[Prospective study of thromboses of the subclavian vein after setting implantable venous access systems in cervico-facial cancerology].

Seventy-eight consecutive patients treated by chemotherapy for ENT cancers and having a subclavian catheter for venous access were studied prospectively to assess the prevalence of venous thrombosis. Thrombosis of the subclavian vein was demonstrated clinically in 4 patients and by ultrasonography in 7 patients. The prevalence of thrombosis was 14.1%. No clinical or biological predisposition factor could be identified. Subclavian thrombosis mostly occurred during the second month after implantation (91% of cases). Ultrasonography seems the most useful non-invasive technique for the diagnosis of subclavian thrombosis.