The Epidemiology of the Most Frequent Cancers in Poland in 2015-2021 and the Impact of the COVID-19 Pandemic on Cancer Incidence

Background: The late diagnosis, despite the improving availability and accessibility of diagnostic procedures during the last decade in Poland and cooperation between specialist cancer centres, remains an unsolved problem. Moreover, the accessibility to healthcare resources and diagnostic procedures has been drastically reduced because of the COVID-19 pandemic in 2019-2020. The study aimed to present the epidemiology of the most frequent cancers diagnosed in Poland as well as the impact of the COVID-19 pandemic on cancers' incidence.

Methods: Depersonalized, epidemiological data was obtained from the National Health Fund of Poland. In this retrospective study, the epidemiological analysis was performed and divided into subregions, according to patients' domicile. For each of the subregions, we have calculated the incidence rate per 100,000 standardized to the European Standard Population 2013. The time points of providing the first healthcare service were considered as the time of cancer diagnosis.

Results: In the 2015-2019 period, before the COVID-19 pandemic occurred, the nationwide incidence of analysed cancers remained stable or slightly decreased (as the lung cancer). Simultaneusly, during the same period the prevalence of the prostate cancer has increased and the large differences between subregions with the least and the highest incidence were observed. Subsequently, the incidences of all analyzed cancers decreased in 2020, compared to the period before the COVID-19 pandemic occurred. Then, in 2021 a disproportionate increase in cancers' incidence rates was noted.

Conclusions: Our results show a significant decrease in the incidence rate of the most frequent cancers diagnosed in Poland in 2020 compared to 2019. Subsequently, in 2021 the increase of the incidence ratios was noted, most likely due to the gradual reduction of epidemic restrictions.