Dolichos biflorus agglutinin binding to intracranial germ-cell tumors: detection of embryonal components in germinomas.

Dolichos biflorus agglutinin (DBA) binding was examined in 32 cases of intracranial human germ-cell tumors. In embryonal carcinomas, intense DBA binding sites were found on the free surface and cytoplasm of embryonal cells. In teratomas, glandular structures often had positive DBA binding sites. Yolk sac carcinomas and choriocarcinomas showed negative DBA affinity. Of 19 cases of germinomas, 10 showed no DBA-positive cells, while sporadically and/or collectively distributed-DBA positive cells were found in the other 9 cases. Common brain tumors such as gliomas, neurinomas and meningiomas were negative for DBA staining. Considering the cellular carbohydrate structure, these findings suggest that DBA-positive cells in germinoma might be evidence of differentiation into embryonal or some somatic components. In addition, because of the absence of DBA binding sites in the common brain tumors, the identification of such binding sites in brain tumors might act as a marker for embryonal or somatic components, especially among germ-cell tumors.