The utility of Lens culinaris agglutinin-reactive alpha-fetoprotein in the diagnosis of hepatocellular carcinoma: evaluation in a United States referral population.

BACKGROUND & AIMS: The percentage of Lens culinaris agglutinin-reactive (alpha)-fetoprotein (AFP-L3%) is proposed as a diagnostic and prognostic marker for hepatocellular carcinoma (HCC). We evaluated the utility of AFP-L3% for diagnosis of HCC in a US referral population. METHODS: This retrospective study included 272 patients: 166 with HCC and 106 with benign liver disease (chronic liver disease, 77; benign liver mass, 29). The AFP-L3% was measured using a clinical auto-analyzer. RESULTS: The AFP-L3% is not reported for a total alpha-fetoprotein (AFP) less than 10 ng/mL, and all patients with an AFP greater than 200 ng/mL had HCC; thus the AFP-L3% was noninformative for these patients. In patients with a total AFP of 10-200 ng/mL, an AFP-L3% greater than 10% had a sensitivity of 71% and a specificity of 63% for diagnosis of HCC. An AFP-L3% greater than 35% had a reduced sensitivity of 33%, but an increased specificity of 100%. The high specificity of the AFP-L3% cut-off of 35% allowed the confident diagnosis of an additional 10% of HCCs not diagnosed using an AFP cut-off of 200 ng/mL. After adjustment for AFP level, no association was observed between AFP-L3% and tumor size, stage, vascular invasion, grade, or survival. CONCLUSIONS: Patients with indeterminate total AFP values of 10-200 ng/mL present a diagnostic dilemma. We found that an AFP-L3% greater than 35% has 100% specificity for HCC in these patients. AFP-L3%, used in combination with AFP, may be a clinically useful adjunct marker for the diagnosis of HCC.

Cerebrospinal fluid oligoclonal bands in the diagnosis of multiple sclerosis. Isoelectric focusing with IgG immunoblotting compared with high-resolution agarose gel electrophoresis and cerebrospinal fluid IgG index.

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. We compared the diagnostic performance of isoelectric focusing (IEF) combined with IgG immunoblotting to high-resolution agarose gel electrophoresis for the detection of intrathecal synthesis of IgG due to the MS disease process. In 20 patients with definite MS, IEF and high-resolution agarose gel electrophoresis had sensitivities of 90% and 60%, respectively. In the 51 patients with no evidence of MS, the methods had specificities of 94% and 96%, respectively. With a prevalence of 15% in this test population, IEF and high-resolution agarose gel electrophoresis had positive predictive values of 73% and 73% and negative predictive values of 98% and 93%, respectively. The IEF method improves the sensitivity and the negative predictive value of the oligoclonal-banding assay, the IEF gels are easier to interpret, and the IEF assay requires a smaller cerebrospinal fluid volume.