BACKGROUND: Ki-67 expression has gained attention as a breast cancer prognostic factor, however its significance in the remaining malignant cells after neoadjuvant chemotherapy (NAC) has been rarely examined. This investigation, extension and analysis of a previously reported cohort of patients, evaluates the significance of Ki-67 and estrogen receptor (ER) expression after NAC in LABC (locally advanced breast cancer). PATIENTS AND METHODS: clinical stage, tumor size, clinical and pathological lymph node involvement, Ki-67, ER, progesterone receptor (PgR), HER2 expression, grading and clinical response were evaluated before and after NAC in 110 patients with LABC. Ki-67 expression was assessed both in pre and post-therapy histological samples, using >15% positive cells as cut-off value to distinguish high from low Ki-67 expressing tumors. RESULTS: six patients (5.45%) attained pCR after NAC. A significant relationship between elevated post-CT Ki-67 and ER expression was showed at Cox multivariate analysis of disease free survival (DFS). On univariate analysis high post-chemotherapy Ki-67 and ER status were associated with worse survival; at multivariate model included these results were confirmed. Based on these two parameters, a prognostic model identified two different groups: low risk (low postchemotherapy Ki-67 and ER positive, or either high post-chemotherapy Ki-67 or ER negative), and high risk (high post-chemotherapy Ki-67 and ER negative). The low risk group showed a good prognosis (median OS still not reached), while the high risk group had a worse OS (median 41 months). CONCLUSIONS: Ki-67 value after NAC and ER status could predict a worse prognosis among LABC patients treated with NAC.
BACKGROUND: Ki-67 expression has gained attention as a breast cancer prognostic factor, however its significance in the remaining malignant cells after neoadjuvant chemotherapy (NAC) has been rarely examined. This investigation, extension and analysis of a previously reported cohort of patients, evaluates the significance of Ki-67 and estrogen receptor (ER) expression after NAC in LABC (locally advanced breast cancer). PATIENTS AND METHODS: clinical stage, tumor size, clinical and pathological lymph node involvement, Ki-67, ER, progesterone receptor (PgR), HER2 expression, grading and clinical response were evaluated before and after NAC in 110 patients with LABC. Ki-67 expression was assessed both in pre and post-therapy histological samples, using >15% positive cells as cut-off value to distinguish high from low Ki-67 expressing tumors. RESULTS: six patients (5.45%) attained pCR after NAC. A significant relationship between elevated post-CT Ki-67 and ER expression was showed at Cox multivariate analysis of disease free survival (DFS). On univariate analysis high post-chemotherapy Ki-67 and ER status were associated with worse survival; at multivariate model included these results were confirmed. Based on these two parameters, a prognostic model identified two different groups: low risk (low postchemotherapy Ki-67 and ER positive, or either high post-chemotherapy Ki-67 or ER negative), and high risk (high post-chemotherapy Ki-67 and ER negative). The low risk group showed a good prognosis (median OS still not reached), while the high risk group had a worse OS (median 41 months). CONCLUSIONS: Ki-67 value after NAC and ER status could predict a worse prognosis among LABC patients treated with NAC.
Authors: Samuel C Y Leung; Torsten O Nielsen; Lila Zabaglo; Indu Arun; Sunil S Badve; Anita L Bane; John M S Bartlett; Signe Borgquist; Martin C Chang; Andrew Dodson; Rebecca A Enos; Susan Fineberg; Cornelia M Focke; Dongxia Gao; Allen M Gown; Dorthe Grabau; Carolina Gutierrez; Judith C Hugh; Zuzana Kos; Anne-Vibeke Lænkholm; Ming-Gang Lin; Mauro G Mastropasqua; Takuya Moriya; Sharon Nofech-Mozes; C Kent Osborne; Frédérique M Penault-Llorca; Tammy Piper; Takashi Sakatani; Roberto Salgado; Jane Starczynski; Giuseppe Viale; Daniel F Hayes; Lisa M McShane; Mitch Dowsett Journal: NPJ Breast Cancer Date: 2016-05-18