Clinical And Prognostic Analysis Of Bilateral Primary Breast Cancer

Breast is the symmetrical organ of the body,estrogen effect on both of the them,so both sides have the risk to attack the cancer. Compared with people who did not develop breast cancer in the population, unilateral breast cancer patients have higher risk of bilateral breast cancer. The overall incidence of bilateral primary breast cancer rate was not high, but with the improvement of diagnosis and treatment method, 5 years and 10 years survival rate is greatly enhanced, which cause the BPBC incidence shows a tendency to increase.Objective To study the determining prognostic factors that affect the survival of patients with bilateral breast cancer.Methods The clinical data of 47 patients with BPBC, admitted to the First hospital of Jilin University from January 1997 to December 2008 were collected and analyzed on prognostic factors. Application of SPSS 13.0 statistical package was used for statistical analysis. The comparison of category variable data apply Fisher's exact test. Calculation of survival rate apply Kaplan-Meier, comparing the difference of sBPBC and mBPBC apply Log-Rank test. Prognostic analysis apply Cox regressive mode, the classified data of prognostic factors apply Kaplan-Meier and do Log-Rank test. Test levelα=0.05, lost data as censored Data.Result 47 BPBC patients account for 2.1% of operable breast cancer(47/2241), there are 14 sBPBC patients (0.6%, 14/2241) and 33 mBPBC patients (1.5, 33/2241). Compared of the age difference between sBPBC and mBPBC at the first cancer have statistical significance (χ2 =4.037,P=0.045). When BPBC compare with UBC, breast-feeding history, tumor size, tumor stage, and hormone receptor of the second tumor was statistically significant (breast-feeding historyχ2 =9.014,P=0.003; the primary tumor sizeχ2 =12.713,P=0.001; the second tumor sizeχ2 =40.098,P=0.000; the primary tumor stageχ2 =7.610,P=0.048; the second tumor stageχ2 =22.850,P=0.000; hormone receptor of the second tumorχ2 =7.065,P=0.020). Study the survival of the BPBC we can found that: when we used the the second tumor operation date as a starting point, 5-year and 10-year cumulative survival rate of BPBC were 79.8% and 74.2%, sBPBC were 77.9% and 70.7%, mBPBC were 84.2% and 76.3, UBC were 88.8% and 73.3%. Comparing the cumulative survival rate between BPBC and UBC apply Log-Rank test, the result is the difference have no significant(χ2 =1.79, P=0.209). Comparing the cumulative survival rate between sBPBC and mBPBC (χ2值=0.344,P=0.557), the result shows that generally the sBPBC survival rate is lower than mBPBC, but there is no significan. In this study, univariate analysis showed the tumor size, the lymph node metastasis and the clinical stage of the primary and the second side was BPBC prognostic factors. Comparison of the significant prognostic factors in groups, the result is the earlier stages, the higher survival rate, except the second clinical stage. The results of multivariate analysis showed that the second tumor size and the primary clinical stage are the prognostic factors of bilateral primary breast cancer.Conclusion 1. Morbidity: 47 BPBC patients account for 2.1% of operable breast cancer(47/2241), there are 14 sBPBC patients (0.6%, 14/2241) and 33 mBPBC patients (1.5, 33/2241).2. Risk factors: Breast-feeding is a protective factor in breast cancer. The ealier the first tumor stage, the more opportunity of the second side of the cancer occurs.3. Survival rate: when we used the the second tumor operation date as a starting point, UBC's 5-year survival rate was significantly higher than BPBC, but there is no significant; generally survival rates of sBPBC is lower than mBPBC, but the two groups was not significant. The interval on both sides of cancer is not the prognostic factor of BPBC.4. Prognostic factors: The results of multivariate analysis showed that the second tumor size and the primary clinical stage are the prognostic factors of bilateral primary breast cancer.5. According to the result of the multivariate analysis, the survival models of BPBC is: h(t,x)=H0(t)exp(1.491X1+1.410X2); X1 stands for the second tumor size, X2 stands for the primary clinical stage.