Finding is yet another reason to maintain a healthy weight, experts say
WebMD News from HealthDay
By Alan Mozes
Health Day Reporter
TUESDAY, Sept. 30, 2014 (HealthDay News) -- Colon cancer patients who are overweight or obese when diagnosed appear to face a slightly higher risk for developing a second weight-related cancer, new research suggests.
The finding didn't speak to the risk of colon cancer recurrence, only the potential for developing other cancers associated with obesity.
"We found that colorectal cancer survivors who reported being overweight or obese prior to diagnosis had a modestly increased risk of developing an obesity-related second cancer compared to [cancer survivors] who reported a normal weight," said study lead author Todd Gibson, who conducted his research while a fellow with the U.S. National Cancer Institute.
A higher obesity-driven risk was identified for kidney, pancreatic, esophageal and endometrial cancers, as well as for postmenopausal breast cancer among female colorectal cancer patients.
Gibson, now an assistant faculty member at St. Jude Children's Research Hospital in Memphis, and his colleagues discussed the findings in the Sept. 29 online edition of the Journal of Clinical Oncology.
The authors noted that roughly 1.1 million Americans are living with colon cancer, and obesity has long been cited as a contributing risk factor for the disease.
However, in most cases colorectal cancer has a relatively high survival rate, with roughly 70 to 90 percent of patients living to the five-year mark following their diagnosis.
To assess how obesity might affect additional cancer risk post-survival, the research team focused on nearly 12,000 colon cancer survivors who were about age 69 on average when first diagnosed.
Patient weight had been assessed prior to their initial diagnosis by means of a body mass index calculation. BMI readings are based on height and weight.
In all, 44 percent of the patients were deemed overweight (a BMI between 25 and 29), while one-quarter were obese (a BMI of 30 or more).
When compared with colorectal cancer survivors who had been at "normal" weight at diagnosis, those who had been overweight or obese faced a greater risk for developing a second obesity-related cancer down the road.
However, the team stressed that the actual risk that an obese or overweight colon cancer survivor would develop a secondary cancer remained low, even if their relative risk was almost double that of normal-weight survivors.
Also, the risk for developing one of the obesity-related cancers was actually no higher among obese and overweight colon cancer survivors than it was for obese and overweight members of the general public who'd never had colon cancer.
In other words, the smoking gun appears to be obesity itself, rather than a prior history of cancer.
"The implication," said Gibson, "is that maintaining a healthy weight is important for cancer prevention in colorectal cancer survivors, just as it is in the general population. [So] our results further emphasize the importance of existing guidelines recommending healthy weight for survivors."
source : Obesity Tied to Higher Cancer Risk for Colon Cancer Survivors
