375 Effect of adjuvant chemotherapy (ACT) with or without anthracyclines on first line CEF in metastatic breast cancer patients (PTS)

Abstract

The effect of previous ACT with or without anthracyclines on the overall survival (OS), progression free survival (PFS) and response rate (RR) was evaluated in 326 metastatic breast cancer pts entered into 4 consecutive randomized trials and treated with CEF (Cyclophosphamide, Epidoxorubicin, 5-Fluorouracil) as first line CT. 154 (44%) pts did not receive previous ACT, 143 (44%) and 39 (12%) pts received CMF-based and anthracycline-based ACT, respectively. Response to CEF was observed in 161 (49.4%) pts. At univariate analysis, pts who received prior ACT had a significantly lower probability of response than pts who did not: 43% versus 58% (P = 0.02). No difference between CMF-based (RR 43%) and anthracycline-based (RR 44%) ACT was observed. Stepwise logistic regression analysis indicated that ACT, metastatic site and previous hormonotherapy for metastatic disease, were the most important factors in predicting the RR. At the multivariate analysis ACT was one of the strongest factor associated with a poor PFS. Median OS was 17.9 months. Pts who did not receive ACT had a longer survival (21.1 months) compared to pts previously treated with CMF-based (15.3 months) or anthracycline-based (15.8 months) ACT. Previous ACT adversely affects RR, PFS and OS in metastatic breast cancer pts treated with CEF regimen as first line chemothorapy. No difference between pts previously treated with CMF-based or anthracycline-based ACT was observed. The effect of previous ACT with or without anthracyclines on the overall survival (OS), progression free survival (PFS) and response rate (RR) was evaluated in 326 metastatic breast cancer pts entered into 4 consecutive randomized trials and treated with CEF (Cyclophosphamide, Epidoxorubicin, 5-Fluorouracil) as first line CT. 154 (44%) pts did not receive previous ACT, 143 (44%) and 39 (12%) pts received CMF-based and anthracycline-based ACT, respectively. Response to CEF was observed in 161 (49.4%) pts. At univariate analysis, pts who received prior ACT had a significantly lower probability of response than pts who did not: 43% versus 58% (P = 0.02). No difference between CMF-based (RR 43%) and anthracycline-based (RR 44%) ACT was observed. Stepwise logistic regression analysis indicated that ACT, metastatic site and previous hormonotherapy for metastatic disease, were the most important factors in predicting the RR. At the multivariate analysis ACT was one of the strongest factor associated with a poor PFS. Median OS was 17.9 months. Pts who did not receive ACT had a longer survival (21.1 months) compared to pts previously treated with CMF-based (15.3 months) or anthracycline-based (15.8 months) ACT. Previous ACT adversely affects RR, PFS and OS in metastatic breast cancer pts treated with CEF regimen as first line chemothorapy. No difference between pts previously treated with CMF-based or anthracycline-based ACT was observed.