Ki67 expression in the primary tumor predicts for clinical benefit and time to progression on first-line endocrine therapy in estrogen receptor-positive metastatic breast cancer.
Fiche publication
Date publication
septembre 2012
Auteurs
Membres identifiés du Cancéropôle Est :
Pr COUTANT Charles
Tous les auteurs :
Delpech Y, Wu Y, Hess KR, Hsu L, Ayers M, Natowicz R, Coutant C, Rouzier R, Barranger E, Hortobagyi GN, Mauro D, Pusztai L
Lien Pubmed
Résumé
We examined whether baseline Ki67 expression in estrogen receptor-positive (ER+) primary breast cancer correlates with clinical benefit and time to progression on first-line endocrine therapy and survival in metastatic disease. Ki67 values and outcome information were retrieved from a prospectively maintained clinical database and validated against the medical records; 241 patients with metastatic breast cancer were included-who had ER+ primary cancer with known Ki67 expression level-and received first-line endocrine therapy for metastatic disease. Patients were assigned to low (< 10 %), intermediate (10-25 %), or high (> 25 %) Ki67 expression groups. Kaplan-Meier survival curves were plotted and multivariate analysis was performed to assess association between clinical and immunohistochemical variables and outcome. The clinical benefit rates were 81, 65, and 55 % in the low (n = 32), intermediate (n = 103), and high (n = 106) Ki67 expression groups (P = 0.001). The median times to progression on first-line endocrine therapy were 20.3 (95 % CI, 17.5-38.5), 10.8 (95 % CI, 8.9-18.8), and 8 (95 % CI, 6.1-11.1) months, respectively (P = 0.0002). The median survival times after diagnosis of metastatic disease were also longer for the low/intermediate compared to the high Ki67 group, 52 versus 30 months (P < 0.0001). In multivariate analysis, high Ki67 expression in the primary tumor remained an independent adverse prognostic factor in metastatic disease (P = 0.001). Low Ki67 expression in the primary tumor is associated with higher clinical benefit and longer time to progression on first-line endocrine therapy and longer survival after metastatic recurrence.
Référence
Breast Cancer Res Treat. 2012 Sep;135(2):619-27