Demographic characteristics of the patients and results are shown in
Tables 1 and
2. The incidence of symptomatic axillary vein thrombosis was 0.38% (18/4,773). The 18 patients with symptomatic axillary vein thrombosis included 14 males and four females, and the mean age was 66.2 years (range: 53 - 82 years). Based on univariable analyses, age, gender, and type of cancer were significantly associated with the risk of symptomatic axillary vein thrombosis (
Table 3). In the18 patients, the cancer types included lung cancer (n = 7), pancreatic cancer (n = 4), and other tumors (breast cancer, esophageal cancer, hypopharyngeal cancer, Klatskin tumor, parotid gland cancer, rectal cancer, and tonsillar cancer). The incidence rates for symptomatic axillary vein thrombosis based on cancer types were 0.79% (lung cancer, 7/882) and 1.58% (pancreatic cancer, 4/253). Multivariable binary logistic regression analysis revealed that pancreatic cancer (P = 0.012, odds ratio: 16.903) and lung cancer (P = 0.047, odds ratio: 8.384) were significantly associated with the risk of symptomatic axillary vein thrombosis (
Table 4). Age and gender were not significantly associated with the risk of symptomatic axillary vein thrombosis on multivariable binary logistic regression analysis. Regarding implantation site, symptomatic axillary vein thrombosis developed in patients on the right side (15/3,769, 0.39%) and on the left side (3/1,004, 0.29%). Implantation site was not significantly associated with the risk of symptomatic axillary vein thrombosis (
Table 3).
The median time between insertion of a TIVAP and diagnosis of thrombosis was 35.5 days (6 - 292 days). Diffuse subcutaneous edema in the ipsilateral UE was diagnosed on UE-CT venograms in 13 patients, and edema was not detected on CT in two patients. All symptomatic patients had thrombosis in the axillary vein on CT images. Symptoms were improved in all treated patients including removal of TIVAP at the time of diagnosis and following anticoagulation therapy (
Figure 1). In the 18 symptomatic patients, tip locations were from the distal third of the superior vena cava to the right atrium in 16 patients and in the superior vena cava in two patients. The mean BMI value was 23.1. Among the patients with reported smoking status, nine patients were ex-smokers and one was a smoker. Metastatic lesions at the time of TIVAP insertion were detected in 10 patients. Based on the Khorana model, five patients were at high risk, seven patients at intermediate risk, and six patients at low risk.