Venous thromboembolism significantly contributes to patient deterioration and mortality. Management of its etiology and anticoagulation treatment is intricate, necessitating a comprehensive consideration of various factors, including the bleeding risk, dosage, specific anticoagulant medications, and duration of therapy. Herein, a case of lower extremity thrombosis with multiple primary malignant tumors and high risk of bleeding was reviewed to summarize the shortcomings of treatment and prudent anticoagulation experience.

中文翻译：

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多原发恶性肿瘤合并血栓形成的挑战性抗凝治疗：病例报告并文献复习。

静脉血栓栓塞显着导致患者病情恶化和死亡。其病因和抗凝治疗的管理是复杂的，需要综合考虑各种因素，包括出血风险、剂量、具体抗凝药物和治疗持续时间。本文回顾1例下肢血栓合并多发原发恶性肿瘤、出血风险高的病例，总结治疗中的不足和谨慎抗凝的经验。