TY - JOUR
T1 - Body mass index and risk of second obesity-associated cancers after colorectal cancer
T2 - A pooled analysis of prospective cohort studies
AU - Gibson, Todd M.
AU - Park, Yikyung
AU - Robien, Kim
AU - Shiels, Meredith S.
AU - Black, Amanda
AU - Sampson, Joshua N.
AU - Purdue, Mark P.
AU - Beane Freeman, Laura E.
AU - Andreotti, Gabriella
AU - Weinstein, Stephanie J.
AU - Albanes, Demetrius
AU - Fraumeni, Joseph F.
AU - Curtis, Rochelle E.
AU - Berrington De Gonzalez, Amy
AU - Morton, Lindsay M.
N1 - Publisher Copyright:
© 2014 by American Society of Clinical Oncology.
PY - 2014/12/10
Y1 - 2014/12/10
N2 - Purpose: To determine whether prediagnostic body mass index (BMI) is associated with risk of second obesity-associated cancers in colorectal cancer (CRC) survivors, and whether CRC survivors have increased susceptibility to obesity-associated cancer compared with cancer-free individuals. Patients and Methods: Incident first primary CRC cases (N = 11,598) were identified from five prospective cohort studies. We used Cox proportional hazards regression models to examine associations between baseline (prediagnostic) BMI and risk of second obesity-associated cancers (postmenopausal breast, kidney, pancreas, esophageal adenocarcinoma, endometrium) in CRC survivors, and compared associations to those for first obesity-associated cancers in the full cohort. Results: Compared with survivors with normal prediagnostic BMI (18.5-24.9 kg/m2), those who were overweight (25-29.9 kg/m2) or obese (30+ kg/m2) had greater risk of a second obesity-associated cancer (n = 224; overweight hazard ratio [HR], 1.39; 95% CI, 1.01 to 1.92; obese HR, 1.47; 95% CI, 1.02 to 2.12; per 5-unit change in BMI HR, 1.12; 95% CI, 0.98 to 1.29). The magnitude of risk for developing a first primary obesity-associated cancer was similar (overweight HR, 1.18; 95% CI, 1.14 to 1.21; obese HR, 1.61; 95% CI, 1.56 to 1.66; per 5-unit change in BMI HR, 1.23; 95% CI, 1.21 to 1.24). Before diagnosis CRC patients were somewhat more likely than the overall cohort to be overweight (44% v 41%) or obese (25% v 21%). Conclusion: CRC survivors who were overweight or obese before diagnosis had increased risk of second obesity-associated cancers compared with survivors with normal weight. The risks were similar in magnitude to those observed for first cancers in this population, suggesting increased prevalence of overweight or obesity, rather than increased susceptibility, may contribute to elevated second cancer risks in colorectal cancer survivors compared with the general population. These results support emphasis of existing weight guidelines for this high-risk group.
AB - Purpose: To determine whether prediagnostic body mass index (BMI) is associated with risk of second obesity-associated cancers in colorectal cancer (CRC) survivors, and whether CRC survivors have increased susceptibility to obesity-associated cancer compared with cancer-free individuals. Patients and Methods: Incident first primary CRC cases (N = 11,598) were identified from five prospective cohort studies. We used Cox proportional hazards regression models to examine associations between baseline (prediagnostic) BMI and risk of second obesity-associated cancers (postmenopausal breast, kidney, pancreas, esophageal adenocarcinoma, endometrium) in CRC survivors, and compared associations to those for first obesity-associated cancers in the full cohort. Results: Compared with survivors with normal prediagnostic BMI (18.5-24.9 kg/m2), those who were overweight (25-29.9 kg/m2) or obese (30+ kg/m2) had greater risk of a second obesity-associated cancer (n = 224; overweight hazard ratio [HR], 1.39; 95% CI, 1.01 to 1.92; obese HR, 1.47; 95% CI, 1.02 to 2.12; per 5-unit change in BMI HR, 1.12; 95% CI, 0.98 to 1.29). The magnitude of risk for developing a first primary obesity-associated cancer was similar (overweight HR, 1.18; 95% CI, 1.14 to 1.21; obese HR, 1.61; 95% CI, 1.56 to 1.66; per 5-unit change in BMI HR, 1.23; 95% CI, 1.21 to 1.24). Before diagnosis CRC patients were somewhat more likely than the overall cohort to be overweight (44% v 41%) or obese (25% v 21%). Conclusion: CRC survivors who were overweight or obese before diagnosis had increased risk of second obesity-associated cancers compared with survivors with normal weight. The risks were similar in magnitude to those observed for first cancers in this population, suggesting increased prevalence of overweight or obesity, rather than increased susceptibility, may contribute to elevated second cancer risks in colorectal cancer survivors compared with the general population. These results support emphasis of existing weight guidelines for this high-risk group.
UR - http://www.scopus.com/inward/record.url?scp=84918552043&partnerID=8YFLogxK
U2 - 10.1200/JCO.2014.56.8444
DO - 10.1200/JCO.2014.56.8444
M3 - Article
C2 - 25267739
AN - SCOPUS:84918552043
SN - 0732-183X
VL - 32
SP - 4004
EP - 4011
JO - Journal of Clinical Oncology
JF - Journal of Clinical Oncology
IS - 35
ER -