[Liver metastases: diagnostic value of blood tests, scintiscanning, and laparoscopy (author's transl)].

In 90 patients with known extra-hepatic malignancy the liver was examined for metastases. The diagnostic value of clinical information, blood examinations, 99mTc scintiscan, and laparoscopy for the diagnosis of the liver metastases was evaluated. Clinical data (age, sex, time since onset of symptoms and localisation of primary tumor) are of no diagnostic value. The most reliable blood tests are alkaline phosphatase (AP) and GOT. The probability of liver metastastases rises with increasingly abnormal values of AP and GOT. However, the probability is not much greater in cases with highly abnormal values than in cases with only moderate elevation of AP and GOT. Diagnostic accuracy of AP is optimal by using a cutoff point of 76 U/l (sensitivity 79%, specificity 64%). Bilirubin, prothrombin time, haemoglobin and blood sedimentation rate are of very little value. Combinations of AP with these blood tests does not improve diagnostic accuracy. Therefore, it is not useful to determine more blood tests than AP alone. Informed reading of liver scans has a specificity of 75% and a sensitivity of 91%. Blind reading of scans has a sensitivity of 94% and a specificity of 95%. This diagnostic accuracy cannot be improved by additional blood tests. Laparscopy has a sensitivity of 85% and a specificity of 95%. Scanning and laparoscopy are complementary methods. When optimal diagnostic accuracy is required both methods should be used.