IMAGING OF HEAD AND NECK TUMORS WITH POSITRON EMISSION TOMOGRAPHY AND[C-11] METHIONINE

Purpose: To evaluate the value of positron emission tomography and [C- 11]methionine in imaging of malignant tumors of the head and neck regi on. Methods and Materials: Forty-seven tumors of the head and neck wer e investigated with C-11-labeled methionine and positron emission tomo graphy before treatment. Because of the resolution limits of the posit ron emission tomography scanner, all tumors selected for the study wer e larger than 1 cm in diameter. Results: Forty-two (91%) of the 46 mal ignant tumors were clearly visible in the positron emission tomography image (squamous cell carcinoma, n = 26; lymphoma, n = 9; adenocystic carcinoma, n = 2; lymphoepithelioma, n = 1; adenocarcinoma, n = 1; tra nsitional cellcarcinoma, n = 1; esthesioneuroblastoma, n = 1; plasmocy toma, n = 1), while three (7%) squamous cell carcinomas were visible, but less easy to detect due to physiological accumulation of the trace r in the area under observation. Only one (2%) squamous cell carcinoma could not be delineated from the positron emission tomography image, and there was no uptake of [C-11]methionine in a benign pleomorphic ad enoma. No correlation was found between the uptake of [C-11]methionine and the histological grade in the subset of squamous cell carcinoma ( n = 30). High physiological uptake of [C-11]methionine was observed in the salivary glands and the bone marrow. Conclusions: Malignant head and neck tumors can be effectively imaged with positron emission tomog raphy using [C-11]methionine as the tracer.