DETECTION OF METASTASES FROM HEAD AND NECK CANCERS

Before treatment for head and neck malignancies is begun, a search for distant metastases (DM) is performed. The first objective of this rev iew was to determine the accuracy of liver function tests (LFT), alkal ine phosphatase (AP) tests, and chest radiographs (CXR) in detection o f DM, Second, an effort was made to identify tumor characteristics whi ch are associated with a higher incidence of DM and therefore justify the use of more precise screening tools. An analysis of 97 patients wi th noncutaneous squamous cell carcinomas presenting to the Stanford He ad and Neck Tumor Board in 1991 revealed 17 DM in 14 patients, There w ere 10 pulmonary metastases, 5 bone metastases, and 2 hepatic metastas es. CXR had a sensitivity of 50% and a specificity of 94% for detectio n of pulmonary DM, AP tests showed a sensitivity of 20% and a specific ity of 98% for detection of bone DM, LFT had a sensitivity of 50% and an 81% specificity for demonstration of hepatic DM. A separate analysi s of 79 patients with known DM from two hospitals showed the incidence of DM to be increased in patients who had tumors of advanced stage, a dvanced T status, and poor histologic differentiation and to also be i ncreased in the presence of local-regional recurrence, There was littl e association of DM with N status. The sensitivity of CXR and laborato ry tests, which are currently used in evaluation for DM at most cancer centers, is disappointing; these tests should be viewed as gross scre ening examinations, We recommend a chest computed tomography scan in t he event of an abnormal CXR, a bone scan in the event of an elevated A P, and either an ultrasound or computed tomography/magnetic resonance imaging scan of the liver when elevated LFT levels are present, depend ing on tumor stage and differentiation.