THU0226 DOES THE PRESENCE OF CLASSIC AND NOVEL ANTIPHOSPHOLIPID ANTIBODIES INFLUENCE THE RISK OF THROMBOSIS DEVELOPMENT IN PATIENTS WITH UTERINE MALIGNANCIES

Background Patients with uterine malignancies (UM) are at a higher risk of venous thromboembolism (VTE) than the general population. The malignancy itself, the treatment modalities including medication, surgery and also increased levels of leukocytes, platelets, and tissue factor-positive microvesicles contribute to the risk of developing VTE. Objectives Several authors have shown that the antiphospholipid antibodies (aPLs) can be detected in peripheral blood of patients (pts) with malignancies. However, whether or not the aPLs could induce thrombosis in pts with UM is not yet known. The aim of our study was to determine whether the presence of aPLs in patients with uterine malignancies is associated with higher VTE risk than in pts with non-cancer gynecological disorders (NCGD). Methods The study involved 151 female pts scheduled for gynecological surgery divided into two groups: Group I with UM (70 pts) confirmed by histopathological examination after surgery; group II with non-cancer gynecological disorders (NCGD) (81pts). The presence of aPLs was detected in patients’ serum before surgery using the commercially available test aPL-immunodot assay Anti-Phospholipid 10 Dot, for the qualitative detection of IgG or IgM antibodies. The statistical data analysis was performed using Statistica v13.0. The following aPLs were assessed in the study groups: IgM and IgG of a- cardiolipin; a-phosphatidic acid; a-phosphatidylcholine; a-phosphatidylethanolamine; a- phosphatidylglycerol; a-phosphatidylinositol; a-phosphatidylserine; a-annexin V; a-s 2-GP I and a-prothrombin. Results The VTE occurred significantly more frequently in pts with UM, compared to pts with NCGD. In UM group VTE was diagnosed before surgery in 9/70 (12.9%) pts; in NCGD group VTE was diagnosed in 3/81 (3.7%) pts, p=0.0001. We have obtained positive test results for classic and novel aPLs significantly more frequently in group I pts with UM (mainly a-s 2-GP I IgM and IgG; a-prothrombin IgM, a-annexin V IgM) than in group-II NCGD pts. The positive test for classic or novel aPLs was detected in 17/70 pts with UM (24,3%) and in 6/81 pts with NCGD (7.4%). The differences were statistically significant (p=0.003). All pts with thrombosis in group I (9 pts UM) were positive for at least 3 aPls (a-s 2-GP I IgM and IgG; a-prothrombin IgM, a-annexin V IgM). Conclusion The classic and novel aPLs are found more frequently in pts with uterine malignancies than in pts with non-cancer gynecological disorders. The higher risk of thrombosis is connected with malignancy and the presence of classic and novel aPLs. The better understanding of the relationships between thrombosis in cancer patients and its immunological determinants (presence of aPLs) may lead to reducing the morbidity and mortality associated with thrombosis in cancer and non-cancer gynecological disorders. We suggest that aPLs could be a novel biomarker of thrombosis risk in gynecological malignancies. Disclosure of Interests Andrzej Majdan: None declared, Magdalena Dryglewska: None declared, Jan Kotarski: None declared, Maria Majdan Speakers bureau: MSD, UCB, Abbvie, Roche