Postoperative outcomes of gastric carcinoma with lymphoid stroma.

Background: Gastric carcinoma with lymphoid stroma (GCLS) is a rare subtype of gastric cancer. There have been several reports demonstrating the favorable prognosis of early GCLS without lymph node metastasis (LNM) compared with gastric adenocarcinomas. However, it remains unknown whether advanced GCLS (AGCLS) with LNM has a similar prognosis and clinicopathological features. This study aimed to assess the clinicopathological features of GCLS of all stages.

Methods: We retrospectively assessed 375 patients who were pathologically diagnosed with gastric cancer and underwent curative surgical resection at Tokyo Medical University, Japan, between September 2013 and October 2019. Of these patients, 357 (95.2%) patients were pathologically diagnosed with gastric adenocarcinomas, and 18 (4.8%) patients were diagnosed with GCLS. The GCLS patients (n = 18) were compared with the gastric adenocarcinoma patients (non-GCLS patients, control) (n = 357) in terms of their clinicopathological features and clinical outcome.

Results: The GCLS patients showed significantly predominant upper gastric locations (P = 0.003), lower number of LNM (P = 0.01), and better overall survival rate than the non-GCLS patients (P = 0.029). The predominant upper gastric locations (P = 0.0002), lower number of LNM (P = 0.003), and better overall survival rate (P = 0.04) were significantly correlated in the AGCLS with LNM patients compared with the advanced non-GCLS with LNM patients. For survival analyses, surgical procedure, tumor location, and numbers of positive LNM were adjusted by 1:1 propensity score matching. After adjustment, the overall survival rate was significantly higher in the AGCLS group than in the advanced non-GCLS group (P = 0.03).

Conclusion: AGCLS has distinct clinicopathological features and clinical behavior that are similar to those of early GCLS. AGCLS with LNM patients showed a significantly lower number of LNM and a better survival rate than advanced non-GCLS with LNM patients. To our knowledge, this study is the first report to describe the clinicopathological features of AGCLS.