title: 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 < 0.001). However, only patients' age >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.
  
  
  CONCLUSIONS
  The topographic-anatomic sub-classification of OGJ adenocarcinomas does not correspond to relevant differences in clinical parameters of safety and efficacy of surgical treatment.
authors.affiliation: First Department of Surgery, Jagiellonian University Medical College, Krakow, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Kulig
authors.affiliation: First Department of Surgery, Jagiellonian University Medical College, Krakow, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Sierzega
authors.affiliation: First Department of Surgery, Jagiellonian University Medical College, Krakow, Poland.
authors.forename: R
authors.initials: R
authors.lastname: Pach
authors.affiliation: First Department of Surgery, Jagiellonian University Medical College, Krakow, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Kolodziejczyk
authors.affiliation: First Department of Surgery, Jagiellonian University Medical College, Krakow, Poland. Electronic address: janmarian.kulig@uj.edu.pl.
authors.forename: J
authors.initials: J
authors.lastname: Kulig
mesh_terms: D000230:Adenocarcinoma / Q000145:classification* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D000368:Aged; D002299:Cardia / Q000473:pathology* / Q000601:surgery; D004943:Esophagogastric Junction / Q000473:pathology* / Q000601:surgery; D005260:Female; D005743:Gastrectomy; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011183:Postoperative Complications / Q000453:epidemiology*; D011379:Prognosis; D016016:Proportional Hazards Models; D013274:Stomach Neoplasms / Q000145:classification* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D015996:Survival Rate
keywords: Adenocarcinoma of the oesophagogastric junction; Gastric cancer; Prognosis; Siewert classification