Very Early Recurrence After Curative-Intent Surgery for Gastric Adenocarcinoma.

BACKGROUND: Recurrence after curative-intent surgery can occur in more than 50% of gastric cancer (GC) patients. We sought to identify predictors of very early recurrence (VER) among GC patients who underwent curative-intent surgery. METHODS: A multi-institutional database of GC patients undergoing curative-intent surgery between 2000 and 2020 at 8 major institutions was queried. VER was defined as local or distant tumor recurrence within 6 months from surgery. Univariable Cox proportional hazard models were used to evaluate the predictive value of clinical-pathological features on VER. A regularized Cox regression model was employed to build a predictive model of VER and recurrence within 12 months. The discriminant ability of the Cox regularized models was evaluated by reporting a ROC curve together with the calibration plot, considering 200 runs. RESULTS: Among 1133 patients, 65 (16.0%) patients experienced a VER. Preoperative symptoms (HR 1.198), comorbidities (HR 1.289), tumor grade (HR 1.043), LNR (HR 4.339) and T stage (HR 1.639) were associated with an increased likelihood of VER. Model performance was very good at predicting VER at 6 months (AUC of 0.722) and 12 months (AUC 0.733). Two nomograms to predict 6-month and 12-month VER were built based on the predictive model. A higher nomogram score was associated with worse prognosis. There was good prediction between observed and estimated VER with minimal evidence of overfitting and good performance on internal bootstrapping validation. CONCLUSION: One in 6 patients experienced VER following curative-intent surgery for GC. Nomograms to predict risk of VER performed well on internal validation, and stratified patients into distinct prognostic groups relative to 6- and 12-months recurrence.