Comparison of clinical records between the two groups.
There was no statistical difference in age,
BMI and physical performance between the two groups (Table 1).
The two groups were completely matched in tumor site,
pathological type and tumor stage,
and had no statistically significant difference in metastasis (Table 2).
Stomach (25 cases,
43.10%) and colon (20 cases,
34.48%) were the most frequent tumor sites.
Adenocarcinoma was the main pathological type (86.21%).
Most subjects were in advanced stage and many of them had metastasis (75.86%).
Among tumor related therapies,
proportion of deep vein catheterization (with in 3 months),
surgery (within 2 months) and chemotherapy (within 30 days) were higher in the UPE group than the control group.
While there was no statistical difference in targeted therapy (within 30 days) between the two groups (Table 3).
As for VTE related history,
proportions of subjects with a history of bed rest or immobilization were statisitically different between the two groups.
While there was no statistical difference in comorbidities ( Charlson comorbidity index,
alcohol intake and VTE history.
Comparison of AVA measurements on CT.
Compared to the control group,
subjects in the UPE group had higher TAVA,
VAV/BMI and VAV/BSA (Table 5).
There was no statistical significant difference in VAV/SAV.
Results of univariate logistic regression analysis.
Univariate logistic regression analysis was conducted to evaluate the correlation between UPE and all the other factors we collected from clinical records.
The results revealed that there were 10 correlated factors with P < 0.10 including TAVA,
deep vein catheterization within 3 months,
surgery within 2 months,
chemotherapy within 30 days,
best rest or immobilization.
And 9 of these factors except for smoke demonstrated P < 0.05 (Table 6).
Regardless of AVA related variables,
univariate logistic regression analysis indicated that 4 factors were correlated with the occurrence of UPE including deep vein catheterization within 3 months (OR:8.349；95%CI ：3.443，20.247),
surgery within 2 months (OR:6.736；95%CI ：2.720，16.682),
chemotherapy within 30 days (OR:3.333；95%CI ：1.211，9.171),
and bed rest or immobilization (OR:3.103；95%CI ：1.292，7.452) (Table 6).
Results of conditional multivariate logistic regression analysis.
Conditional multivariate logistic regression analysis was conducted separately between the occurrence of UPE and AVA related variables including TAVA,
VAV/BMI and VAV/BSA,
adjusting other correlated variables .And the results revealed that these 4 AVA related variables were all independent risk factors of UPE (Table 7).