Predictors for Pancreatic Cancer Diagnosis Following New-Onset Diabetes Mellitus.

OBJECTIVES: New-onset diabetes mellitus (NODM) in adults is often an early manifestation of pancreatic cancer (PaCa), but the incidence of PaCa in this cohort is rather low. We evaluated whether combining other patient factors such as age, smoking history, the absence of obesity, the presence of chronic pancreatitis (CP), and gallstone disease can result in a more enriched cohort.

METHODS: After a washout period of 2 years to exclude pre-existing PaCa or DM, 507,378 non-diabetic patients in the veterans' administration healthcare system were identified. Patients <40 years (n=54,465) and those with PaCa diagnosed before the diagnosis of diabetes (n=22) were excluded. A total of 452,804 veterans were followed for development of DM or PaCa.

RESULTS: 73,811 patients (16.3%) developed NODM during the follow-up period. One hundred and eighty-three NODM patients (0.25%) were diagnosed with PaCa within 3 years. In comparison, 434 of 378,993 remaining patients (0.11%) developed PaCa in 3 years following inclusion into the study [relative risk (RR)=2.27, 95% confidence intervals (CI) 1.96, 2.63; P<0.0001]. The risk of PaCa diagnosis was higher among patients who were non-obese (RR=1.51), were ≥65 years old (RR=2.01), were heavy smokers (RR=1.55), and had a history of CP (RR=4.72) or gallstone disease (RR=2.02). Using a combination of these risk factors in NODM patients resulted in up to 0.72% three-year risk of PaCa but captured only 17% of patients with PaCa.

CONCLUSIONS: Based on our findings, the likelihood of PaCa in adults with NODM even after adjusting for other potential risk factors for PaCa including age, body mass index, smoking, gallstones, and CP is probably not high enough to recommend routine evaluation for all these patients for underlying PaCa.