Minimal length of proximal resection margin in adenocarcinoma of the esophagogastric junction: a systematic review of the literature

The minimal length of proximal margin (PM) in esophagogastric junction cancer has not been established yet and its impact on patient survival remains unclear. Pubmed, Embase and Scopus databases were searched for "adenocarcinoma of the esophagogastric junction", "adenocarcinoma of the gastroesophageal junction" and "cardia cancer", each combined with "proximal margin". English written studies that specified PM length in AEG were included. Survival data in relation to PM were extracted. 13 studies, that were all retrospective case series, with a total number of 2648 patients met inclusion criteria and were analyzed. While 93% of 230 patients with Siewert type I had esophagectomy, 69% of 1270 patients with Siewert type II and 93% of 872 patients with Siewert type III had transhiatal extended gastrectomy. Minimal PM length was treated by five studies and ranged between 2 and 6 cm. While three studies defined minimal PM by the necessary length to obtain R0 resection, two studies found minimal PM length significantly associated with survival. Multivariate analyses revealed in two studies an independent impact of PM on survival, whereas one study did not found any significant relation between PM and survival. One study showed that PM length was significantly associated with survival in T2-4N0-2 tumors, but not in T1 or N3 tumors. In conclusion, available retrospective studies did not allow a conclusion for a minimal length of PM and showed no clear evidence for an impact of PM length on survival. Taking into consideration available data and the shrinkage phenomen, a PM > 2 cm might be necessary to obtain a sufficient PM.