of these studies on the preoperat ive planning for neck dissection should be reevaluated.