Using the digital archive of pathological reports of stomach cancer as internal quality control of coding according to the ICD-O system

Purpose of the study. Demonstrate the possibilities of statistical analysis of the digital archive at pathological department (PD). To conduct internal quality control of the coding of malignant tumors according to the ICD-O-3 system of pathology reports using the example of gastric cancer (GC).Materials and methods. We retrospectively analyzed the digital archive of 368,157 pathology reports of the National Medical Research Centre for Oncology of the Ministry of Health of Russia from 2000 to 2019. For the study, 4,857 pathology reports of patients operated for gastric malignancies (ICD-X codes: C16.0 – C16.9) were selected for the period from 2000 to 2019.Results. The analysis of 368,157 protocols of the digital archive of PD revealed 4,614 malignant epithelial tumors of the stomach: tubular adenocarcinoma – 2,958, signet ring cell carcinoma – 791, undifferentiated cancer – 565, mucinous adenocarcinoma – 210, neuroendocrine neoplasia – 90. A significant increase in the ICD-O codes for "adenocarcinoma NOS" was found in 2018 and 2019. The pathology reports for these 2 years were reviewed by an independent pathologist and changes were made to the ICD-O codes according to the WHO classification digestive system tumors 2019. The adenocarcinoma NOS (8140/3) was replaced by the codes: tubular adenocarcinoma (ICD-O: 8211/3) – 41%, papillary adenocarcinoma (8260/3) – 9% and adenocarcinoma with mixed subtypes (8255/3) – 29%.Conclusion. The study, based on analysis of coding ICD-O stomach MN demonstrated the importance of digital archive at the PD, as a tool for rapid static analysis pathology reports and quality control of coding. The coding system can be the basis for large multicenter studies in oncology. Therefore, it is important to control the quality of coding of the pathology reports and to timely update the codes when new pathological classifications are released.