The Cardiac Markers and Oxidative Stress Parameters in Advanced Non-Small Cell Lung Cancer Patients Receiving Cisplatin-Based Chemotherapy

INTRODUCTION: Cardiotoxicity is a well known long-term consequence of lung cancer chemotherapy, however little is known about early subclinical changes in cardiac function. AIM: The goal of the study was to assess early cardiotoxic effects of cisplatin-containing chemotherapy in stage III and IV lung cancer patients, measuring serum levels of selected cardiac markers in relation to oxidant effects. METHODS: We quantified the immediate impact of chemotherapy on cardiac troponin T (TnT), creatine kinase-myocardial band (CK-MB) and N- terminal pro-brain natriuretic peptide (NT-proBNP) in blood samples obtained from 12 non-small cell lung cancer (NSCLC) patients. All markers were measured using commercially available immunoassays. To investigate the oxidant effects of cisplatin-containing chemotherapy, we evaluated reduced glutathione (GSH), nitrite (NO2), derivatives of reactive oxygen metabolites (d-ROMs) and thiols (SH). Samples were collected prior to chemotherapy and 1 day after the first cycle of cisplatin administration. RESULTS: Chemotherapy did not cause statistically significant elevations in serum CK-MB. Serum TnT levels were undetectable at both time points in 11 out of 12 patients with a threshold of 0.01 ng/ml. In the single patient with undetectable TnT at the baseline, after the first infusion TnT level reversibly rose to 0.03 ng/ml. The pre-treatment value of NT-proBNP was slightly elevated in 7 out of 12 lung cancer patients. In 1 case NT-proBNP level significantly increased after chemotherapy (from 221.8 to 1489.0 pg/ml p<0.001), in the remaining 11 patients it was stable Cisplatin-based combination chemotherapy induced significant nitrite production in 5 patients (p<0.05). The other measured oxidative stress parameters remained unchanged after the first infusion. CONCLUSION: This pilot study demonstrated occasional elevations of cardiac biomarkers during cisplatin administration. Administration of cisplatin-containing chemotherapy caused significant nitroxidative stress in some patients. The relevance of cardiovascular complications in cancer patients and identification individual risk factors of developing cardiovascular toxicity merit further evaluation.