Radionuclide scans in staging of carcinoma of the lung

Radionuclide scans are relatively accurate, non-invasive, diagnostic tools when used in patients with carcinoma of the lung with clinically suspected metastases. Their role as a screening or staging procedure in patients without signs or symptoms of metastases is less clear. Brain scans in asymptomatic patients have a low yield. Liver scans done in the absence of hepatomegaly or elevated liver function tests show a high per cent of false-negative and negative results. Bone scans appear to be of considerable value in patients with or without clinical evidence of metastases, in spite of limitations imposed by frequent false-positive results.