Outcomes of 3-weekly doxorubicin and cyclophosphamide followed by paclitaxel (AC/T) in a randomized trial (RCT) compared to a case-control matched British Columbia (BC) breast cancer population.

Abstract

1037 Background: NCIC CTG MA.21 was a North American RCT of 3 adjuvant chemotherapies (adjCT), of which one was 3-weekly AC/T. We compared Relapse Free Survival (RFS) for this standardised adjCT given in MA.21 to that in a general population from a BC database, using a matched case-control design. Methods: Matching was based on age +/- 3 years (y) and MA.21 stratification factors: number of positive nodes [NP], surgery type, and estrogen receptor (ER). Patients (pts) who received > 1 cycle of AC/T were included. RFS was defined as time from randomisation (per protocol, AC/T started within 5 days) to recurrence for MA.21, and from first AC/T to recurrence for BC. A sensitivity analysis using HER2 negative (HER2-) pts was done, as testing and trastuzumab (TZ) use changed over time. RFS was estimated with Cox survivor plots, adjusting for factors significant in multivariate Cox step-wise forward regression. Results: 473 of 671 BC pts were matched to 473 of 696 MA.21 pts. Median follow up was 8 y and median t...