INS and diabetes mellitus: Our data on a large cohort of insulin‐treated patients with diabetes, now followed for an average of 30 years and many for over 40 years, showed different patterns of cancer risk for those diagnosed with diabetes under age 30, almost all with type 1 diabetes18 and who form the focus of this paper, and those diagnosed at ages 30 to 49, who are likely to have been predominantly type 2,20 and whom we include as a comparison from the same cohort.