- Pathologic complete response (pCR) is a favorable prognostic indicator of relapse-free survival (RFS) in a real-world study of early breast cancer (eBCa), even triple-negative breast cancer (TNBC).
Why this matters
- This is the first real-world population-based study of its kind.
- Findings suggest that pCR is a valid surrogate outcome in clinical trials, as well as population-based settings.
- Retrospective population-based analysis of stage I-III BCa in the British Columbia Breast Cancer Outcomes Unit database, 2005-2010 (n=267).
- pCR was compared with residual invasive disease in the breast/axillary lymph nodes (RD).
- Primary outcome: RFS.
- Funding: None.
- Median follow-up: 7.4 years.
- 28% of patients achieved pCR; 72% had RD.
- 5-year RFS was 55% higher in the pCR group (84% vs 70% in the RD group; HR, 0.45; P=.01).
- 5-year breast cancer-specific survival (BCSS) was 61% higher in the pCR group (90% vs 77%; HR, 0.39; P=.01).
- In multivariate analysis, pCR was associated with better RFS (HR, 0.39; P<.01 and bcss p=".015).</li">
- In subgroup analysis, patients with TNBC (but not those with other subtypes) who achieved pCR had improved RFS (HR, 0.26; P=.02) and nonstatistically better BCSS (HR, 0.35; P=.09).
- Retrospective, observational design.