The state of oncological care for gastric cancer (C16) in Russia: epidemiology, structure, mortality, and diagnostic opportunities. Part 1 (Clinical-population study)
The study analyzes one-year and year-by-year mortality, the detailed localization and histological structure of gastric cancer (GC) based on the population-based cancer registry of the NorthWestern Federal District of the Russian Federation (PCR NWFD RF) in comparison with official state reporting, as well as the role of modern diagnostic approaches in improving survival rates. A systematic underestimation of one-year mortality in official Form No. 7 (40.0% in Russia and 42.7% in the NWFD RF, 2023) is demonstrated relative to the PCR NWFD RF data, where the verified rate was 54.2% (2020–2022). Over the entire observation period, one-year mortality according to the registry decreased from 62.6% to 54.2%; year-by-year mortality is gradually declining, yet even after 15 years only 7.7–24.3% of patients survive. The detailed localization structure of GC remains relatively stable; an almost twofold reduction in the proportion of unspecified localizations (C16.9 — from 41.2% to 22.3%) was observed. One-year observed survival for C16 reached 45.8%, and for cancer of the gastric body (C16.2) — 53.5%, which exceeds the European average. Despite a stable histological structure, the discipline of morphological verification improved substantially: the proportion of cases without histological confirmation fell from 23.3% (2000–2004) to 9.2% (2020–2022). It has been demonstrated that the modern multi-step diagnostic algorithm (esophagogastroduodenoscopy with NBI, CT, endoscopic ultrasound, laparoscopy) represents a key reserve for further improving one-year survival. An objective assessment of oncological care for GC requires the mandatory use of PCR data extracted no earlier than one year after the end of the reporting period. Calculations of year-by-year mortality, detailed localization and histological structure with assessment of observed survival, which are unique for Russia, are performed only in the NWFD RF. Improving the quality of primary registration and the widespread implementation of modern diagnostic and staging methods form the basis for reducing one-year mortality and increasing survival in patients with gastric cancer.