1825P - Prevention and prophylaxis (thromboprophylaxis - ACT) of cancer associated thrombosis (CAT) in high risk oncology patients: ACT4CAT

Background

CAT is common cause of death and many complications in cancer patients. There is a need for thrombosis management across the natural history of cancer due to its dynamic nature. Anticoagulant therapy is the cornerstone of CAT prevention and treatment.

Methods

A prospective, observational study conducted by HeSMO across Greece, aiming to record the clinical practice of CAT prophylaxis in solid tumors. Ambulatory active cancer patients, receiving thromboprophylaxis for highly thrombotic tumors, are enrolled after signing informed consent.

Results

Preliminary results from 17 oncology departments are presented. From 272 enrolled patients, 260 (95.6%, mean age: 66 years, mean weight: 75 Kg.) have completed the second visit. Tumor types included: lung 31.5%, pancreas 19.7%, colorectal 11.6%, gynecological cancers 8.5%, stomach 7.7%, bladder 6.2%, etc. 76.8% of patients had metastatic disease. Most patients (62.6%) were at 1^st line treatment. Vast majority (87.8%) were treated with High-Risk for Thrombosis Chemotherapy Agents (HRTCAs). Regarding Khorana score, 75% had score ≤2. All patients were receiving anticoagulation agents as thromboprophylaxis (92.7% tinzaparin, 5.4% fondaparinux, etc) with average duration 5.7±3.5 months. 69% received higher than standard prophylactic dose. Higher thromboprophylaxis doses were administered more frequently in metastatic disease 75% compared to 56% in non-metastatic setting (OR: 2.4, 95% CI: 1.1-5.1, p=0.02). Moreover, higher doses were administered in patients receiving erythropoietin (OR: 2.4, 95% CI: 1-6.1). Three patients (1.2%) experienced thrombotic events and five minor bleeding events (1.9%).

Conclusions

Oncologists are alerted about CAT negative influence in cancer patients’ prognosis. In active cancer ambulatory patients, factors contributing to thrombotic burden such as high thrombotic risk tumor type, metastases, use of HRTCAs along with drug-drug interactions, apart from Khorana score, are considered as decisive factors to apply thromboprophylaxis. Effective doses under the duration of anti-neoplasmatic treatment are both safe and efficient.

Clinical trial identification

NCT03909399.

Editorial acknowledgement

Legal entity responsible for the study

Hellenic Society of Medical Oncology (HeSMO, http://www.hesmo.gr/en), Athens, Greece.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.