Cancer-associated thrombosis, low-molecular-weight heparin, and the patient experience: a qualitative study

Background: Venous thromboembolism is a common complication of cancer and its treatments. Treatment of cancer-associated thrombosis (CAT) differs from treatment of thrombosis in noncancer patients, requiring a daily injection of low-molecular-weight heparin (LMWH) for 6 months instead of an oral anticoagulant. Previous research suggested LMWH is an acceptable intervention in the treatment of CAT, yet clinical practice and therapeutic opportunities have changed in the decade since the study was conducted. Furthermore, in the previous study there was acknowledged selection bias in participant recruitment. There is increasing clinical use of the novel oral anticoagulants, although their efficacy and safety is yet to be demonstrated within the cancer population. The experience of patients receiving anticoagulation for CAT will inform future practice with respect to quality of life and adherence to anticoagulation therapy. Aim: To explore the acceptability of long-term LMWH for the treatment of CAT in the contexts of living with cancer and quality of life. Design: Qualitative study of cancer patients who had been receiving LMWH for at least 3 months for CAT was undertaken. Audiotaped semistructured interviews were conducted and transcribed. Thematic analysis was undertaken until theoretical saturation. Setting/participants: Fourteen patients attending a palliative care or CAT clinic were interviewed. Participants had been receiving LMWH for a median 6 months. Results: Participants reported distressing symptoms associated with symptomatic CAT, which they rated as worse than their cancer experiences. LMWH was considered an acceptable intervention despite challenges of long-term injections. Several adaptive techniques were reported to optimize ongoing injections. Participants would only favor a novel oral anticoagulant if it was equivalent to LMWH in efficacy and safety. Conclusion: Although LMWH remains an acceptable intervention for the treatment of CAT, its long-term use is associated with bruising and deterioration of injection sites. These are considered an acceptable trade-off against their strongly negative experiences of symptomatic venous thromboembolism.