Venous thrombosis in an outpatient oncologic center: distribution, type, and comorbidities.

PURPOSE: To examine outpatient oncologic patients with venous thrombosis (VT) and correlate ultrasound findings with clinical characteristics and outcome.

MATERIALS AND METHODS: A retrospective study of 76 patients who had upper- and lower-extremity ultrasound examinations positive for VT formed the population, drawn from a total of 509 patients who presented over a 24-month period for non-invasive imaging. Clinical indication, demographics, sonographic findings, comorbidities, and development of pulmonary embolism in these patients were recorded. The Fisher-Freeman-Halton exact test was used to determine if test characteristics varied according to the location of VT (upper or lower extremity), the level of lower-extremity thrombosis (above the knee, below the knee, or both), the presence of active disease or remission, the chronicity or acuteness of thrombosis, and the presence of a central venous catheter (CVC).

RESULTS: In the study group, 64 patients had deep VT, and 12 had superficial VT. The most prevalent tumors in our study population were lymphoma and breast and lung cancers. The most common symptoms were swelling, pain, and erythema. Whereas 61 patients had active disease, 18 patients were in remission at the time of examination. Among 30 patients with upper-extremity VT, 18 had CVCs. Venous thrombosis involved the vessel containing the central venous line in 66% of studies. Pulmonary embolism developed in 8 patients who had lower-extremity VT despite an initiation of anticoagulation therapy. Patients with thrombus in the lower extremity had higher chance to develop pulmonary embolism, but there was no significant statistical difference in the level of lower-extremity thrombosis (above the knee, below the knee, or both), disease activity, and chronicity of thrombosis.

CONCLUSIONS: Venous thrombosis is most commonly acute and involves the lower extremity and the deep venous system above the knee. When VT involves the upper extremity, it is usually associated with a CVC. Pulmonary embolism is almost exclusively associated with lower-extremity VT and can occur despite anticoagulation therapy.