Nodes or no nodes? The lymph node metastasis risk of T1 esophageal cancer revisited.

Endoscopic treatment of early Barrett's neoplasia has gained more and more acceptance over the past 10 years. It is well known that the risk for lymph node and distant metastasis is absent in high-grade dysplasia (HGD) and very low in mucosal Barrett's cancer (T1a) (1,2). However, when the cancer is invading into the sub-mucosal layer (T1b), the risk for lymphatic spread rises substantially (1,2). Therefore, recent guidelines recommend endoscopic treatment for HGD and mucosal adenocarcinoma and esopha-geal resection for submucosal cancer (3). There seems to be a subgroup of patients with submucosal invasion having a very low risk for lymph node metastasis—well and moderately differentiated adenocarcinoma infiltrating only the upper third of the sub-mucosal layer (≤500 μm) without lymphatic or vascular invasion (4). In these cases, endoscopic resection could be an alternative to surgery (3,4). In squamous cell cancer of the esophagus, the risk for lymphatic spread is known to be higher. When the cancer invades the deep mucosal layer (T1m3) the risk rises markedly, up to greater than 10% (5). In the current issue of JNCI, Merkow et al. publish a large retrospective analysis of data from the National Cancer Database, in which they identify 5390 patients with T1 esophageal cancer treated in 824 hospitals in the US between 2004 and 2010 (6). Surgical resection was performed in 73.5% and endoscopic treatment in 26.5%. The vast majority of the tumors were adenocarci-nomas (89%). Interestingly, the authors find that 5% of patients who received esophagectomy for T1a esophageal cancer had at least one positive lymph node. The rate decreased to 0.5% for low-grade lesions smaller than 2 cm in diameter. There was no difference between adenocarcinoma and squamous cell carci-noma. These results are very surprising, because they are contradictory to most recent publications; Hölscher et al. reported a 0% lymph node metastasis rate (0 of 124 patients) for T1a esophageal cancers. In the same issue, Griffin et al. reported a lymph node metastasis rate of 0% (0 of 54 patients) for mucosal esophageal cancers (1,2). In accordance with those findings, our group recently published a large series of 1000 patients with T1a Barrett's adenocar-cinoma treated by endoscopic resection (ER) (7). The long-term outcome was excellent, with a complete remission rate of neopla-sia of 93.8% after almost 5 years of follow-up. More than half of the tumors were larger than 2 cm, and 54 patients even revealed a poorly differentiated adenocarcinoma. …