Expression of Cytokeratin - 18 in Serum as a Biomarker of Apoptosis & Necrosis in Carcinoma Breast

Abstract

Background: Cytokeratin expression is helpful in differentiating between specific breast cancer subtypes and as prognostic indicator. Objectives: To compare the cytokeratin-18 levels between breast cancer and healthy control. To compare cytokeratin-18 levels before and after neo-adjuvant chemotherapy (NAC) and to correlate cytokeratin-18 levels of pre and post chemotherapy with the percentage response to chemotherapy as evaluated by the RECIST criteria. Methods: Thirty patients of histologically confirmed invasive breast carcinoma and ten healthy individuals were taken as controls. The estimation of cytokeratin-18 was done at presentation and after two cycles of NAC. The change in level of serum cytokeratin-18 levels following two cycles of chemotherapy has been correlated with the RECIST criteria of response to chemotherapy. Results: Mean age of the patients was 48.73 years (range 28-80 years). The mean cytokeratin-18 level in carcinoma breast patient pre-treatment was 156.27 IU/L and in control group was 279.30 IU/L. The mean Cytokeratin 18 levels in patients before and after chemotherapy was 156.27 IU/L and 181.77 IU/L respectively (p<0.05). The average diameter of tumor before and after chemotherapy was 5.33 and 3.73 cm respectively. On correlation of percentage change of Cytokeratin 18 levels before and after chemotherapy and response to chemotherapy as evaluated by the RECIST criteria the following result was obtained: complete response (n=2): 76% rise of CK-18, partial response (n=21): 24% rise of CK-18, stable disease (n=5): 22% decline of CK-18, progressive disease (n=2), 21% decline of CK-18. Conclusion: The expression of cytokeratin-18 is a useful biomarker in breast cancer patient. Serum levels of CK-18 can be used to judge the efficacy of neo-adjuvant chemotherapy. Depending on post chemotherapy changes of CK-18 levels, the most appropriate chemotherapy regimen can be selected for individual patients.