Background: Superficial vein thrombosis (SVT) is a common and well known condition. Active cancer increases the risk of thrombosis, particularly for SVT associated with catheters in the upper limbs. Despite its frequency, cancer-associated SVT management is not addressed by current evidence-based guidelines, leading to heterogeneous clinical practices.

Objective: To describe the current management strategies for cancer-associated SVT among French vascular physicians.

Methods: We conducted a national cross-sectional declarative survey distributed to all the members of both the French Society of Vascular Medicine and the French Association for Oncological Supportive Care. The questionnaire explored demographics and clinical approaches to SVT associated with cancer, both in the lower and upper limbs, through proposed scenarios.

Results: A total of 136 physicians responded, of whom 132 (97.1%) were vascular specialists. SVT of the lower limbs was considered cancer-associated in 15% of cases in daily practice. Among respondents, 102 (75.7%) declared modifying their treatment strategy in the presence of cancer. Fondaparinux 2.5 mg/day (44.1%) and curative-dose low molecular weight heparin (30.9%) were the most common initial treatments. Treatment lasted six weeks in 50.7% of cases and was extended as long as cancer remained active in 38.7%. Oral relay was considered in 19.1% of cases, mainly with apixaban. For upper limb SVT, 27.7% were considered cancer-related, and one third were catheter-associated. Treatment was commonly stopped upon catheter removal.

Conclusion: This survey reveals substantial variability in the treatment of cancer-associated SVT. The absence of dedicated trials and specific recommendations highlights the urgent need for prospective studies to guide management in this complex clinical setting.