The odds of neoplasia in dogs with and without diabetes mellitus

BACKGROUND: Increased risk of neoplasia in humans with diabetes mellitus (DM) is well documented. It is unknown if dogs with DM have increased risk of neoplasia. OBJECTIVE: Determine if dogs with DM have an overall increased risk of neoplasia and risk for specific forms of neoplasia compared to dogs without DM. ANIMALS: Seven hundred dogs with DM and 700 breed, age, and sex‐matched dogs without DM, examined during the same years. METHODS: Retrospective case‐control study. Odds ratios (OR), corresponding 95% confidence intervals (CI), and P‐values were calculated using conditional logistic regression to determine if dogs with DM had increased odds of developing neoplasia compared to dogs without DM. RESULTS: The overall odds of developing neoplasia were not significantly different in dogs with and without DM. However, dogs with DM had significantly higher odds of developing an adrenal mass (OR, 4; 95% CI, 1.1‐14.2; P = .03) compared to dogs without DM. The odds of developing a splenic mass in dogs with DM (OR, 1.2; 95% CI, 0.99‐1.39) were increased compared to dogs without DM, but this difference was not significant (P = .07). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with DM may be at increased risk for adrenal neoplasia. Awareness of this risk can facilitate early diagnosis of this life‐threatening comorbidity. Larger studies are needed to confirm these findings.