Claims‐based definitions for cancers have been developed and validated in the USA and EU for the identification of incident cases of breast, lung, gastric, colorectal, and hematologic cancers in hospital or commercial administrative databases3, 4, 5, 6 and, in the USA, for determining the incidence of cancer among patients with inflammatory diseases receiving tumor necrosis factor inhibitors.7, 8. Here, TNF is linked to cancer.