Thrombosis Across Female-Specific Malignancies: From Chemotherapy-Driven Risk to Prophylaxis and Drug Interactions

Cancer-associated thrombosis (CAT) remains a leading cause of morbidity and mortality among patients with cancer. Female-specific malignancies such as breast, ovarian, endometrial, and cervical cancers exhibit distinct thrombotic profiles driven by hormonal, anatomical, and treatment-related factors. This review summarizes current evidence on CAT in these malignancies, emphasizing chemotherapy- and hormone-related risk, thromboprophylactic strategies, and pharmacologic considerations in anticoagulant selection. Ovarian cancer carries the highest incidence of venous thromboembolism (VTE), ranging from 5% to 14%, largely due to advanced disease, ascites, and platinum-based chemotherapy. Breast cancer accounts for approximately 15% of all CAT cases, with increased risk observed among patients treated with selective estrogen receptor modulators or cyclin-dependent kinase 4/6 inhibitors. Endometrial cancer presents a moderate to high risk for CAT, especially in obese patients and those receiving hormonal therapy or radiation. Prophylaxis with low-molecular-weight heparins (LMWHs) or direct oral anticoagulants (DOACs) effectively reduces VTE incidence in high-risk patients. In the API-CAT trial, reduced-dose apixaban (2.5 mg twice daily) was non-inferior to full-dose therapy for extended anticoagulation after 6 months of treatment (2.1% vs. 2.8%; adjusted subhazard ratio, 0.76; 95% Confidence Interval (CI), 0.58-0.97; p = 0.001). Drug-drug interactions with anticoagulants and agents such as doxorubicin, ribociclib, and tamoxifen warrant individualized anticoagulant selection and close monitoring. A patient-centered pharmacotherapeutic approach, supported by multidisciplinary collaboration, is essential to optimize thrombosis prevention and minimize bleeding risk in women with cancer.