Comparison between signet-ring cell carcinoma and non-signet-ring cell carcinoma of the stomach: clinicopathological parameters, epidemiological data, outcome, and prognosis—a cohort study of 123 patients from a non-endemic country

Background: Signet-ring cell carcinoma of the stomach (SRCC) is a particular gastric cancer entity. Its incidence is increasing. Its diagnosis is pathological; it corresponds to adenocarcinoma with a majority of signet-ring cells component (> 50%). These histological features give it its aggressiveness characteristics. This has repercussions on the prognostic level and implications for the alternatives of therapy, especially since some authors suggest a potential chemoresistance. This survey aimed to identify the epidemiological, pathological, therapeutic, and prognostic characteristics of SRCC as a separate disease entity. Methods: This was a retrospective study of 123 patients admitted for gastric adenocarcinoma to Habib Thameur Hospital in Tunis over 11 years from January 2006 to December 2016. A comparative study was performed between 2 groups: the SRCC group with 62 patients and the non-SRCC (non-signet-ring cell carcinoma of the stomach) with 61 patients. Results: The prevalence of SRCC in our series was 50%. SRCC affected significantly younger patients (55 vs 62 years; p = 0.004). The infiltrative character was more common in SRCC tumors (30.6 vs 14.8%; p = 0.060), whereas the budding character was more often noted in non-SRCC tumors (78.7 vs 58.1%; p = 0.039). There was no significant difference in tumor localization between both groups. Linitis plastica was noted in 14 patients with SRCC against a single patient with non-SRCC (p = 0.001). The tumor size was more important in the non-SRCC group (6.84 vs 6.39 cm; p = 0.551). Peritoneal carcinomatosis was noted in 4.3% of cases in the SRCC group versus 2.2% of cases in the NSRCC group (p = 0.570). Total gastrectomy was more often performed in the SRCC group (87 vs 56%; p = 0.001). Resection was more often curative in the non-SRCC group (84.4 vs 78.3%; p = 0.063). Postoperative chemotherapy was more commonly indicated in the SRCC group (67.4 vs 53.3%; p = 0.339). Tumor recurrence was more common in the non-SRCC group (35.7 vs 32%; p = 0.776). The most common type of recurrence was peritoneal carcinomatosis in the SRCC group (62.5%) and hepatic metastasis in the non-SRCC group (60%; p = 0.096). The overall 5-year survival in the SRCC group was lower than in the non-SRCC group, with no statistically significant difference (47.1 vs 51.5%; p = 0.715). The overall survival was more important for SRCC in early cancer (100 vs 80%; p = 0.408), whereas it was higher for non-SRCC in advanced cancer (48.1 vs 41.9%; p = 0.635). Conclusion: Apart from its epidemiological and pathological features, SRCC seems to have a worse prognosis. Indeed, it is diagnosed at a more advanced stage and has a worse prognosis in advanced cancer than non-SRCC. It is therefore to be considered as a particular entity of gastric adenocarcinoma requiring a specific therapeutic protocol where the place of chemotherapy remains to be more investigated.