PROX1 and primary central nervous system lymphoma: PROX1, along with other lymphatic markers (LYVE-1 and podoplanin), have been assessed among primary CNS lymphomas (PCNSL), diffuse large B-cell lymphomas (DLBCL), and primary glioblastoma multiforme (GBM) WHO Grade IV, in order to explain the metastatic behavior of the aforementioned CNS tumors [16].