Lens Culinaris Agglutinin-reactive Fraction of Alpha-fetoprotein as a Tumor Marker in a Patient With Nonseminomatous Germ Cell Tumor With Normal Alpha-fetoprotein Level.

Alpha-fetoprotein (AFP) is an essential tumor marker for diagnosis and treatment of nonseminomatous germ cell tumor (NSGCT). Some NSGCTs have no conventional tumor markers specific for NSGCT; that is, they are negative for both AFP and human chorionic gonadotropin. AFP-L3 is one of the fractions of AFP, separated by affinity to the lectin Lens culinaris agglutinin. It has been well-investigated and used for diagnosis and treatment of hepatocellular carcinoma. In the field of urology, ALP-L3 has been used for evaluating remaining or recurrent NSGCTs after treatment. Recently, a highly sensitive AFP-L3 assay has become available and enabled the accurate measurement of AFP-L3 at AFP concentrations of 3 ng/mL or higher. As a result, it is possible to detect AFP-L3 abnormalities at normal AFP levels with less than 10 ng/mL. We herein report a case of NSGCT with normal AFP and abnormal AFP-L3, successfully treated using AFP-L3 as a tumor marker throughout the treatment. (C) 2019 Elsevier Inc. All rights reserved.