Analysis Of Clinicopathologic Features And Prognosis Factors In Basal Like And Non-basal Like Triple Negative Breast Cancer

Objective: Triple-negative breast cancer(TNBC) is defined as lack of estrogen receptor(ER), progesterone receptor(PR) and human epidermal growth factor receptor-2( HER-2) expression.It is a subtype of tumor with distinct clinical and pathologic features. It can be divided into basal-like TNBC( BL-TNBC) and non-BL-TNBC by uniting the detection of EGFR and CK5/6 through IHC. Overseas study indicate the two subtypes have quite different clinicopathologic features and prognosis characteristics. Among these subtypes the basal-like TNBC is associated with poor prognosis. It is necessary to classify the triple-negative breast cancer which is useful for judgeing the diagnosis and guiding therapy.This article is aim to analyse the differences of the clinicopathologic features and prognosis factors between these two subtypes of 130 TNBC.Method: We studied a cohort of 130 female patients with TNBC and complet e clinical and pathological data, diagnosed between January 2010 and January2013 at the First affiliated hospital of Da Lian Medical University. All patient s were firstly diagnosed to be TNBC by IHC and had treated by surgery. Case s were divided into BL-TNBC subgroup with EGFR and CK5/6 one or both p ositive,both negative cases divided into non-BL-TNBC subgroup. We used the SPSS17.0 statistical software to analysis the difference of the age at diagnose,menstrual status, family history, pathological type, histological grade, tumor size,lymph node metastasis,clinical stage, postoperative treatment, local recurrence a nd distant metastasis, etc, as well as analysis the lymph node positive group a nd negative group of BL-TNBC and non-BL-TNBC subgroup, finally to discus s the differences in various clinical pathological features between the two grou ps.Results: 130 cases of female patients with TNBC in this study, grouped on the basis of sample, including 92 cases of basal like triple negative breast cancer(BL-TNBC),accounted for 70.8% of the total number and 38 cases of non-basal like triple negative breast cancer(non-BL-TNBC), accounted for 29.2%. BL-TNBC has younger onset age, bigger tumor diameter and higher histological grade than non-BL-TNBC, the difference is statistically significant. And in the menopausal status, family history,pathological type, lymph node metastasis, clinical stage and so on aspects of the differences are not statistically significant. In addition, we respectively classified BL-TNBC and non-BL-TNBC subgroup of the lymph node positive group and negative group,suggesting that in the lymph node negative group, BL-TNBC group also has younger onset age, larger tumor diameter and higher histological grade, the difference is statistically significant. And in the lymph node positive group, the differences in various clinical pathological features between the two subtypes are not statistically significant. The two subtypes in postoperative treatment, recurrence,metastasis and survival situation in terms of the comparative analysis can be concluded that BL-TNBC group and non-BL-TNBC group in postoperative chemotherapy was 78.3%(72/92)及 76.3%(29/38),two groups of patients with postoperative radiotherapy proportion was 21.7%(20/92)及 21.1%(8/38),we didn’t conclude any statistical difference(P > 0.05). To follow-up as(on January 1, 2015)the median follow-up time of 40 months(25 ~ 60 months), follow-up rate was 81%(105/130),with a total of 43 cases patients(33.1%)experienced local recurrence and distant metastasis, 28 patients were dead(21.5%). Local recurrence and distant metastasis rate in BL-TNBC were higher than non-BL-TNBC(13.0%vs7.9%,23.9%vs15.8%), in addition pulmonary and brain metastasis have a higher incidence,but in this sample data the two groups in local recurrence rate,distant metastasis rate and metastases parts all showed that there was no significant difference(P > 0.05),this conclusion may consider to the smaller sample size, shorter follow-up time and incomplete follow-up data of the two groups. To follow-up as BL-TNBC group of mortality is higher than that of non-BL-TNBC, respectively 26.1%(24/92) and 10.5%(4/38), and the two groups have statistical differences(P < 0.05).Combination of the two subtypes of the comparison of clinical pathological features, in this study, we can think that the BL-TNBC has a relatively poor prognosis than non-BL-TNBC. In addition to analyse the expression of CK56 and EGFR, the difference of their expression is statistically significant by chi-square test(P < 0.05),the positive expression rate of CK5/6 is higher than that of EGFR, and the expression of the two indexes is irrelevant.Conclusions:1.Basal-like TNBC have younger onset age, larger tumour size and higher histologic grade.2.In the lymph node negative group, basal-like TNBC have larger tumour size and higher histologic grade than non-BL-TNBC, while in the lymph node positive group, the two subtypes have no significant differences in various clini cal pathological features.3.The rate of local recurrence, distant metastasis and mortality in Basal-lik e TNBC are higher than non-BL-TNBC. Combined with the differences of the two groups in clinical pathological features prompt that BL-TNBC has a poorer prognosis than non-BL-TNBC.4. In this study the differences between the expression of CK5/6 and EGFR are statistically significant,the positive expression rate of CK5/6 is higher than that of EGFR, and the expression of the two indexes is irrelevant.