Excess Body Weight Increases Risk of Second Primary Cancers in cancer Survivors: JAMA

A new study published in the Journal of American Medical Association found that cancer survivors with overweight or obesity are at significantly higher risk of developing second primary malignant cancers, which are associated with excess body weight. This research utilized data from the Cancer Prevention Study II Nutrition cohort and highlighted the need for stronger weight management initiatives in cancer survivorship care.

This study investigated the relationship between body mass index (BMI) and the likelihood of developing a second primary cancer. The study drew on data from 26,894 participants across 21 U.S. states where these individuals had been diagnosed with a first primary non-metastatic invasive cancer between 1992 and 2015. Their health was tracked through biennial surveys until 2017 and the analysis of this study was completed between September 2023 and March 2024.

The focus of the study was to assess how the BMI of the participants at the time of their first cancer diagnosis affected their risk of developing a second primary cancer. The BMI of the participants was calculated based on self-reported height and weight. The average age at the time of the first cancer diagnosis was 72.2 years, and the average time to diagnosis from when the BMI was calculated was 1.7 years.

The results showed that during the median follow-up period of 7.9 years, 13.9% (3,749) of participants were diagnosed with a second primary cancer. Also, 33.2% (1,243) of these cases were obesity-related cancers. The data revealed a clear connection between higher BMI and the risk of developing any second primary cancer.

The participants with a BMI classified as overweight (BMI 25 to <30) had a 15% higher risk of a second cancer, while the ones classified as obese (BMI ≥30) faced a 34% increased risk when compared to the individuals with a normal BMI (18.5 to <25). The risk of obesity-related second cancers was even more pronounced. Overweight individuals had a 40% higher risk of developing an obesity-related second cancer, while the individuals with obesity had a sharp 78% increased risk.

The findings of this study emphasize the need for greater attention to weight management among cancer survivors. Given the high prevalence of overweight and obesity in this population, targeted interventions could significantly reduce the risk of second cancers. This research suggest that both clinicians and cancer survivors need to be more aware of the potential for second cancers and promote guidelines for maintaining a healthy weight during survivorship care. These findings addresses obesity as a significant risk factor in cancer recurrence by urging more comprehensive weight management strategies in cancer care plans.

Source:

Bodelon, C., Sung, H., Mitchell, E. L., Deubler, E. L., Newton, C. C., Jemal, A., Teras, L. R., & Patel, A. V. (2024). Excess body weight and the risk of second primary cancers among cancer survivors. JAMA Network Open, 7(9), e2433132. https://doi.org/10.1001/jamanetworkopen.2024.33132