The Clinical Pathological Features And Prognosis Of BMI And Breast Cancer

Objective: with the growth of national economy and the improvement of people's livelihood in China,the incidence of breast cancer is on a constant rise,ranking top on the list of malignant tumors in China and even the world,and becoming a vital factor that jeopardizes the health of women.Overweight and obesity have represented a major threat to public health across the world with approximate 2.1 billion people have BMI greater than 25kg/m2 [1].The correlation between obesity and malignant tumor gradually comes to people's awareness.However,the current research shows that obesity may make normal people more vulnerable to breast cancer but has not produced clear conclusion on the affected women,particularly,the findings of prognostic analysis on Chinese affected women are inconclusive.Accordingly,this study was made to analyze the impact of BMI on the distribution,clinical characteristics,and prognosis of breast cancer through reorganizing,following-up,and summarizing the case files of patients who were diagnosed by the Breast Cancer Center of the Tumor Hospital of Hebei Province as primary breast cancer and ready to take surgery,chemotherapy,radiotherapy and other standardized treatment from 2010 to 2012,with a view to providing some reference for the future treatment of breast cancer patients.Methods: From January 2010 to December 2012,a total of 3380 women were diagnosed by the Tumor Hospital of Hebei Province as primary breast cancer patients with complete clinical data.According to WHO classification criteria,BMI = body weight(kg)/ Height(m)2,people with BMI <18.5kg/m2 are underweight,people with 18.5-24.9kg/m2 are normal,people with 25.0 kg/m2-29.9 kg/m2 are overweight,people with BMI ? 30 kg/m2 are obese.Patients were divided into two groups at 25.0 kg/m2: low BMI group(BMI <25.0 kg/m2)and high BMI group(?25 kg/m2).According to the screening criteria of this test,the final enrollment was 3178 cases,including 1707 cases(53.7%)in low BMI group and 1471 cases(46.3%)in high BMI group.All patients were follow-up at least one time(up to three times),by telephone,visit,re-hospitalization,hospital review,household registration.Disease-free survival(DFS)was calculated from the date of the operation,with first recurrences,local or distant,being scored as an event,and patients without recurrence were censored at the time of last follow-up or death.Overall Survival(OS)from the date of operation,with death from any cause being scored as an event.Patients who were still alive at the time of last follow-up were censored.Upload the follow-up data accurately to the SPSS19.0 statistical package to do the statistical analysis.Results:1 BMI and clinical pathological characteristicsThe effect of BMI on age,tumor size,ER(Estrogen receptor),Her-2(Human growth factor receptor 2)and molecular subtype was statistical significant(P <0.05).Patients with high BMI were elder(than the 50-year-old)who has larger tumor and more ER positive and Her-2 negative features.Among high BMI group,positive hormone receptor accounted for a larger share(48% vs 41.7%)while in low BMI group,the triple-negative breast cancer patients(12.0% vs 1.2%)and positive Her-2(19.8% vs 17.4%)accounted for a larger share.2 BMI with prognosisThe results showed that there were differences between OS survival curves in two BMI group(P <0.05),but there was no significant difference between in DFS compared with the two groups.In the stratified analysis,the OS of high BMI group was relatively shorter than low BMI group(P <0.05),while DFS was no significant difference.While in group of younger patients(age<50),the role of BMI is not obvious.3 The Univariate and multivariate analysis of patientsUnivariate analysis showed that tumor size,lymph node metastasis,pathological grade,ER,PR,Her-2,Ki-67 were the significant factors to DFS and OS of breast cancer patients(P<0.05).Multivariate analysis showed that lymph node metastasis,tumor size,pathological grade,PR and Ki-67 were independent prognostic factors of DFS(P<0.05).BMI,lymph node metastasis and PR were the independent prognostic factors of OS(P <0.05).Conclusion:1Compared with low BMI patients,BMI ? 25.0 kg/m2 of breast cancer patients seems older,larger tumor,later stage.Compared to low BMI group,high BMI group with more invasive pathological features and biological indicators(P <0.05).2 BMI,lymph node metastasis and PR expression are the independent prognostic factors of OS(P <0.05).Among them,high BMI is an independent poor prognostic indicator for breast cancer.