Skeletal scintigraphy. The use of technetium 99M-labeled complexes in the detection of early osseous involvement by metastatic tumors.

Skeletal scintigraphy using Technetium-99m ((99m)Tc) complexes was carried out in a series of 332 cancer patients. The results of scintigraphy were compared with the results of roentgenography and with the diagnostic usefulness of serum alkaline and acid phosphatase levels and the presence or absence of bone pain. In 25 percent of cases, lesions were first identified with scintigraphs. When metastastic lesions were present on both scintigraphs and roentgenograms, the number was greater on scintigraphs in 72 percent of cases. Six false negative studies were recorded (1 percent). Sixty percent of patients with early metastasis-that is, those with abnormal scintigraphs and negative roentgenograms-were asymptomatic. Serum alkaline and acid phosphatase levels were normal in 40 percent and 42 percent respectively of those with early skeletal involvement. Skeletal scintigraphy with (99m)Tc complexes is superior to other commonly employed techniques used to assess bone metastasis.