Age-Related Features of the Prevalence, Early Diagnosis and Survival of Breast Cancer Patients (Clinical and Population-Based Study)

Abstract

Introduction. Breast cancer (BC) is the leading pathology in the incidence of malignant neoplasms (MN) in women aged 30-70 years. Modern screening methods of early diagnosis make it possible to detect MN at an early stage. The modern information system of population-based cancer registries established in the country makes it possible to obtain objective information on the state of the service. An important step in developing the reliability of the data obtained was the organization of a cancer registry in the Northwestern Federal District, which covers about 14 million people in Russia, which is more than the population of Belarus, Latvia and Estonia combined. The accumulated database amounts to more than 1.5 million observations and, most importantly, is used to calculate the observed and relative survival rates of patients.

Aim. To analyze the current state of oncological care in Russia and the Northwestern Federal District of the Russian Federation (NWFD of RF) in terms of the prevalence of breast cancer, early diagnosis and survival of patients, taking into account age characteristics, separately for the female and male population.

Materials and Methods. The study material is statistical data from the International Agency for Research on Cancer (IARC) — Volume XII of the monograph ‘Cancer Incidence in Five Continents’, reference books from the P. Herzen Moscow Oncology Research Institute and the N.N. Petrov National Medical Centre of Oncology, databases of population cancer registries (DB PCR) of St. Petersburg and the NWFD of RF. Data were processed using MS Excel 2013-2016 and STATISTICA 6.1 licensed software. The modified Eurocare program was used to calculate survival rates, as well as mathematical, bibliographic and statistical methods.

Results. The results of the study indicate that breast cancer in Russia and NWFD of RF has average incidence rates ranging from 50-60 ‱₀ among female population and 0.4-1.0 ‱₀ among male population. Between 2000 and 2021, the standardized incidence of female BC increased from 38.2 to 50.42 ‱₀. The coronavirus pandemic has limited the availability of specialized cancer care for nearly 9,000 patients. The country is actively developing new methods of early diagnosis, including digital mammography, aimed at timely detection of non-invasive and early invasive BC. The mortality rate in women from BC for 2021 decreased by 27.73 %, and in men by 17.65 %. The quality of primary patient registration has improved significantly. The highest one-year survival rates for women with BC were recorded in people aged 20-69 years (90 %), and for long-lived people the rate was around 35 %.

Conclusion. This study is the first to examine in detail the nature of age-specific changes in incidence, mortality, record quality of newly registered BC patients and age-specific survival rates, including long-lived people.