Prognostic effect of categorized tumor deposits in gastric cancer: A single-center retrospective study

Tumor deposits are defined as all types of isolated cancer lesions without lymphocyte aggregates considered part of the lymph node. Tumor deposits have been reported as a negative prognostic factor. However, the survival significance of categorized tumor deposits is uncertain, particularly in gastric cancer. This study aimed to investigate the prognostic difference among categorized tumor deposits.

Patients who underwent gastrectomy for gastric cancer were enrolled. All tumor deposits were categorized into irregular nodule, irregular nodule star, smooth nodule, and vascular/neural invasion. There are some cases with more than 2 categorized tumor deposits. These cases were categorized as tumor deposit complex in the following analysis. We performed survival analysis between the patients with and without tumor deposits, and compared the survival among each categorized tumor deposit.

Of 868 patients, there were 96 (11.1%) and 772 (88.9%) patients with and without tumor deposits. Vascular/neural invasion, smooth nodule, irregular nodule, irregular nodule star, and the tumor deposits complex was observed in 6 (6.3%), 15 (15.6%), 43 (44.8%), 1 (1.0%), and 31 (32.3%) patients. Patients with tumor deposits displayed poorer survival than those without; the 3-year overall survival: tumor deposits negative = 87.0%, tumor deposits positive = 53.2% (P < .001). Survival analysis revealed tumor deposits can be a prognostic risk factor (hazard ratio: 1.9854, 95% confidence interval: 1.393-2.830, P < .01). Irregular nodule and the tumor deposits complex demonstrated the worst prognosis (irregular nodule 3-year overall survival: 51.2%, tumor deposits complex 3-year overall survival: 41.9%, P = .001), whereas smooth nodule demonstrated better prognosis (smooth nodule 3-year overall survival: 80%).

Tumor deposits exerted a negative survival effect in gastric cancer. Irregular nodule and the tumor deposits complex displayed a strong prognostic effect.