Body Mass Index and Weight Loss in Metastatic Colorectal Cancer in CALGB (Alliance)/SWOG 80405
Menée à partir de données portant sur 2 323 patients atteints d'un cancer colorectal métastatique et inclus dans un essai de phase III, cette étude évalue l'association entre l'indice de masse corporelle et la perte de poids avant l'inclusion dans l'essai et la survie globale ou la survie sans progression
In non-metastatic colorectal cancer, overweight and mild-to-moderately obese patients experience improved outcomes compared to other patients. Obesity’s influence on advanced or metastatic colorectal cancer (mCRC) is relatively unexplored.We conducted a prospective BMI companion study in CALGB (now Alliance)/SWOG 80405, a phase III mCRC treatment trial. BMI was measured at trial registration. Primary and secondary endpoints were overall and progression-free survival, respectively. To minimize confounding by poor and rapidly declining health, we used Cox proportional hazards regression to adjust for known prognostic factors, comorbidities, physical activity, and weight loss during the 6 months prior to study entry. We also examined weight loss prior to enrollment as an independent predictor of patient outcome. All statistical tests were two-sided.Among 2,323 patients with mCRC, there were no statistically significant associations between BMI and overall or progression-free survival (adjusted Ptrend =.12 and .40, respectively). Weight loss during the 6 months prior to study entry was associated with shorter overall and progression-free survival; compared to individuals with stable weight ±4.9%, individuals with weight loss >15% experienced an adjusted hazard ratio of 1.52 for all-cause mortality (95% confidence interval 1.26 to 1.84, Ptrend <.001) and of 1.23 for disease progression or death (95% confidence interval 1.02 to 1.47, Ptrend =.006).In this prospective study of patients with mCRC, BMI at time of first-line chemotherapy initiation was not associated with patient outcome. Weight loss prior to study entry was associated with increased risk of patient mortality and disease progression.
JNCI Cancer Spectrum , article en libre accès, 2019