Diagnosis of metastatic liver cancer.

To the Editor.— The study by Tempero et al (1982;248:1329) comparing the sensitivity and specificity of the liver scan and biochemical liver tests was carefully performed with only minor drawbacks. One of these is the failure of the authors to indicate the technique for liver imaging, specifically the number of views obtained and the number of counts or information density they sought. An inherent problem is the findings from liver biopsy or biopsies that remain normal in the face of cancer detected by other means. The sensitivity of multiple liver biopsies has not been shown to exceed 82% except in one study, averaging about 70%. 1,2 My only major argument with the authors is their contention that screening for hepatic metastases is best accomplished with liver function tests while the liver scan should be used only when these test results are abnormal. Having seen two cases with notably abnormal scans