Larfors G, et al. - Whether chronic Helicobacter pylori infection could be a risk factor for chronic myeloid leukaemia (CML) was investigated in this population-based, retrospective case-control study utilizing Swedish registry data about 980 CML patients and 4,960 age- and sex-matched controls. Researchers examined links between markers of past infection with Helicobacter pylori and CML incidence. They observed a significantly increased risk of CML in relation to prior diagnoses of dyspepsia, gastritis or peptic ulcers, as well as previous proton pump inhibitor medication. Meanwhile, they found neither inflammatory bowel disease nor consumption of non-steroid anti-inflammatory drugs was related to CML, this finding suggests that gastrointestinal ulcer or inflammation per se did not influence the risk. A shared background between gastric conditions and CML was indicated by the observed consistent links, which also reinforce the case that Helicobacter pylori could constitute this common risk factor.