PAM-50 predicts local recurrence after breast cancer surgery in postmenopausal patients with ER+/HER2– disease: results from 1204 patients in the randomized ABCSG-8 trial

Abstract Background The aim of this study was to investigate whether the PAM-50-based 46-gene assay carries prognostic value for risk local recurrence breast cancer. Methods Austrian Breast and Colorectal Cancer Study Group (ABCSG) 8 RCT compared 5 years tamoxifen with 2 followed by anastrozole 3 in postmenopausal women endocrine receptor-positive This included patients from trial who had breast-conserving surgery whom tumour blocks were available PAM-50 analysis. Results Tumour 1204 analysis, 1034 these received radiotherapy. After a median follow-up 10.8 years, 23 events been observed, corresponding an overall 2.2 per cent. Univariable competing-risk analysis demonstrated that at low according (risk-of-recurrence (ROR) score less than 57) significantly lower incidence those high-risk group (0.1 (95 cent c.i. 0 0.7) versus (0.9 4.6) respectively; subhazard ratio (SHR) 17.18, 95 2.06 142.88; P = 0.009) 10 (0.4 2.0) 3.8 (1.9 6.6) cent; SHR 4.76, 1.72 13.17; 0.003). Multivariable analyses ROR score, age, size, nodal status, type surgery, tumor grade, trial-specific therapy confirmed independent factor recurrence. Analysis randomized radiotherapy or control after conservation showed not predictive effect. Conclusion can be used as tool hormone cancer treated therapy. test benefit