Prognosis of patients with venous thromboembolism and cancer in India

Introduction: Venous thromboembolism (VTE) is common in cancer patients and is considered one of the leading causes of death. Although activation of coagulation system is linked to tumor biology and considered as poor prognostic feature, there are several temporary/provoking factors such as perioperative period, immobilization, and debility that may cause VTE in these patients. It is not clear whether patients with such provoked VTE have different prognoses compared to patients without provoked VTE. Aim: To understand the overall prognosis of patients with cancer-associated thrombosis deep vein thrombosis (DVT) and whether there is a difference in survival between patients who underwent surgery (with or without chemotherapy) and patients who did not undergo surgery. Materials and Methods: This is a combined retrospective and prospective study. Electronic medical records of all patients who underwent VTE treatment between September 2014 and September 2019 were reviewed. Only patients who had DVT in the lower limb associated with malignancy were included in the study. Demographics, clinical, type, stage and type of cancer, and prophylactic treatment received and mortality data were collected. Results: Of 1364 patients treated for VTE, 86 patients (6.3%) had cancer-associated DVT. The mean age was 57 years (range 26-80 years) and 52 patients (60.46%) were female. The most common malignancies were cervix (15.11%), breast (12.79%), and colorectal (12.79%). Majority (68.60%) of the cancer patients were in the stages III and IV, other than having malignancy the most common risk factors were age, obesity, and postsurgery. Forty-three patients had surgery (with or without chemotherapy/radiotherapy). The left leg was commonly involved (53.48%) and the site of thrombus was in iliac (51.68%), femoral (16.85%), or popliteal veins (2.24%). All patients were initially started on low-molecular-weight heparin (LMWH) and then switched to Non-Vitamin K antagonist oral anticoagulants (NOAC) in 29 patients (33.72%) and VKA in 43 patients (50%). In seven patients, LMWH was continued (8.13%). Fifty-seven out of 86 patients (66.27%) were available for follow-up. Eighteen out of 57 patients (31.57%) were alive with an overall mortality of 59.64% and 1 year mortality of 37.5%. In patients who underwent surgery (with or without chemotherapy/radiotherapy), the overall mortality was 58.13% compared to 85.71% in patients who did not undergo surgery. Conclusion: VTE in cancer patients is not uncommon in India and is associated with high mortality. Patients with provoked DVT due to surgery (perioperative period) might have better survival compared to patients who did not undergo surgery.