Peripheral node addressin, a ligand for L-selectin is found in tumor cells and in high endothelial venules in endometrial cancer

Background: High endothelial venules (HEVs) are vessels specialized in the transport of lymphocytes shown to be implicated in various forms of cancer. They express peripheral node addressin (specifically recognized by the MECA-79 antibody). MECA-79 is also implicated in pregnancy through its expression by epithelial cells of the endometrium. However, the expression of MECA-79 by endothelial or epithelial (cancer) cells has never been studied in endometrial cancer. Material and Methods: In this retrospective study, we investigated the immunohistochemical expression of MECA79 in 40 endometrioid adenocarcinoma hysterectomy specimens and compared it with its expression in 30 noncancer hysterectomies. Results: HEVs were found in 22% of tumor specimens and in none of the non-cancer hysterectomies (p = 0.005) and were positively associated with higher grade tumors (p = 0.04). MECA-70 was expressed in tumor cells of 70% of carcinomas and in epithelial cells of 46.6% of normal endometria (p = 0.04). It was inversely associated with parametrial invasion (p = 0.03) and larger tumors (statistical trend of p = 0.07). MECA-79 expression was not associated with overall or progression-free survival. Conclusion: MECA-79 is found in HEVs and tumor cells in endometrial endometrioid adenocarcinoma.