Factors Associated and Survival Outcomes Among Japanese Patients with Solid Cancer Who Developed Deep Vein Thrombosis (DVT)

Objective: Deep vein thrombosis (DVT) is a common and serious complication in patients with cancer. We retrospectively analyzed patients newly diagnosed with solid cancers in a Japanese cohort. Patients or Materials: We retrospectively reviewed the medical records (2013– 2020) of Japanese patients with solid cancers who were suspected of having DVT and were diagnosed and treated at Ehime University Hospital. Controls were patients with solid cancers in whom DVT was suspected on physical examination and/or laboratory testing but subsequently ruled out by definitive imaging. Candidate risk and prognostic variables were extracted from electronic medical records. This was a single-center cohort study. Results: Among the initial 1399 patients, 224 with DVT and 560 without DVT (as controls) were included in the final analysis after excluding those with incomplete medical records, missing diagnostic tests, or unclear medical histories. The median overall survival (OS) period was 5.87 years for patients with DVT and 6.81 years for patients without DVT (p=0.0014). Anemia (Hb < 11 g/dl) and thrombocytopenia (Plt < 15 x 104 / μL) were found to be strong risk factors related to an increased incidence of DVT. Female cancer patients with DVT had a significantly worse outcome than those without DVT (p=0.028). Analysis of OS in patients with DVT associated with gynecological cancers following treatment with three different direct oral anticoagulants (DOACs; edoxaban, rivaroxaban, and apixaban) indicated that those treated with apixaban had a significantly worse outcome than those treated with the others (p=0.019) in this Japanese cohort. Conclusion: Japanese patients with solid cancers, particularly those with gynecologic cancers, tend to have poorer outcomes when DVT co-occurs with anemia and low platelet counts. In addition, the choice of DOAC for DVT treatment may be associated with differences in prognosis. These exploratory findings require more detailed, adjusted analyses and confirmation using other datasets or populations. Keywords: cancer patient, deep vein thrombosis, DVT, prognostic factor, direct oral anticoagulant, DOAC