Add liver cancer to the risks associated with type 2 diabetes (T2D) and obesity. That’s the conclusion of a new study published today in the journal Cancer Research, the official publication of the American Association of Cancer Research (AACR).
Over the past 4 decades, rates of liver cancer have tripled alongside rising obesity rates and increased incidence of T2D, prompting leaders at AACR and the National Cancer Institute to investigate a connection between this type of cancer and metabolic disorders.
Led by Peter Campbell, PhD, strategic director for Digestive System Cancer Research at AACR, researchers pooled data from 14 prospective studies involving 1.57 million participants. All were asked about height, weight, alcohol and tobacco use, and other factors associated with cancer risk.
No one had cancer at the time of enrollment, while 6.5% of the participants already had T2D. Over time, 2162 participants developed liver cancer. The researchers compared rates of liver cancer among those with and without T2D and obesity, and found that as body mass index (BMI) increased, so did cancer risk.
For every 5 kg/m2 increase in BMI, there was a 38% increased risk of liver cancer in men and a 25% increased risk in women. The risk of liver cancer rose 8% for every 5 cm increase (about 2 inches) in waist circumference.
Those with T2D were 2.61 times more likely to be diagnosed with liver cancer, and risks rose with BMI (after controlling for alcohol and tobacco use and race).
“This is yet another reason to maintain a body weight in the normal range for your height,” said Campbell. By CDC standards, a normal BMI is between 18.5 and 24.9 kg/m2; from 25 to 29.9 is considered overweight, while 30 and above is considered obese.
Campbell said the findings are consistent with other data that suggest the link between liver cancer and metabolic disorders. “Liver cancer isn’t simply related to excess alcohol intake and viral hepatitis infection,” he said.
Co-author Katherine A. McGlynn, PhD, MPH, of the National Cancer Institute echoed the public health implications of the study. “These results are very important because obesity and diabetes, unfortunately, are common conditions in the population,” she said. Although conditions like hepatitis B virus or hepatitis C virus are also associated with liver cancer, these are far less common.
Campbell PT, Newton CC, Freedman ND, et al. Body mass index, waist circumference, diabetes, and risk of liver cancer for U.S. adults. Cancer Res. 2016; DOI: 10.1158/0008-5472.CAN-16-0787.