[Lymphoscintigraphy with double tracer technique in carcinomas of the head-neck region]

Lymphoscintigraphy has been used since the early 1960s to demonstrate lymphatic drainage of head and neck tumors, but did not prove satisfactory. With the increasing importance of highly sophisticated neck dissection procedures, lymphoscintigraphy may have greater diagnostic impact. This assumes that lymphoscintigraphy will allow an accurate correlation of lymphatic drainage with anatomic structures. In this paper, we report on a method of lymphoscintigraphy with simultaneous body contouring.

Double-tracer lymphoscintigraphy was performed in 78 patients with squamous cell carcinoma. Patients received 100 MBq 99mTc-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 99mTc-pertechnetate i.v. for body contouring. Planar images were obtained over 5 min each at 30 min and 4-6 h after injection from anterior, right lateral and left lateral using a LFOV-gamma camera.

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 observed. Thirty-six of 78 patients (46%) showed unilateral lymphatic drainage, and 14 of 78 (18%) showed bilateral drainage. In all 50 patients showing lymphatic drainage, lymph nodes could be easily assigned to the six cervical lymph node compartments described.

Double-tracer lymphoscintigraphy enables an accurate correlation of cervical lymph nodes and anatomic structures of the head and neck region. These findings suggest that the impact of these studies on the preoperative planning for neck dissection should be reevaluated.