Survival among cancers screened at the first stage of Dispanserization of certain groups of the adult population: a population-based epidemiological analysis

Abstract

Objective: to evaluate trends of survival in nine index malignant neoplasms (iMNs), which are screened at the first stage of the Dispanserization of certain groups of the adult population (DCGAP), on data of the Arkhangelsk regional cancer registry over a period 2006-2019.
 Materials and methods. We compared two seven-year periods 2006-2012 and 2013-2019, before and after the introduction of the DCGAP. The 1- and 5-year cancer-specific survival (CSS) rate was calculated using the life table and Kaplan-Meier methods with an assessment of the differences by log-rank. Cox regression analysis with sequential input was used to identify possible causes of differences in survival between periods and independent prognostic factors.
 Results. 37197 cases were selected for analysis. 5-year CSS estimates in 2013-2019 compared with the previous seven-year period significantly increased for all nine iMNs, by from 2.5% [2006-2012, 12.5% ​​(95% confidence interval (CI) 11.4-13.6%) vs 2013-2019, 15.0 (95% CI 13.7-16.5%)] in lung cancer up to 12.6% [2006-2012, 31.0% (95% CI 28.6-33.4%) vs 2013-2019, 43.6 (95% CI 40.8-46.2%)]. Correction for the stage (possible effect of screening) in the Cox model has led to a decrease in the hazard ratio (HR) of death from cancer of the colon, rectum, breast, kidney by 38-64%, no change for other iMNs; while for cervical cancer, it has increased. Adjustment for the variable "treatment method" led to a 34-100% decrease in the HR in the Cox model for all iMNs, except for prostate cancer.
 Conclusion. The increase in survival estimates for nine iMNs in 2013-2019 can be explained to a large extent by improved access to cancer-directed treatment and its quality; the contribution of DCGAP is possible in renal, breast and colorectal cancer.
 Key words: malignant neoplasms, screening, dispensarization of certain groups of the adult population, survival