Avoiding perioperative dexamethasone may improve the outcome of patients with rectal cancer

Background Perioperative administration of dexamethasone may augment recurrence and mortality after tumor resection possibly by immunosuppression, which, unfortunately, has never been noted. We therefore carried out a retrospective study in rectal cancer to validate the hypothesis. Methods Five hundreds and fifteen patients with stage I to III rectal cancers who underwent a curative resection from June 2007 and June 2011 were enrolled in the current study. Patients who had been given intravenous (IV) dexamethasone (4–10 mg) postoperatively and/or intraoperatively were assigned to dexamethasone group. The outcome of dexamethasone group and non-dexamethasone group were compared. The primary outcome was disease-free survival (DFS) and overall survival (OS). Results dexamethasone group had significant lower three-year DFS (62.3% vs 71.8%, P = 0.026) and OS (74.1% vs 82.9%, P = 0.031) rate in comparison to non-dexamethasone group, the hazard ratios (HRs) of which were 1.59 (95% CI 1.05–2.39, P = 0.028) and 1.77 (95% CI 1.05–3.01, P = 0.034), respectively. Multivariate analysis revealed that administration of systemic dexamethasone were independently associated with DFS [adjusted HR 1.60 (95% CI 1.03–2.49, p = 0.039)], but for OS, dexamethasone didn't remain significant in this model. In the analyses of a subgroup of 428 patients (55/428 in dexamethasone group) without perioperative blood transfusion, dexamethasone had independently impact on both DFS and OS. Conclusion Patients not given dexamethasone had better three-year survival outcomes compared with patients given dexamethasone perioperatively. Our results indicate that rectal cancer patients treated with curative surgery may get survival benefit from avoiding low-dose perioperative dexamethasone.