Abstract P1-17-03: Comparison of Long Term Outcome of Locally Advanced and Inflammatory Breast Cancers Treated with Dose Dense Neoadjuvant Chemotherapy

Abstract

Abstract Background: Inflammatory breast cancers (IBC) have a worse prognosis than locally advanced breast cancer (LABC) (KW Hance, JNCI 2005; 97:966-75). We report a series of LABC and IBC treated with dose dense anthracycline and cyclophosphamide and report the correlation between phenotypic features, pathological complete response (pCR) and disease free survival (DFS). Materials and methods: Between 1990 and 2003, 196 patients (pts) with LABC (105 pts) and IBC (91 pts) treated at St Louis hospital received 6 cycles (c) of dose dense Cyclophophamid (1.2g/m2 d1)-Epirubicin (E) (75mg/m2d1) q2w (SIM regimen). 133 patients had frozen biopsy allowing p53 determination. Surgery was done after chemotherapy. pCR was defined as no residual invasive tumor in breast and lymph nodes. Results: Median follow-up was 110 months. IBC were more often ER negative than LABC(52 % vs 34%), more often triple negative (33 % vs 22 %) and more often TP53 mutations .(60% vs 39 %). pCR in breast and lymph nodes was identical in LABC (17 pts,16%) and in IBC (14 pts, 16 %). Table I Pathological response and factors associated with pCR Negative ER and presence of TP53 mutations were strong predictive factors of chemotherapy efficacy in LABC and less in IBCS. histologically grade 3 was not predictive in IBC. Median disease free survival (DFS) was higher in LABC [103 months (m)] than in IBC (54 m), p=.031. Median Overall survival (OS) was not reached in LABC and was of 134 m in IBC (p = .015). A significant effect of ER status on DFS was found in LABC and IBC. When adjusting for ER, IBC still had a significantly shorter DFS (HR 1.64, 95%CI 1.12 to 2.39, P=.011). Similar results were found for OS. For TP 53, a significant interaction was found with LABC/IBC (p=0.017) with a risk for mutated patients in LABC (p=0.004) and a slight and nonsignificant increased risk in IBC patients (p=0.62). Estimated disease free survival at 15 years Conclusion: High risk patients treated with dose dense cyclophosphamide and anthracyclin have very long survival rate. Negativity of ER and p53 mutations are strong predictive factors of good outcome in LABC but less in IBC. This approach in ER-LABC should be prospectively studied.. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-17-03.