Physical Activity, Weight, and Outcomes in Patients Receiving Chemotherapy for Metastatic Breast Cancer (C40502/Alliance).

Background: Obesity and inactivity are associated with increased risk of cancer-related and overall mortality in breast cancer, but there are few data in metastatic disease. Methods: Cancer and Leukemia Group B 40502 was a randomized trial of first-line taxane-based chemotherapy for patients with metastatic breast cancer. Height and weight were collected at enrollment. After 299 patients enrolled, the study was amended to assess recreational physical activity (PA) at enrollment using the Nurses' Health Study Exercise Questionnaire. Associations with progression-free survival (PFS) and overall survival (OS) were evaluated using stratified Cox modeling (strata included hormone receptor status, prior taxane, bevacizumab use, and treatment arm). All statistical tests were 2-sided. Results: A total of 799 patients were enrolled, and at the time of data lock, median follow-up was 60 months. At enrollment, median age was 56.7 years, 73.1% of participants had hormone receptor-positive cancers, 42.6% had obesity, and 47.6% engaged in less than 3 metabolic equivalents of task (MET) hours of PA per week (<1 hour of moderate PA). Neither baseline body mass index nor PA was statistically significantly associated with PFS or OS, although there was a marginally statistically significant increase in PFS (hazard ratio = 0.83, 95% confidence interval = 0.79 to 1.02; P = .08) and OS (hazard ratio = 0.81, 95% confidence interval = 0.65 to 1.02; P = .07) in patients who reported PA greater than 9 MET hours per week vs 0-9 MET hours per week. Conclusions: In a trial of first-line chemotherapy for metastatic breast cancer, rates of obesity and inactivity were high. There was no statistically significant relationship between body mass index and outcomes. More information is needed regarding the relationship between PA and outcomes.

Prognostic variables in low and high risk stage III colon cancers treated in two adjuvant chemotherapy trials.

BACKGROUND: Stratification of patients with stage III colon cancer into low (T1-3N1) and high (T4 and/or N2) risk groups is used to guide the duration of adjuvant chemotherapy. We determined the relative contribution of clinical and molecular features to survival by risk group. MATERIALS & METHODS: Stage III colon cancer (N = 5337) patients from two adjuvant trials of FOLFOX ± cetuximab [N0147 (Alliance), PETACC-8] were risk grouped, then subgrouped by clinical features and molecular variables [KRAS and BRAF/mismatch repair (MMR) combined variable]. Distributions of disease-free survival (DFS), overall survival (OS), and survival after recurrence (SAR) were estimated. In multivariable Cox models, backward elimination was performed for analysis of candidate predictors of outcomes. Relative contributions of model-selected variables to outcomes by risk group were calculated using χ2. RESULTS: Among low risk tumours, mutant KRAS and male gender were significantly associated with poorer OS multivariately. In high risk tumours, significantly poorer OS was observed for right sidedness and for mutant KRAS and BRAFV600E/pMMR, subgroups. Specifically, BRAFV600E/pMMR (OS: HR = 1.75; 95% CI: 1.36-2.24; Padj<.0001) and right- versus left-sidedness were associated with significantly poorer DFS, OS (HR = 1.56; 95% CI: 1.31-1.83; Padj<.0001), and SAR (HR = 1.64; 95% CI: 1.37-1.95; Padj<.0001). Poor prognosis of mutant KRAS for DFS and OS was similar among risk groups. BRAF/MMR and sidedness were associated with poorer SAR in both low and high risk tumours. Age, gender, and KRAS were the top three relative contributors to DFS and OS among low risk tumours; sidedness ranked first for DFS and OS, and second to BRAF/MMR for SAR among high risk tumours. CONCLUSION: Sidedness and BRAF/MMR contributed the most to survival outcomes among high risk tumours and should be interpreted in the context of risk group.