An evaluation of neural invasion in esophageal cancer.

It is well known that the operative results for esophageal cancer, especially thoracic esophageal cancer, are not favorable. We analyzed the relationship between neural invasion (NI) and histopathologic factors and recurrence types in 104 patients who underwent resection of esophageal cancers with T2 or greater depth of invasion of the esophageal wall. The implications of NI as a prognostic indicator were also examined. Of the 104 patients, 48 (46.2%) were NI-positive (NI(+)) and 56 (53.8%) were NI-negative (NI(-)). The NI(+) patients had a higher ratio of type 3 cancer. Concerning the histopathologic factors, there was a significant relationship between NI and lymph node metastasis (N) and between NI and lymphatic vessel invasion (ly) (P < 0.05). Examining the types of recurrence, namely hematogenous, lymphogenous, and local/stump, as well as pleural or peritoneal dissemination, a relationship was observed between lymphogenous recurrence and N or ly, and between local/stump recurrence and NI. The prognosis of the NI(+) patients was significantly different from that of the NI(-) patients. According to a multivariate analysis, NI and N were significant prognostic factors. These findings demonstrate that NI is an important prognostic factor closely related to local recurrence in patients with esophageal cancer. Thus, when treating advanced esophageal cancer with T2 or greater depth of invasion, NI and lymph node excision should be considered.