Effect of Preoperative Tumour Under-Staging on the Long-Term Survival of Patients Undergoing Radical Gastrectomy for Gastric Cancer.

Purpose: This study aimed to evaluate the effect of preoperative tumour staging deviation (PTSD) on the long-term survival of patients undergoing radical gastrectomy for gastric cancer (RGGC).

Materials and Methods: Clinicopathological data of 2 346 patients who underwent RGGC were retrospectively analysed. The preoperative tumour-lymph node-metastasis (TNM) under-staging group (uTNM) comprised patients who had earlier preoperative TNM than postoperative TNM, and the no preoperative under-staging group (nTNM) comprised the remaining patients.

Results: There were 1 031 uTNM (44.0%) and 1 315 nTNM cases (56.0%). Cox prognostic analysis revealed that PTSD independently affected the overall survival (OS) after surgery. The 5-year OS was lower in the uTNM group (41.8%) than in the nTNM group (71.6%). The patients less than 65 years old, with lower ASA score, 2~5 cm tumour located at the lower stomach, and cT1 or cN0 preoperative staging would more likely undergo D1+ LND in uTNM (p < 0.05). Logistic analyses revealed that tumour size >2 cm and BMI ≤22.72 kg/m2 were independent risk factors of preoperative TNM tumour under-staging in patients with cT1N0M0 staging (p < 0.05).

Conclusion: Underestimated tumour staging is not rare, which possibly results in inadequate LND and affects the long-term survival for patients undergoing RGGC. D2 LND should be carefully performed in patients who are predisposed to this underestimation.