P4-09-05: CA15-3 Adds Prognostic Information in “Luminal” Type Breast Cancer – A Single Center Experience Evaluating 700 Patients with a Median Follow-Up of 5 Years.

Background: Prognostic markers are essential for the decision about individual therapy for patients with newly diagnosed breast cancer. Biological meaningful cancer types are revealed by gene expression analysis. Steroid hormone receptor (HR) and HER2 status of the tumor by immunohistochemistry (IHC) are more easily available and predominantly resemble these cancer types. The “luminal” type as HR pos. and HER2 neg., the “luminalHER2” type as HR pos. and HER2 pos., the “HER2” type as HR neg. and HER2 pos. and the “triple neg.” type as HER neg. and HER2 ***neg.. We evaluated preoperative serum CA 15–3 and CEA within IHC-cancer types and outcome using our own cohort from 1999–2010. Material and Methods: Since 1999 all patients with breast cancer were entered in our tumor registry. Patients were treated by surgery and adjuvant therapy according to national guidelines (www.ago-online.de). Data was entered into SPSS by a specially trained study nurse. Follow-up was obtained yearly using our own out-patient clinic, information from general practitioners and the general cancer registry. Informed consent was taken from the patients at time of diagnosis. CA 15–3 and CEA were defined elevated if above 25 U/ml or 4,6 μg/l respectively. Results: Preoperative serum CA15-3 available for 1149 patients. Patients with elevated results showed a reduced 5year disease-free survival (DFS) of 74.4% as compared to 84.7% (p Discussion: Decision on adjuvant therapy is increasingly based on tumor biology. Particularly, in “luminal” tumors additional prognostic information is needed to decide on adjuvant chemotherapy. CA15-3 may be an easily available, independent marker to identify patients with a higher risk of recurrence within this group. Prospective validation and comparison to molecular typing is needed. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-09-05.