[HTML][HTML] An aCGH classifier derived from BRCA1-mutated breast cancer and benefit of high-dose platinum-based chemotherapy in HER2-negative breast cancer …
MA Vollebergh, EH Lips, PM Nederlof, LFA Wessels… - Annals of oncology, 2011 - Elsevier
Annals of oncology, 2011•Elsevier
Background Breast cancer cells deficient for BRCA1 are hypersensitive to agents inducing
DNA double-strand breaks (DSB), such as bifunctional alkylators and platinum agents.
Earlier, we had developed a comparative genomic hybridisation (CGH) classifier based on
BRCA1-mutated breast cancers. We hypothesised that this BRCA1-like CGH classifier could
also detect loss of function of BRCA1 due to other causes besides mutations and,
consequently, might predict sensitivity to DSB-inducing agents. Patients and methods We …
DNA double-strand breaks (DSB), such as bifunctional alkylators and platinum agents.
Earlier, we had developed a comparative genomic hybridisation (CGH) classifier based on
BRCA1-mutated breast cancers. We hypothesised that this BRCA1-like CGH classifier could
also detect loss of function of BRCA1 due to other causes besides mutations and,
consequently, might predict sensitivity to DSB-inducing agents. Patients and methods We …
Background
Breast cancer cells deficient for BRCA1 are hypersensitive to agents inducing DNA double-strand breaks (DSB), such as bifunctional alkylators and platinum agents. Earlier, we had developed a comparative genomic hybridisation (CGH) classifier based on BRCA1-mutated breast cancers. We hypothesised that this BRCA1-likeCGH classifier could also detect loss of function of BRCA1 due to other causes besides mutations and, consequently, might predict sensitivity to DSB-inducing agents.
Patients and methods
We evaluated this classifier in stage III breast cancer patients, who had been randomly assigned between adjuvant high-dose platinum-based (HD-PB) chemotherapy, a DSB-inducing regimen, and conventional anthracycline-based chemotherapy. Additionally, we assessed BRCA1 loss through mutation or promoter methylation and immunohistochemical basal-like status in the triple-negative subgroup (TN subgroup).
Results
We observed greater benefit from HD-PB chemotherapy versus conventional chemotherapy among patients with BRCA1-likeCGH tumours [41/230 = 18%, multivariate hazard ratio (HR) = 0.12, 95% confidence interval (CI) 0.04–0.43] compared with patients with non-BRCA1-likeCGH tumours (189/230 = 82%, HR = 0.78, 95% CI 0.50–1.20), with a significant difference (test for interaction P = 0.006). Similar results were obtained for overall survival (P interaction = 0.04) and when analyses were restricted to the TN subgroup. Sixty-three percent (20/32) of assessable BRCA1-likeCGH tumours harboured either a BRCA1 mutation (n = 8) or BRCA1 methylation (n = 12).
Conclusion
BRCA1 loss as assessed by CGH analysis can identify patients with substantially improved outcome after adjuvant DSB-inducing chemotherapy when compared with standard anthracycline-based chemotherapy in our series.
Elsevier