HealthDay News – Patients with colorectal cancer (CRC) who are overweight or obese when diagnosed appear to face a slightly higher risk for developing a second related cancer that is related to their weight, according to research published in the Journal of Clinical Oncology.
The findings did not address the rise of CRC recurrence, but only the potential for developing other cancers associated with obesity.
To assess how obesity might affect additional cancer risk post-survival, Todd Gibson, PhD, and colleagues at the United States National Cancer Institute, focused on 11,598 CRC aged 69 years on average when first diagnosed. The weight of patients in the study had been assessed before their initial diagnoses by means of a body mass index (BMI) calculation. In all, 44% of the patients were deemed overweight (BMI, 25 to 29 kg/m²), whereas one-quarter were obese (BMI, ≥30 kg/m²).
Compared with CRC survivors who had been at normal weight at diagnosis, those who had been overweight or obese faced a greater risk for developing a second weight-related cancer later in life.
A higher weight-driven risk was identified for kidney, pancreatic, esophageal, and endometrial cancers, as well as for postmenopausal breast cancer among female CRC patients. However, the team stressed that the actual risk that an obese or overweight CRC survivor would develop a second type cancer remained low, even if their relative risk was almost double that of normal-weight survivors.
“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,” noted the researchers.