INS and colorectal cancer: Diabetic patients using insulin had an increased risk of colorectal cancer as compared with those not using it (OR 2.20, 95% CI 1.12–4.33); the OR increased with increasing duration of insulin use and was 8.18 (95% CI 2.06–32.50) for ≥10 years of use (p-value for trend 0.002).