PLXNB1 and neoplasm: Furthermore, in ovarian cystadenocarcinomas, the membrane and cytoplasm of the tumor cells was positive for Plexin-B1 immunostaining (Figure 1D), and a significant difference (P = 0.008) in positive staining was observed between samples with lymph node metastasis (75.00%) and those without lymph node metastasis (44.23%).