The relation between soluble apoptotic proteins and subclinical cardiotoxicity in adjuvant-treated breast cancer patients

Background: Circulating apoptotic proteins are increased in heart failure patients. We evaluated whether circulating soluble apoptosis-related protein levels change after anthracycline-containing chemotherapy and radiotherapy in relation to cardiac dysfunction or the applied treatment. Patients and Methods: Circulating apoptotic proteins were measured with immunoassay in 40 breast cancer patients following surgery (T0), one month (T1) and one year (T2) after epirubicin-based chemotherapy. Standard-dose (n=21) or high-dose (n=19) myeloablative chemotherapy, preceded irradiation and tamoxifen. Circulating apoptotic proteins were compared with previous cardiac evaluations. Results: Soluble tumor necrosis factor receptor 1 (+30%), 2 (+43%) and Fas (+40%) were transiently increased at T-1 compared to T-0, whereas Fas ligand (-64%) was transiently decreased, especially in the high-dose group. Apoptosis markers were not associated with cardiac dysfunction. Conclusion: Significant, but transient changes in soluble apoptotic protein levels were observed, particularly after high-dose chemotherapy. No relation was found between apoptosis-related proteins and cardiotoxicity.