Background Exercise training (ET) has been shown to mitigate cardiotoxicity of anthracycline-based chemotherapies (AC) in animal models. Data from randomized controlled trials in patients with cancer are sparse. Methods Patients with breast cancer or lymphoma receiving AC were recruited from four cancer centres and randomly assigned to three months supervised ET during (EXduringAC) or after (EXpostAC) AC. All patients were counselled on physical activity (PA) and PA was objectively measured with an activity tracker with PA feedback option. Primary endpoint was change in left ventricular global longitudinal strain (GLS) between baseline and AC completion (AC-end) assessed by transthoracic 2D echocardiography. Secondary endpoints were change in high sensitivity Troponin T (hsTnT) and NT-pro-brain natriuretic peptide (NT-proBNP) between baseline and AC-end. Exploratory analyses were performed at 6 months (follow-up). Primary and exploratory analysis were performed by linear mixed models and robust linear models, respectively. Results One-hundred-and-forty-three patients were eligible for the study. Fifty-seven patients (median age 47 [1st and 3rd quartiles 38, 57] years; 95% women) consented to participate, of whom 28 and 29 patients were randomized to the EXduringAC and EXpostAC group, respectively. GLS deteriorated in both study groups from baseline to AC-end with 7.4% and 6.2% relative increase in EXduringAC and EXpostAC, respectively, and hsTnT and NT-proBNP significantly increased in both groups, without difference between groups for any parameter. Duration of moderate-to-vigorous PA (MVPA) was also similar between groups with a median of 33 [26, 47] min/day and 32 [21, 59] min/day in the EXduringAC and EXpostAC group, respectively. In the robust linear model including the pooled patient population, MVPA was significantly associated with a more negative GLS and lesser increase in hsTnT. Conclusion In physically active patients with cancer receiving AC, supervised ET during chemotherapy was not superior to PA advice and tracker monitoring only to mitigate cardiotoxicity. Objectively measured PA was inversely related to markers of LV function and myocardial injury.

The authors have declared no competing interest.

Clinical Trials.gov: NCT03850171

The study was funded by a Swiss Cancer Research Grant to the CAPRICE study under grant number HSR-4360-11-2017.

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