Prognostic factors for post-operative outcomes in chronic rhinosinusitis with nasal polyps: a systematic review

Chronic rhinosinusitis with nasal polyps (CRSwNP) has a high recurrence rate after surgery despite the availability of medical treatments. Multiple clinical and biological factors have been associated with poor post-operative outcomes in patients with CRSwNP. However, these factors and their prognostic values have not yet been extensively summarized.This systematic review included 49 cohort studies exploring the prognostic factors for post-operative outcomes in CRSwNP. A total of 7802 subjects and 174 factors were included. All investigated factors were classified into three categories according to their predictive value and evidence quality, of which 26 factors were considered plausible for post-operative outcome prediction. Previous nasal surgery, ethmoid-to-maxillary (E/M) ratio, fractional exhaled nitric oxide, tissue eosinophil count or percentage, tissue neutrophil count, tissue IL-5, tissue eosinophil cationic protein, and CLC or IgE in nasal secretion provided more reliable information for prognosis in at least two studies.Exploring predictors through noninvasive or minimally invasive methods for specimen collection is recommended for future work. Models combining multiple factors must be established, as no single factor is effective for the whole population.