| Objective:The purpose of this study was to retrospectively analyze the impact of BMI on the prognosis of breast cancer in overweight,under 160 cm tall patients from China.Methods:We retrospectively analyzed data from 525 breast cancer patients diagnosed between 2003 to 2010 in a multi-center of China.The height<160cm is defined as a small stature.After applying the exclusion criteria,315 patients with complete data were retained.Their clinical and pathological characteristics were compared using the chi-square test.Survival analysis was performed with the Kaplan-Meier method.Univariate and multivariate analyses were performed using Cox regression to calculate hormone receptor status,HER-2 status,lymph node status,age,BMI and tumor size hazard ratio(HR),and 95%confidence intervals(95%CI).Results:1.Clinicopathological characteristics of patients and tumorsWe retrospectively analyzed the data from 525 breast cancer patients.According to exclusion criteria,137 cases were eliminated from the study.Seventy-three patients were lost to follow-up.In total,315 patients with complete data were included.First,patients were divided into five groups according to the BMI China Standard Index as follows:BMI<18.5;18.5<BMI<23.9;24<BMI<26.9;27<BMI<29.9;BMI≥30.summarizes the clinical and pathological characteristics of the enrolled 315 breast cancer patients.We analyzed five BMI subgroups for age,tumor size,lymph node status,ER status,PR status,HER-2 status,and molecular subtypes.The results showed a strong correlation between BMI and age,whereas there was no statistically significant correlation between BMI and tumor size,lymph node status,ER status,PR status,HER-2 status,or molecular subtype.Further,we compared these correlations according to the clinical baseline characteristics of the patients,described in Tables S1-S4.In Luminal A and B,the BMI was correlated with age.Across the different groups formed according to characteristics,no other correlation was statistically significant.2.Prognosis in different BMI groupsAfter comparing clinical and pathological characteristics,we studied the relationship between BMI and disease prognosis.We performed an OS analysis using the Kaplan-Meier method.The DFS and OS rates in different BMI groups were not statistically different.Using Cox regression analysis,we next assessed whether BMI was an independent factor affecting prognosis.Neither univariate nor multivariate analyses supported that BMI could be a prognosis predictor.Univariate analysis showed that tumor size and lymph node status can be used as independent predictors of DFS and OS.Multivariate analysis confirmed that tumor size and lymph node status can be used asindependent predictors of DFS and OS.3.Correlation between recurrence and BMI in groups of patients with cancers of different molecular typesWe performed a BMI subgroup analysis within four groups of patients with breast cancers of different molecular types,i.e.,Luminal A,Luminal B,Herb-2,and Triple negative.Within each molecular type,the number of patients without relapses in each BMI subgroup was greater than the number of patients who relapsed.Contingency in each molecular type group was not statistically significant.After studying the recurrence in BMI subgroups within different molecular type groups,patients were divided into 5 groups according to BMI.We wanted to study the recurrence in each BMI group independently of cancer molecular type.Within each BMI group,the number of patients with relapse was smaller than that of patients without relapse.Next,we calculated the recurrence rate according to the site of metastases.Twenty-four cases of recurrence occurred.4.Investigation of weight as a potential risk factor for breast cancer recurrenceAfter studying the link between BMI and recurrence of breast cancer,we investigated a potential link between weight and recurrence in order to determine potential range of weight associated with increased risks.Fewer patients relapsed in all groups than those who did not.Then we counted the specific recurrence sites of patients,including 24 cases of liver metastasis,accounting for 26.4%of the total recurrence rate,30 cases of bone metastasis,accounting for 33.0%of the total recurrence rate,40 cases of lung metastasis,accounting for 44.0%of the entire recurrence rate,There were 8 cases of brain metastases,accounting for 8.8%of the total recurrence rate,and 44 cases of other site metastases,accounting for 48.4%of the entire recurrence rate.After analyzing 5 BMI groups and 5 weight groups,BMI was further divided as follows:normal and thin for BMI≤23.9;overweighed for BMI between 2 4 and 26.9;obese for BMI between 27 and 29.9;severely obese for BMI≥30.We compared the recurrence in the normal and thin groups with that in the overweighed,obese,and severely obese groups.Thiscomparison indicated no significant differences between groups.5.Comparison of therapies undergone by patients from the three overweight groupsWe next investigated if weight had an influence on the type of treatment undergone by the patients.There was no significant difference in treatments among the three overweight groups.Breast-conserving surgery was performed in 10.3%of the overweight group,3.8%of the breast-conserving surgeries were performed in the obese group,and no breast conservation surgery was performed in the severely obese group.However,there were no statistically significant differences between groups.There were no significant differences among the three overweight groups in terms of chemotherapy,choice of chemotherapy regimen,or whether or not endocrine therapy was performed.Conclusion:1.BMI is closely related to age.There was no statistical significance between BMI and tumor size,lymph node status,ER status,PR status,HER-2 status and molecular subtype.2.Tumor size and lymph node status are closely related to the prognosis of breast cancer patients.3.We found that the BMI of the Chinese Southwest region population is not related to the prognosis of breast cancer patients. |
PDF Full Text Request