Nomogram prediction for gastric cancer development.

Background: Helicobacter pylori (Hp) and gastric atrophy represent significant risk factors for gastric cancer. Nevertheless, to date no nomogram has been developed to predict gastric cancer based on the specific combination of risk factors, present in individual cases.

Methods: A retrospective-cohort study was conducted using health-screening data collected between 2003 and 2018. Subjects with positive results for anti-Hp antibody were enrolled. Individuals were classified into 4 groups: low-B (low titer without atrophy), high-B (high titer without atrophy), high-C (high titer with atrophy), and low-C (low titer with atrophy). Nomogram prediction models were developed for overall gastric cancers as well as intestinal and diffuse cancers, with each type considered a competing event, by employing both Cox proportional and sub-distribution hazard models. Prediction performance was evaluated using concordance index (c-index) and the area under the curve (AUC) through 10-fold cross-validation.

Results: During a median follow-up period of 5.7 years, 231 new gastric cancer cases developed among the total cohort of 28,311 subjects, including 159 intestinal type, 68 diffuse type, and 4 cases of unknown type. Multivariable analyses indicated that age, body mass index, family history, smoking, and classification into the high-C or low-C group were significant predictors of gastric cancer. The nomograms for intestinal type, diffuse type, and total gastric cancer demonstrated AUC values of 0.82, 0.62, and 0.75, respectively and c-indices of 0.85, 0.54, and 0.76, respectively.

Conclusions: The nomograms for gastric cancer prediction would be useful in identifying high risk individuals, particularly for intestinal type. This would facilitate the implementation of personalized eradication and intensive screening strategies to target those at higher risk for gastric cancer.