Correlation between liver scintigraphy and computed tomography in the detection of liver metastases

Parallel scintigraphic and computed tomographic (CT-scan) examinations of the liver were carried out during the same observation period in 55 cancer patients in whom the liver status could be microscopically and macroscopically documented with regard to presence or absence of metastases. Scintigraphy was realized by means of 198Au or 99mTc-colloid using a rectilinear scanner or a gamma-camera; CT-scan images of the liver were obtained by a standard commercial instrument before and after injection of a contrast product. The liver was found to be normal in 38 out of the 55 observed patients and a metastatic involvement was seen in 17 cases. In 45 out of 55 cases, there was concordance between the results obtained by the two investigation methods and discordance in 10 cases. The sensitivity is 97% for the scintigraphy, 94% for the CT-scan and 100% for the common negative results. The specificity can be established as 64% for the scintigraphy, 65% for the CT-scan and 74% for common positive findings. It seems therefore that these two techniques present the same efficiency in the detection of liver metastases and that the results obtained are only partly complementary.