Signet ring cell adenocarcinomas: different clinical-pathological characteristics of oesophageal and gastric locations

International audienceAIMS: The incidence of oesogastric (OG) signet ring cell adenocarcinoma (SRC) is increasing in Western countries. The differential characteristics between oesophageal and gastric SRC tumours are unknown. We aimed to investigate the role of tumour location on prognosis in OG SRC.METHODS: Among 924 OG SRC resected in 21 centres from 1997 to 2010, consecutive patients who had oesophageal tumours (group OESO, n = 136) were matched to randomly selected patients who had gastric tumours (group GASTRIC, n = 363). Matching variables were gender, age, American Society of Anaesthesiologists score, malnutrition, pretherapeutic clinical TNM stage and neoadjuvant treatment. Patients and tumour characteristics were compared between groups and prognostic factors were identified.RESULTS: The two groups were well matched. Tumours in group GASTRIC were more advanced at surgical exploration, with higher rates of linitis plastica (P < 0.001), peritoneal carcinomatosis (P = 0.001), and advanced pTNM stages (P = 0.034). Radicality of resection and recurrence rates were similar (P > 0.480). Recurrences were more frequently distant (P < 0.001) and peritoneal (P < 0.001) in group GASTRIC. After adjustment on confounding variables, gastric location (P = 0.034) was independently associated with a better prognosis than oesophageal location.CONCLUSION: Gastric and oesophageal SRC tumours are distinct diseases. Despite similar pretherapeutic factors, gastric tumours were more advanced with a greater propensity for the peritoneal surface at the diagnosis and recurrence and associated with a better prognosis.