The response to neoadjuvant chemotherapy and prognosis of triple-negative breast cancer patients.

Abstract Abstract #5121 Purpose: It is said that triple negative breast cancer (TNBC) has poor prognosis. However, many study shows TNBC has better response to chemotherapy. Since neoadjuvant chemotherapy plays an important role to TNBC, we compared clinical and pathological response rate and prognosis between TNBC and non-TNBC. Patients and methods: This analysis retrospectively collected 2563 breast cancer patients for StageI-III who underwent surgery between January 2000 and September 2004 (median: 3.9 years) at National Cancer Center, Tokyo, Japan. We defined TNBC as Estorpgen and progesterone receptor negative and HER2 score 0-2+ by immnohistological report. There were 91 TNBC patients (23.1%) out of 400 patients (15.6%) who underwent neoadjuvant chemotherapy. Clinical and pathological response rate and Four-year progression free survival were compared between TNBC and non-TNBC. Results: There were 91 TNBC patients (23.1%). TNBC patients compared with non-TNBC had tendency to achieve cCR (91% vs 78%; p=.058) although TNBC had higher rate for cPD (6.6% vs 1.7%; p <.0001). Also TNBC tended to have higher pathological CR rate of which we classified pCR only for grade 3 cases, compared to non-TNBC (13.1% vs 7.2%; p= .042 ). Interestingly HER2 overexpression type also had higher rate for pCR. As for pPD rate, TNBC had similar rate compared to non-TNBC (5.5% v 4.3%). Four-year progression free- survival rate was higher for non-TNBC. However, TNBC had higher Four-year survival free rate only when pCR were achieved after neoadjuvant chemotherapy (99% vs 82%; p=.02). Conclusion: Patients with TNBC tend to have clinical and pathological response of either CR or PD. Although non-TNBC had better prognosis by four-year survival free rate, TNBC could have better prognosis if neoadjuvant chemotherapy resulted in pCR. There may be some way to predict the efficacy of neoadjuvant chemotherapy and prognosis by analyzing the shrink pattern. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5121.