Characteristics of regional epidemiological indicators of chronic myeloproliferative neoplasms

Background. Information on the epidemiological picture of chronic myeloid leukemia (CML) and, especially, Ph– chronic myeloproliferative neoplasm (MPN) in Russia is very scarce, each regional population study is important for obtaining information on the diseases in general.Aim. To analyze the regional epidemiological parameters of the most common MPN over a long period of time (2012–2023).Materials and methods. Clinical and epidemiological, population, retrospective-prospective, observational study of CML and classical Ph– MPN (polycythemia vera, essential thrombocythemia, primary myelofibrosis) was conducted at the Moscow City Hematology Center, Botkin Hospital. The observation period was from January 1, 2012 to December 31, 2023. The research database included data from the medical records of regional patients (Moscow).Results. At the time of analysis, the database contained 2191 patients with CML and 5831 with Ph– MPN observed since 2000. In both cohorts, women prevailed with a ratio of 1:1.1 for CML and 1:1.6 for Ph– MPN. The median age of patients in the overall cohort since 2000 at diagnosis of CML was 55 years (men – 52, women – 57), and of Ph– MPN – 64 years (men – 62, women – 64). During the study period, an increase in the median age and in the proportion of diagnosed CML patients aged 65 years and older were noted, the same was not observed in Ph– MPN. However, an increase in the median age and the proportion of elderly patients was revealed in both general cohorts of CML and Ph– MPN. The registered prevalence of CML and Ph– MPN over a 12-year period increased by 90 % (from 6.0 to 11.4 cases per 100,000 population) and 93 % (from 15.28 to 29.46 cases per 100,000 population), respectively. The high reliability of linear trends indicates a uniform increase in the prevalence of CML and Ph– MPN. The registered annual incidence rate of CML increased over 12 years from 0.74 to 1.13 cases per 100,000 population, and Ph– MPN – from 2.05 to 2.84. An increasing tendency in registered annual mortality from 0.23 to 0.36 per 100,000 population for CML, from 0.87 to 1.04 per 100,000 population for Ph– MPN was observed. Its maximum rates in both cohorts matched with the COVID-19 pandemia period; for Ph– MPN the increase was more pronounced. All over the investigated period, the registered annual morbidity rate always exceeded the registered annual mortality rate. In general, the pandemic did not have a significant impact on the registered epidemiological parameters of both cohorts. In the total CML group, 2-, 5-, 10-year overall survival (OS) was 91, 82, 68 %, in Ph– MPN – 93, 83, 63 %, respectively; the median OS was not achieved in both cohorts. The 5- and 10-year OS for Ph– MPN differed between male and female cohorts: 86 and 67 % versus 79 and 58 %, respectively (p <0.05). In younger (younger than 65 years) patients, 5- and 10-year OS were higher (p <0.001) than in patients aged 65 years and older: 89 and 80 % versus 63 and 35 % in CML, 92 and 80 % versus 73 and 44 % in Ph– MPN, respectively. The median OS in CML and Ph– MPN was not achieved in patients younger than 65 years, and among older patients it was 90 months in CML and 105 months in Ph– MPN.Conclusion. An assessment of CML and Ph– MPN epidemiological indicators dynamics over a 12-year period made it possible to draw a number of conclusions about the population characteristics of each studied cohorts and to identify similar trends and differences in the changes occuring.