Abstract P1-15-03: Association between exercise, pathological complete response, and treatment tolerability in patients receiving neoadjuvant chemotherapy for operable breast cancer: Results from the CANTO study
Authors: Baker JL , Di Meglio A , El Mouhebb M , Iyengar NM , Michiels S , Cottu P , Lerebours F , Coutant C , Lesur A , Tredan O , Soulie P , Vanlemmens L , Jouannaud C , Levy C , Everhard S , Martin A-L , Arveux P , Fabrice A , Vaz Luis I , Jones LW 
Published: May 2019

Background: Randomized trials, although not all, suggest exercise therapy improves treatment completion rates / relative dose intensity in patients with early-stage breast cancer receiving adjuvant chemotherapy (CT). In addition, preclinical studies show that exercise therapy adds to the antitumor activity of standard CT in murine models of breast cancer. We evaluated the association between exercise and pathologic complete response (pCR) rate (i.e., ypT0ypN0) in patients receiving neoadjuvant CT for operable breast cancer.

Methods: Using a prospective design, patients with stage I-III breast cancer receiving anthracycline-taxane (± trastuzumab) neoadjuvant CT participating in a multicenter, national cohort study in France (CANTO, NCT01993498) completed questionnaire assessing self-reported exercise behavior (GPAQ 16). Multivariate logistic models were performed to determine the relationship between pre-CT exercise exposure (total MET-h/wk categorized into the proportion of patients meeting WHO exercise guidelines, the equivalent of ≥10 MET-h/wk), pCR rates, CT± trastuzumab dose reductions, delays, treatment completion or interruptions for the overall cohort and on the basis of clinical subtype.

Results: Between March, 2012 to December, 2014, a total of 989 patients participating in CANTO received neoadjuvant CT and completed GPAQ 16. Here we present interim analyses on 608 patients. Fifty-four percent of patients engaged on of ≥10 MET-h/wk prior to CT administration. In multivariable analysis for the overall cohort, exercise exposure was not associated with higher pCR (p=0.69). The pCR rate was 27.7% for patients reporting &lt;10 MET h/wkcompared with 28.0% for those reporting ≥ 10 MET-h/wk (OR, 1.02; 95% CI, 0.71-1.45). Stratification analyses indicated no differences on the basis of clinical subtype for hormone receptor (HR) positive/HER2 negative (&lt;10 MET h/wk: 15.1% vs. ≥ 10 MET h/wk: 16.5%; OR, 0.95, 0.41-2.16); HER2 positive (&lt;10 MET h/wk: 38.1% vs. ≥ 10 MET h/wk: 32.5%; OR, 0.62, 0.28-1.35); or triple-negative disease (&lt;10 MET h/wk: 33.3% vs. ≥ 10 MET h/wk: 36.7%; OR, 1.04, 0.52-2.10). Rates of CT dose reductions (&lt;10 MET h/wk: 16.1% vs. ≥ 10 MET h/wk: 18.3%), CT dose delays (&lt;10 MET h/wk: 19.9% vs. ≥ 10 MET h/wk: 19.8%), CT completion (&lt;10 MET h/wk: 12.03% vs. ≥ 10 MET h/wk: 11.45%) trastuzumab interruptions (&lt;10 MET h/wk: 9.01% vs. ≥ 10 MET h/wk: 7.95%) were also not different on the basis of exercise exposure.

Conclusion: On the basis of interim analyses, higher pretreatment exercise exposure is not associated with higher clinical response or treatment tolerability in breast cancer patients receiving uniform conventional neoadjuvant CT. Full results will be presented at the meeting.

Citation Format: Baker JL, Di Meglio A, El Mouhebb M, Iyengar NM, Michiels S, Cottu P, Lerebours F, Coutant C, Lesur A, Tredan O, Soulie P, Vanlemmens L, Jouannaud C, Levy C, Everhard S, Martin A-L, Arveux P, Fabrice A, Vaz Luis I, Jones LW. Association between exercise, pathological complete response, and treatment tolerability in patients receiving neoadjuvant chemotherapy for operable breast cancer: Results from the CANTO study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-15-03.