Adjuvant chemotherapy and overall survival in patients with node positive esophageal adenocarcinoma treated with neoadjuvant therapy and esophagectomy: A retrospective analysis using the National Cancer Database.

Abstract

97 Background: Node positive disease (N+) is frequent (~40%) following neoadjuvant therapy (NAT) and esophagectomy, yet limited data exist regarding the efficacy of adjuvant chemotherapy (AC) in this setting. There are no randomized studies addressing this question and single-institution, retrospective studies have reported mixed findings. Methods: A retrospective analysis was conducted using the National Cancer Database. 2,258 N+ patients were identified who had received NAT (83.3% chemoradiation and 17.7% chemotherapy alone) followed by esophagectomy. Patients with either incomplete staging or treatment data were excluded, as were those who died within 90 days following esophagectomy. Multivariate logistic regression was used to test for differences in patient characteristics between those who did (AC+) or did not (AC-) receive AC. Overall survival (OS) after surgery, by AC status, was analyzed using Cox regression in a sample propensity matched on relevant demographic and clinical factors. Results: 433/2258 patients received AC (19.2%). Patients who received AC tended to be younger (OR 0.98 per 1-year increase, P = .03) and had a higher socioeconomic status (SES) (OR 1.47 for high vs. low SES, P = .01). Although there were no significant differences in comorbidity (P = .32), AC+ patients had significantly shorter hospital stays after surgery (OR 0.98 per 1-day increase, P = .03). Pathologic T classification was unrelated to the likelihood of receiving AC (P = .39), however patients with a higher pathologic N stage were more likely receive AC (OR 2.12 for pN3 vs. pN1, P < .001). Those receiving AC had demonstrably longer OS from the time of surgery than those who did not (HR 0.78, P = .004). Median OS for the entire cohort was 22.6 months, whereas the administration of AC was associated with an improvement in median OS of 6.2 months (26.3 vs. 20.1 months). Conclusions: This retrospective analysis indicates that AC is associated with a significant improvement in OS (median 6.2 months) in N+ patients following NAT and esophagectomy. Further studies are needed to clarify the optimal role of AC in this setting.