The Analysis Of Clinical Characteristics And Prognosis Of Triple-negative Breast Cancer

Background and Purpose:Triple-negative breast cancer(TNBC) represents the subset of breast cancer with aggressive biological behaviors and poor prognosis. It appears early recurrence and metastasis and is not likely to benefit from antioestrogen or anti-HER2 therapy, and in consequence received a wide publicity. To explore the prognostic risk factors of TNBC patients of this area and to strive to provide a basis for carrying out individual treatment , we analysis the clinical characteristics, prognostic factors and survival differences of 342 cases of TNBC and non-TNBC retrospectively in univariate and multivariate aspects in this study.Methods:We studied a cohort of 342 female patients with breast cancer, diagnosed between January 2000 and January 2001 at the First Hospital and China-Japan Union Hospital of Jilin University. All of the patients underwent surgery and received antioestrogen therapy, adjuvant chemotherapy and radiotherapy normatively. We used SPSS 13.0 statistical software package to sort and analyze the data of 342 cases of breast cancer patients and selected characteristic clinical indicators (age at onset, menstrual status, tumor size, TNM stage, clinical stage, whether triple-negative or not, number of positive lymph nodes, chemotherapy plan, disease-free survival, overall survival, metastatic sites, etc.), then according to SPSS13.0 package and processing requirements, we quantified these and usedχ2 to test the count data of clinical indicators, taking P <0.05 as statistical significant and P <0.01 as conspicuous significant statistical. We used Log-Rank test to compare the survival rate of patients with different prognostic index, size of a testα= 0.05. Cox proportional hazard regression model (Methods Forward LR: Maximum likelihood estimation based on partial forward method) is used to multivariate analysis and screening prognosis factor. Then establish Cox regression equation and calculate prognostic index.Results:This study involved 342 cases of breast cancer patients, including 56 cases of TNBC which accounts for 16.4% and most of its pathological type is invasive ductal carcinoma (64.29%). TNBC and non-TNBC both have a high incidence of middle-aged and the incidence rate of old-age group is low. TNBC onsets in women of all ages both before and after menopausal. TNBC patients are more likely to have lymph node metastasis (51.79%vs34.97%, p<0.05), and the local recurrence and distant metastasis rates are significantly higher than non-TNBC patients (21.43% vs10.49%, p<0.05). Furthermore,metastasis in bones is more likely to occur than in organ. But there is no statistical difference exists in the distribution of tumor size, clinical stage of TNBC groups. By the end of follow-up, 12 cases (21.43%) of 56 TNBC patients died and 29 cases (10.14%) of 286 non-TNBC patients died. The disease-free survival curves ( Figure 3.1) has a conspicuous statistical significant between TNBC and non-TNBC, P <0.01, and the overall survival curve (Figure 3.2) has a significant statistical significant, P <0.05. We used Log-Rank test to compare the survival rate of patients with different prognostic index and found that the prognosis of TNBC patients with older onset age , larger number of positive lymph nodes and later clinical stage should be worse than the other groups and other indicators (such as menstrual status, tumor size, delivery method, application of Taxol-type drugs, etc.) have no significant effect on prognosis. Cox proportional hazard regression model indicates that the tumor size (hazard ratio, 2.896; 95% confidence interval ,1.166-7.193; P<0.05) and the number of metastasis lymph node (hazard ratio,2.260; 95% confidence interval ,1.020-5.007; P<0.05) are the independent prognostic factors for TNBC patients.Conclusion:TNBC has strong aggressive and the number of metastasis lymph node, local recurrence and distant metastasis rate of TNBC are significantly higher than non-TNBC. Metastasis in bones is more likely to occur than in organ. Its prognosis is poor and worse with late age of onset ,late clinical stage and large number of positive lymph node. The tumor size and the number of metastasis lymph node are the independent prognostic factors for TNBC patients.