Differences in prognosis of Siewert II and III oesophagogastric junction cancers are determined by the baseline tumour staging but not its anatomical location

Abstract BACKGROUND The anatomical Siewert classification for adenocarcinoma of the oesophagogastric junction (OGJ) was dictated by the potential differences in tumour epidemiology and pathology. However, there are some uncertainties whether the distinction of true carcinoma of the cardia (type II) and subcardial gastric cancer (type III) is of clinical value. METHODS Using a multicentre data set, we studied 243 patients with OGJ adenocarcinomas who underwent gastric resections between 1998 and 2008. Postoperative complications and long-term survival were compared to evaluate the potential differences in clinically relevant outcomes. RESULTS A group of 109 patients with Siewert type II and 134 with Siewert type III OGJ adenocarcinoma was identified. Both groups showed similar baseline characteristics, including clinical symptoms and duration of diagnostic delay. However, the prevalence of node-negative cancers and superficial (T1-T2) lesions was significantly higher among type II tumours, i.e. 42% vs 21% ( P =0.003) and 43% vs 20% ( P =0.045), respectively. Morbidity and mortality rates were 25% and 3.7%, respectively, but types and incidence of postoperative complications were not affected by the anatomical location of the tumour. The overall median survival was significantly longer for Siewert type II tumours (42 vs 16 months; P 70 years, depth of tumour infiltration, lymph node metastases, distant metastases, and radical resection were identified as independent prognostic factors using the Cox proportional hazards model. CONCLUSION The topographic-anatomic sub-classification of OGJ adenocarcinomas does not correspond to relevant differences in clinical parameters of safety and efficacy of surgical treatment.