Background
Postoperative infection increases cancer recurrence and worsens survival for colorectal cancer, but the relationship after esophagectomy for esophagogastric adenocarcinoma is not well-defined. We aimed to determine whether recurrence and survival after minimally invasive esophagectomy for esophagogastric adenocarcinoma were influenced by postoperative infection using propensity-matched analysis.
Methods
We abstracted data for 810 patients (1997–2010) and defined exposure as at least one in-hospital/30-day infectious complication (n=206; 25%). Using 29 pretreatment/intraoperative variables, patients were propensity score matched (caliper=0.05). Time-to-cancer recurrence and survival (Kaplan-Meier curves, Breslow test), and associated factors (Cox regression with shared frailty) were assessed.
Results
After propensity-matching (n=167 pairs), median bias across propensity score variables was reduced from 12.9% (p<0.001) to 4.4% (p=1.000). Postoperative infection was not associated with rate (n=60 versus 63; McNemar’s p=0.736) or time to recurrence in those who recurred (median 10.7 versus 11.1 months; Wilcoxon signed-rank p-value=0.455), but was associated with shorter overall survival (n=124 versus 102 deaths; median 26 versus 41 months, Breslow p=0.002). After adjusting for age, body mass index, neoadjuvant therapy, sex, comorbidity score, positive resection margins, pathologic stage, R0 resection and recurrence, postoperative infection was associated with a 44% greater hazard for death (HR 1.44; 95% CI 1.10–1.89).
Conclusions
In patients with esophagogastric adenocarcinoma, post-esophagectomy infections were not associated with increased rate or earlier time to recurrence when baseline characteristics associated with infection risk were balanced using propensity-matching. Despite this, overall survival was shorter in patients with infectious complications. After adjusting for other important survival predictors, post-esophagectomy continued to be independently associated with worse survival.