Endoscopic sinus surgery in adult patients with chronic rhinosinusitis with nasal polyps (PolypESS): study protocol for a randomised controlled trial

BACKGROUND: Chronic rhinosinusitis with nasal polyps is a chronic disease frequently seen in otorhinolaryngological practice. Along with its chronic disease burden it creates high societal costs. Therapy consists of long-term use of medication and, if insufficient, endoscopic sinus surgery. No consensus exists on the right timing and extent of disease that warrants surgery. Furthermore, there is lack of clinical knowledge about the benefit of surgery over medication only. The current trial evaluates the clinical effectiveness and cost-effectiveness of endoscopic sinus surgery in addition to drug treatment versus medication exclusively in the adult patient group with nasal polyps. METHODS: A prospective, multicentre, superiority, randomised controlled (PolypESS) trial in 238 patients aged 18 years or older selected for primary or revision endoscopic sinus surgery by the otorhinolaryngologist was designed. Patients will be randomised to either endoscopic sinus surgery in addition to medication or medical therapy only. Relevant data will be collected prior to randomisation, at baseline and 3, 6, 12, 18 and 24 months after start of treatment. Complete follow-up will be 24 months. Primary outcome is disease-specific Health-related Quality of Life quantified by the SNOT-22 after 12-month follow-up. Secondary outcomes are generic Health-related Quality of Life, cost-effectiveness, objective signs of disease and adverse effects of treatment. Subgroup analyses will be performed to verify whether treatment effects differ among patient phenotypes. DISCUSSION: The PolypESS trial will investigate tailored care in adult patients with chronic rhinosinusitis with nasal polyps and will result in improved clinical pathways to help to determine in which circumstances to perform surgery. TRIAL REGISTRATION: Dutch Trial Register, NTR4978. Registered on 27 November 2014. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-016-1728-z) contains supplementary material, which is available to authorized users.