Estrogen Receptor–Positive, Progesterone Receptor–Negative Breast Cancer: Association With Growth Factor Receptor Expression and Tamoxifen Resistance

摘要: Background: Clinical data indicate that estrogen receptor – positive/progesterone negative (ER + /PR − ) breast cancers are less sensitive to tamoxifen than ER tumors. It has also been reported may be effective in tumors overexpress either HER-2 or HER-1 (epidermal growth factor receptor) and signaling through these receptors reduces PR expression experimental models. We hypothesized more likely have an aggressive phenotype, express HER-2, benefi t from adjuvant therapy. Methods: biological features of 31 415 patients with were compared those 13 404 Association between disease-free survival (DFS) status was analyzed a subset 11 399 receiving Hazard ratios (HRs) 95% confi dence intervals (CIs) calculated using Cox regression Kaplan Meier analyses, all statistical tests two-sided. Results: frequent older patients, larger size, had higher S-phase fraction, aneuploid Furthermore, three times as many expressed (25% versus 8%; P <.001) 50% overexpressed (21% 14%; <.001). Among tamoxifen-treated women, recurrence among women expressing (HR = 1.9, CI 1.0 3.5; .05); stronger association worse DFS overexpression observed 2.3, 1.2 4.3; .006). However, results varied by status. tumors, not associated DFS. however, both 2.4, 5.4; .036) 2.6, 1.1 6.0; .022) likelihood recurrence. Conclusions: