CA 27.29 as a tumour marker for risk evaluation and therapy monitoring in patients with primary breast cancer.

CTRC-AACR San Antonio Breast Cancer Symposium: 2008 Abstracts Abstract #2004 Background: Several trials show that the use of tumor markers leads to an early diagnosis of tumor dissemination in breast cancer patients. Whether this improves the prognosis is still under discussion. In the SUCCESS Trial CA27.29 has been examined before and after adjuvant chemotherapy (n=3754). Methods: The SUCCESS Trial compares FEC-Docetaxel (Doc) vs. FEC-Doc-Gemcitabine (Doc-G) regime and two vs. five year treatment with Zoledronat in patients with primary breast cancer (N+ or high risk). CA27.29 has been measured with ST AIA-PACK Ca27.29 reagent using MUC-1 for AIA-600II (Tosoh Bioscience, Tessenderlo, Belgium). The cutoff for positivity of CA27.29 is 24 U/ml. Results: 2669 patients have been examined prospectively before and after chemotherapy. 22% of patients had a marker >24 U/ml (n=587, mean 19.00, range 3.04-410.00) before and 40% (n=1058, mean 23.34, range 2.70-330.76) after chemotherapy. The correlation between both values was significant (p<0.0005). While 17% showed elevated CA27.29 before and after therapy, 5% patients changed from positive to negative for CA27.29 afterwards. 55% were negative before and after therapy whereas 23% became positive after treatment. ![][1] Before treatment the prevalence of elevated CA27.29 was equally distributed between the FEC-Doc and the FEC-Doc-G arm. After treatment 34.1% in the FEC-Doc arm showed an increased level vs. 45.6% in the FEC-Doc-G arm. The correlation analysis showed no significant coherence between hormonal status (ER: p<0.323; PR: p<0.078), HER2/neu status (p<0.308), Grading (p<0.565) and CA27.29 level. However, tumor size (p<0.020) and the nodal status (p<0.022) were significant associated with Ca27.29 levels. Conclusion: These results might indicate a close relation between Ca27.29 and tumour mass at primary diagnosis. Whether this marker will be useful for treatment monitoring will be shown by further follow-up in the Success-trial. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2004. [1]: /embed/graphic-1.gif