Use of nucleotyping and tumor stroma ratio to predict prognosis in patients with resected intestinal-type gastric cancer.

Abstract

483 Background: Heterogeneity exists in recurrence and survival among patients with intestinal-type gastric cancer (IGC). Nucleotyping is the alterations in chromatin organization. We sought to identify the prognostic utility of nucleotyping, tumor stroma ratio (TSR) and DNA ploidy in these patients. Methods: Radical resection of gastric carcinoma (> 15 LNs removed) was performed in 283 patients (stage I, n=73; stage II, n=102; stage III, n=108) at our university hospital between 2010 and 2018. Automated image cytometry tools were used to quantitatively measure nucleotyping, TSR and DNA ploidy. Cutpoints of nucleotyping and TSR were 0.044 and 50%, respectively. Associations of these features with clinicopathological characteristics, time-to-recurrence (TTR) and cancer specific survival (CSS) were analyzed by univariate and multivariate analysis. Results: Among 283 patients, chromatin heterogeneity, high TSR and non-diploid were significantly associated with larger tumor size, higher T and N stage, and poorer TTR and CSS at 5 years. In a Cox multivariable analysis, nucleotyping and TSR were independently associated with TTR and CSS (P＜0.05) (Table). The top three contributors to TTR were N stage (33.9%), nucleotying (29.7%) and TSR (25.5%). The top three contributors to CSS were N stage (35.6%), nucleotying (29.7%) and TSR (18.0%). As a combined variable, the percent relative contribution of nucleotyping and TSR ranked first for TTR and CSS (56.0%, 50.0%), ahead of N stage (33.4%, 34.6%) and TILs (8.4%, 10.6%). Conclusions: Nucleotyping and TSR were each significantly and independently associated with TTR and CSS, and their combined variable was more strongly prognostic than either alone. Cox multivariable analysis of TTR and CSS. Features TTR HR (95%CI) TTR P value CSS HR (95%CI) CSS P value Tumor size (>3cm vs ≤3cm) 1.10 (0.48-2.54) 0.83 0.77 (0.35-1.70) 0.56 T stage (T3-T4 vs T1-T2) 1.07 (0.46-2.49) 0.87 1.41 (0.53-3.76) 0.49 N stage (N2N3 vs N0N1) 2.84 (1.39-5.78) <0.01 7.69 (3.37-17.55) <0.01 Adjuvant Therapy (with vs without) 1.32 (0.72-2.40) 0.37 0.85 (0.48-1.52) 0.59 TB (high vs low) 1.29 (0.62-2.69) 0.50 1.61 (0.85-3.07) 0.15 TILs（low vs high） 1.73 (0.96-3.13) 0.07 1.90 (1.06-3.40) 0.03 Nucleotyping (Chromatin heterogeneous vs Chromatin homogeneous) 2.19 (1.21-3.99) 0.01 3.44 (1.96-6.03) <0.01 TSR (high vs low) 2.12 (1.16-3.82) 0.01 2.51 (1.43-4.41) <0.01 DNA ploidy (Non-diploid vs Diploid) 1.20 (0.55-2.63) 0.65 0.98 (0.44-2.15) 0.95 1 TTR, time-to-recurrence; 2 CSS, cancer specific survival.