New-Onset Type 2 Diabetes Tied to Higher Risk of Specific Obesity-Related Cancers
New data to be presented at ECO 2025 shows new-onset T2D is linked to increased risk of liver, pancreatic, and bowel cancers, but not endometrial or post-menopausal breast cancer.
Andrew Renehan, PhD
Photo courtesy of The Christie NHS Foundation Trust
New research reveals that a new diagnosis of type 2 diabetes (T2D) is associated with an increased risk of developing certain obesity-related cancers (ORCs)—most notably liver, pancreatic, and bowel cancer—while showing no significant link to others, such as endometrial or postmenopausal breast cancer.1
Data from the new study will be presented at this year’s European Congress on Obesity (ECO), taking place May 11-14 in Malaga, Spain.
An estimated 589 million people aged 20 to 79 years worldwide have diabetes, and alarmingly, more than 250 million of them remain undiagnosed, according to the 11th edition of the International Diabetes Federation’s (IDF’s) Diabetes Atlas.2 Additionally, the IDF noted that nearly 1 in 8 adults are at high risk of developing T2D. This widespread underdiagnosis carries serious health consequences, leaving millions at increased risk for severe complications and premature death.
Previous studies have suggested an association between T2D and an elevated risk of several ORCs, but causality has been unclear due to confounding factors such as shared risk factors (eg, obesity), immortal time bias, and detection-time bias. To resolve these issues, researchers conducted a matched cohort control study within the UK Biobank, focusing on participants with new-onset T2D. They compared these individuals with controls matched on body mass index (BMI), age, and sex.1
The primary outcome of the study was the incidence of ORCs, including liver, pancreatic, bowel, post-menopausal breast, endometrial, kidney, esophageal, stomach, multiple myeloma, gallbladder, thyroid, meningioma, and ovarian cancers. Investigators also examined the risk of site-specific cancers where case numbers are allowed. Statistical models adjusted for alcohol consumption, smoking, and increased surveillance after T2D diagnosis were used to determine the increased risk of cancer in individuals with T2D.1
The study included 23 750 participants with T2D and 71 123 matched controls. Over a median follow-up of 5 years, there were 2431 new primary cancers among participants with T2D and 5184 among controls. The analysis revealed that new-onset T2D was associated with a 48% increased risk of ORCs in men and a 24% increased risk in women, independent of BMI. However, there were no significant associations with certain site-specific cancers, such as endometrial and post-menopausal breast cancer in women.1
The study found that new-onset T2D was particularly linked to an increased risk of developing several cancers. For bowel cancer, the risk increased by 27% in men and 34% in women. Pancreatic cancer risk rose by 74% in men and nearly doubled in women. Liver cancer risk was significantly higher in both men (nearly quadrupled) and women (nearly fivefold).1
“At this stage we are unsure whether these differences in men and women are due to a sex-dependent biological pathway such as hormone levels, insulin sensitivity, body fat composition, or due to a simple difference in the number of cancers found in men and women within UK Biobank by chance,” investigators stated in a press release.1
In conclusion, researchers suggest that while new-onset T2D is associated with an increased risk for some OACs, the mechanisms behind this connection remain unclear. They speculate that hyperinsulinemia, a key feature of T2D, may play a central role in cancer development. “Hyperinsulinemia has the strongest evidence for a plausible mechanism due to its ability to stimulate cell growth and proliferation,” they stated.1
“Having accounted for key biases found in previous research in this field, and confounding (by adjusting for BMI, smoking, alcohol, and detection-time bias), our findings indicate that new-onset T2DM is associated with some but not all site-specific obesity-related cancers,” study authors concluded.1 “In turn, the pathways through which T2DM may affect obesity-related cancer require further investigation.”
References:
1. Study of UK biobank reveals link between new-onset type 2 diabetes and some but not all obesity-related cancers. News release. European Association for the Study of Obesity. March 22, 2025. Accessed April 24, 2025. https://www.eurekalert.org/news-releases/1077674
2. Over 250 million people worldwide unaware they have diabetes, according to new research from the International Diabetes Federation (IDF). News release. International Diabetes Federation. April 7, 2025. Accessed April 24, 2025. https://www.prnewswire.com/news-releases/over-250-million-people-worldwide-unaware-they-have-diabetes-according-to-new-research-from-the-international-diabetes-federation-idf-302419968.html
