Population-based assessment of chronic myeloid leukemia in Sweden: striking increase in survival and prevalence

The clinical outcome for patients with chronic myeloid leukemia (CML) has improved dramatically following the introduction of tyrosine kinase inhibitors. An improved survival, combined with a constant incidence, is expected to increase the prevalence of CML. However, data on the prevalence of CML remain scarce. We examined the overall and relative (age and gender matched) survival and assessed the past, present, and projected future prevalence of CML in Sweden. Data on all patients diagnosed with CML between 1970 and 2012 were retrieved from the Swedish Cancer Register and the Swedish Cause of Death Register. The 5-year overall survival increased from 0.18 to 0.82, during the observed time period. Between 2006 and 2012, the 5-year relative survival was close to normal for 40-year-old, but considerably lower for 80-year-old CML patients. The observed prevalence tripled from 1985 to 2012, from 3.9 to 11.9 per 100 000 inhabitants. Assuming no further improvements in relative survival, the prevalence is projected to further increase by 2060 to 22.0 per 100 000 inhabitants (2587 persons in Sweden). The projected dramatic increase in CML prevalence has major medical and health economic implications and needs to be considered in planning how to organize future care of CML patients.