Asthma, Eosinophils Linked With Nasal Polyposis Recurrence

The recurrence rate at 10 years for chronic rhinosinusitis with nasal polyps (CRSwNP) is high, but intranasal steroid therapy is the main treatment to prevent relapse, according to findings published in the American Journal of Otolaryngology.

Although the etiology of CRSwNP remains largely unclear, researchers note that there are several predisposing factors for the disease, including asthma, allergy, and aspirin-exacerbated respiratory disease (AERD).

These factors, along with eosinophils, have also been referenced as risk factors for recurrence of the condition. Prior research has indicated that recurrence of CRSwNP is highly variable, affecting 55% to 60% of cases, in which intranasal and systemic corticosteroids serve as the current standard of care and endoscopic sinus surgery (ESS) is performed when patients are unresponsive to such treatment.

“The main limitation of these studies was a short follow-up. In particular, most authors limited evaluations at 1-5 years after surgery. Only 3 studies had a follow-up interval that reached 10-12 years,” wrote the study authors.

Seeking to further evaluate recurrence risk of CRSwNP after a long-term follow-up, they conducted a retrospective study of 61 patients who underwent their first ESS procedure between 1999 and 2017. Analyses included the role of risk factors, recurrence rate and time to first recurrence, median number of recurrences per year and time interval among them, and the role of nasal cytology.

Participants underwent follow-up examination and nasal cytology at the ​​Division of Otorhinolaryngology, Department of Surgical Sciences, University of Turin from 2019 to 2020. The Kaplan-Meier method was used to obtain the recurrence-free survival curves.

Regarding the study cohort, the mean (SD) age at first ESS and at follow-up examination was 47.05 (11.24) and 57.57 (10.92) years, respectively. Nasal cytology examinations at follow-up found eosinophil inflammation in 22 patients (36.1%), neutrophil inflammation in 11 patients (18.0%), and normal cytology in 28 patients (45.9%). Use of nasal steroids was reported in 26.2% of cases, with isotonic saline solution reported by 77.0% of patients.

Overall, 94 recurrences were reported among participants, with 55.3% of cases treated with oral or intramuscular systemic steroids and ESS performed in the remaining 44.7% of patients. Recurrence rates at 5- and 10-year intervals were 30.29% and 66.06%, respectively.

“Median recurrence-free survival was 106 months. Awaiting a sufficiently long time (20 years), Kaplan-Meier estimator showed that all the patients seemed to have polyposis recurrence,” noted researchers.

Although the log-rank test did not show any statistically significant patient characteristics pertaining to recurrence, asthma and AERD were shown to be predictors of multiple recurrences at the histological exam (P < .05).

Furthermore, patients with normal cytology at follow-up evaluation exhibited a lower probability to have first recurrence within 10 years (59% of cases), compared with neutrophil (100% of cases) and eosinophil infiltrate (88% of cases) (P < .05). Intranasal steroids were the main treatment to prevent relapses (P < .05).

“Further studies with large samples and long follow-up are mandatory to investigate the role of nasal cytology in daily practice in order to identify subjects with a higher risk of early recurrence and that need more intensive post-operative treatment to prevent it,” concluded the study authors.

Reference

Riva G, Tavassoli M, Cravero E, et al. Long-term evaluation of nasal polyposis recurrence: A focus on multiple relapses and nasal cytology. Am J Otolaryngol. 2021 Dec 16;43(2):103325. doi:10.1016/j.amjoto.2021.103325