Surgically Managed Signet Ring Cell Esophageal Carcinomas in the National Cancer Database

Background. Signet ring cell adenocarcinoma (SRC) is a less common histologic variant of esophageal adenocarcinoma (ACA). The low frequency of SRC limits the ability to make data-driven clinical recommendations for these patients. Methods. The National Cancer Database was queried for adult patients with clinical stage I, II, or III adenocarcinoma of the noncervical esophagus diagnosed between 2004 and 2015 and stratified by SRC versus all other ACA variants. Cox proportional hazard regression models were adjusted for patient, tumor, and treatment characteristics. The role of surgery in SRC was evaluated among patients treated with chemoradiation alone versus chemoradiation with esophagectomy. Results. Of the 681 SRC and 13,543 ACA patients who underwent esophagectomy, no significant differences in age, sex, race, or comorbidities were identified. Patients with SRC were more likely to have high-grade tumors (84% vs 41%, P <. 001) and stage III tumors (47% vs 39%, P < .001) compared with patients with ACA. Complete (R0) resection was less common in SRC (81% vs 90%, P < .001). Adjusted 5-year mortality risk from surgery was higher for SRC patients compared with ACA patients (hazard ratio, 1.242; 95% confidence interval, 1.126-1.369; P < .001). Among SRC tumors, chemoradiation with esophagectomy was associated with superior survival (hazard ratio, 0.429; 95% confidence interval, 0.339-0.546; P < .001) compared with chemoradiation alone. Conclusions. Among surgically managed patients SRC appears to have a worse prognosis than ACA, which may reflect the tendency of SRC tumors to be higher grade and more locally advanced. However SRC histology does not appear to diminish the role of esophagectomy in the management of locoregionally confined esophageal cancer. (C) 2020 by The Society of Thoracic Surgeons