The association between histological subtypes and lymph node metastasis and prognosis in early esophageal cancer: a population-based study

Background There is still a lack of high-level clinical evidence and uniform conclusions on whether there are differences in lymph node metastasis (LNM) and prognosis between early esophageal adenocarcinoma (EAC) and squamous cell carcinoma (ESCC). Methods Patients with surgically resected, histologically diagnosed, pT1 EAC or ESCC in the Surveillance, Epidemiology and End Results registries database from 2004 to 2015 were included. Multivariable logistic regression, Cox regression, multivariate competing risk model, and propensity score matching were used to analyze association the histology and LNM or prognosis. Results A total of 570 early esophageal cancer patients were included. The LNM rates were 13.8% and 15.1% for EAC and ESCC ( P = 0.757), respectively. Multivariate logistic regression analysis showed no significant association between histological type and LNM (odds ratio [OR], 1.209; 95% CI, 0.538–2.715; P = 0.646). Moreover, the prognosis of early EAC and ESCC was shown to be comparable in both multivariate Cox regression (hazard ratio [HR], 1.483; 95% CI, 0.699–3.150; P = 0.305) and the multivariate competing risk model (subdistribution HR, 1.451; 95% CI, 0.628–3.354; P = 0.383). After propensity score matching, there were no significant differences between early EAC and ESCC in terms of LNM (10.6% vs.18.2%, P = 0.215), 5-year CSS (89.8% [95% CI, 81.0%–98.6%] vs. 79.1% [95% CI, 67.9%–90.3%], P = 0.102) and 5-year cumulative incidence of CSS (10.2% [95% CI, 1.4%–19.0%] vs. 79.1% [95% CI, 9.7%–32.1%], P = 0.124). Conclusion The risk of LNM and prognosis of early ESCC and EAC are comparable, so the treatment choice for early esophageal cancer does not depend on the histologic type.