Pattern analysis of serum alpha-fetoprotein in the early diagnosis of hepatocellular carcinoma in liver cirrhosis

In a surveillance program for hepatocellular carcinoma (HCC), serum alpha-fetoprotein (AFP) was determined every 4 months in 164 patients with liver cirrhosis. Ultrasonography (US) was performed yearly or as dictated by abnormal AFP levels. During a follow-up of 32.5 +/- 20.8 months HCC was identified by US in 16 patients. In 9 of them the AFP levels rose steadily over 4 months, increasing 7, 8 and 12 months in 3 cases before the lesion became detectable by US. In 4 patients tumors developed despite persistently normal AFP levels. Nine more patients showed abnormal fluctuations of AFP but HCC was not detected. AFP sensitivity was higher at a low cut-off point (40 ng/ml) while specificity of the test appeared higher at the 200 ng/ml cut-off point. An AFP value rising steeply over a few months appeared more reliable than a fixed preset threshold in indicating carcinomatous transformation. Screening for AFP can be expected to uncover about 3/4 of HCC developing in cirrhotics with few false-positive reactions. The test may have a unique role in identifying a subset of liver tumors whose early expression is AFP production.