Author(s): MCLAUGHLIN, M., MICHALSKI, M., LEE, J., LEE, C., HARRISON, J., YU, A., SAXTON, J., ROSS, M., MOSKOWITZ, C., JONES, L., SCOTT, J. , Institution: UNIVERSITY OF EDINBURGH, Country: UNITED KINGDOM, Abstract-ID: 333

INTRODUCTION:
Despite potential vascular toxicity of chemotherapy for early-stage breast cancer (EBC) and possible mitigating effects of aerobic training, no study has evaluated effects of chemotherapy or AT across the EBC treatment continuum on vascular endothelial health. Hence, this study aimed to evaluate vascular endothelial function across the early-stage breast cancer (EBC) treatment continuum. Secondary objectives were to evaluate effects of AT on endothelial function, and to explore the association between endothelial function and change in cardiorespiratory fitness (CRF).
METHODS:
A secondary pooled analysis was performed. A total of 161 patients from two randomized AT (16-32 weeks) trials were pooled and categorized into three cross-sectional cohorts: (1) during chemotherapy (initiating (neo)adjuvant chemotherapy; n=53); (2) acute post-treatment (immediately following (neo)adjuvant chemotherapy; n=50); and (3) chronic post-treatment (≥1 to <5 years after completion of primary therapy; n=58). Identical flow mediated dilation (FMD) protocols evaluated endothelial function at baseline (at cohort entry), and post-AT in a subset of n=118 patients randomized to exercise arms. FMD values <5.7% were defined as impaired. Associations between CRF change and (1) baseline FMD and (2) FMD change were quantified via adjusted linear regression.
RESULTS:
In the overall cohort at baseline, median FMD was 8.0% (IQR: 5.7%, 11.4%); n=33 (24%) patients had impaired FMD. No significant differences in FMD or proportion of patients with impaired FMD were observed across cohorts. Among the patients randomized to AT, change in FMD ranged from -9% to 8%, -9% to 6%, and -16% to 13% in the during, acute post-, and chronic post-chemotherapy cohorts, respectively. Neither baseline FMD nor FMD change after AT with associated with CRF change.
CONCLUSION:
In this pooled analysis, endothelial function were not significantly different across the EBC treatment continuum, and did not improve following AT. Additional research is needed to elucidate determinants of interindividual variability in vascular function and exercise response to guide targeted interventions.