Research Article

Clinicopathologic and Prognostic Significance of Body Mass Index (BMI) among Breast Cancer Patients in Western China: A Retrospective Multicenter Cohort Based on Western China Clinical Cooperation Group (WCCCG)

Table 5

Multivariable Cox regression for DFS of breast cancer patients.

VariableMultivariate Cox Proportional Hazard Regression for DFS
HR†95% CIP value

BMI at diagnosis (kg/m2)
UW2.801.66 to 4.73< 0.001
NWReference
OW1.401.05 to 1.880.02
Age at diagnosis (years)0.980.96 to 1.000.02
Tumor size (cm)
≤ 1 cmReference
1>, ≤ 2 cm2.630.35 to 19.730.35
2>, ≤ 5 cm4.910.68 to 35.380.11
>5 cm8.451.16 to 61.650.04
No. of positive ALN
0Reference
1-31.270.84 to 1.920.25
≥41.721.23 to 2.420.002
Nuclear grade
IReference
II1.240.59 to 2.590.57
III2.231.04 to 4.790.04
ER
NegativeReference
Positive0.870.62 to 1.200.39
PR
NegativeReference
Positive0.760.53 to 1.090.130
HER2
NegativeReference
Positive1.671.10 to 2.550.02
Surgery
Non-surgeryReference
MRM0.080.02 to 0.28< 0.001
BCS0.070.02 to 0.28< 0.001
Others0.070.02 to 0.26< 0.001
Chemotherapy
NoReference
Yes0.560.36 to 0.890.01
Endocrine therapy
NoReference
Yes1.230.88 to 1.730.22
Radiotherapy
NoReference
Yes0.710.52 to 0.980.04

Disease-free survival (DFS) was defined as the time from surgery to the date of the first locoregional recurrence, first distant metastasis, or death from any cause.
†Multivariate analysis adjusted by BMI, age at diagnosis, tumor size, number of positive ALN, nuclear grade, status of ER, PR, and HER2, surgery, chemotherapy, endocrine therapy, and radiotherapy.
NW, normal weight (BMI, 18.5 to 24.9 kg/m2); UW, underweight (BMI, <18.5 kg/m2); OW, overweight and obese (BMI, >25 kg/m2); HR, hazard ratio; CI, confidence intervals; ALN, axillary lymph nodes; ER, estrogen-receptor; PR, progesterone receptor; HER2, human epidermal growth factor receptor 2; BCS, breast conserving surgery; MRM, modified radical mastectomy.