Prognostic factors for recurrence after endoscopic sinus surgery for chronic rhinosinusitis with nasal polyps.

Objective: In this study, we aimed to clarify the prognostic factors affecting the ethmoid condition during a long-term follow-up after endoscopic sinus surgery in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).

Methods: Thirty-six patients with CRSwNP underwent surgery from December 2008 to February 2012. All surgeries were performed by one surgeon, and all patients were followed up for at least 2 years postoperatively. We investigated the association of postoperative endoscopic findings with clinical parameters, mucosal eosinophil count and mRNA expression of CCL11, IL-5, and IFN-gamma in nasal polyps.

Results: Seventeen patients (47.2%) had severe mucosal edema, and the patency of each sinus was not confirmed during the >2-year follow-up. The mucosal eosinophil count and two eosinophil-associated factors, namely the CCL11 and IL-5 mRNA levels, were higher in the severe mucosal edema group than in the control group. The severe mucosal edema group was divided into two subgroups: the steroid-responsive and -resistant groups. Five patients (13.9%) had frank polyp formation because the oral steroids were less effective. The mucosal eosinophil count was significantly different among the four groups, including the control group (p=0.001); however, the CCL11, IL-5, and IFN-gamma mRNA levels were not significantly different. Although the IL-5 mRNA level was not significantly different among the four groups, it tended to increase when the sinus condition worsened. In the severe mucosal edema group, a higher IL-5 mRNA level was associated with earlier severe mucosal edema in the ethmoid cavity.

Conclusion: The IL-5 mRNA level is associated with the time of severe edema formation in the ethmoid cavity. This finding permits early intervention on the postoperative course and would prevent polyp recurrence.