Can endoscopic sinus surgery (i.e. surgery using a long thin tube inserted into the sinuses) help to treat nasal polyposis (soft growths in the nasal passages called polyps) in people with cystic fibrosis (CF)?

Key messages

We are uncertain whether nasal irrigation together with an endoscopic sinus surgery intervention improves symptoms and lung function or reduces the need for antibiotics compared to nasal irrigation alone.

There was one episode of bleeding during surgery that was corrected during the procedure with no further consequences.

What is CF?

CF is a genetic condition that affects the lungs, nose, sinuses and several other organs in the body. The body produces thick sticky mucus that is hard to clear and causes inflammation. Many adults and children with CF have polyps in their nasal passages and sinuses as a result of this sticky mucus and the inflammation. Polyps can lead to more lung infections and a worse quality of life.

How are nasal polyps in CF treated?

Endoscopic sinus surgery aims to open the blocked sinuses to improve breathing and make it easier to clear mucus. It is a procedure with a few side effects (bleeding and damage to the sinuses) linked to it.

Medical treatment includes a number of medicines (both inhaled and swallowed), such as antibiotics, steroids and inhaled medications with humidified oxygen. Saline solutions are also used for nasal blockages. A new group of drugs is available, called cystic fibrosis transmembrane conductance regulator (CFTR) modulators; these drugs are able to correct the basic defect in the CFTR protein, but it is not yet clear how they may affect nasal polyps.

What did we want to find out?

Is endoscopic sinus surgery alone or used together with medical treatment better than medical treatment alone for improving quality of life and lung function without complications in people with CF? We also wanted to know the effects of treatment on bacterial infections, pulmonary exacerbations (flare up of lung disease), need for additional antibiotics and survival.

What did we do?

We looked for studies that compared the different treatments in people who had been diagnosed with CF, polyps and chronic sinus problems. Participants had to have been put into treatment groups in a random order.

What did we find?

Main results

We found a single study which compared nasal irrigation (with saline solution and mometasone (which is a steroid)) in 14 young adults to nasal irrigation with endoscopic sinus surgery in another 14 young adults. The 28 people taking part in the study were aged 19 to 28 years. Those who had surgery as well as using saline irrigation reported a greater improvement in nasal symptoms. They also had a greater reduction in the number of bacteria in their nasal passages, used fewer antibiotics and had fewer pulmonary exacerbations, but there was no difference in their lung function. One person bled more than usual during surgery, but that was successfully dealt with during the procedure with no further consequences. The study did not report on survival.

What are the limitations of the evidence?

Our overall confidence in the evidence was very low because we could not determine how participants were put into the different treatment groups and whether the investigators would know into which group a person would be put. Participants and researchers were not blinded and that could bias some outcomes, including changes in quality of life. Another reason for our low confidence in the evidence is that we found only one study which included a very small number of participants.

How up to date is this evidence?

The evidence is up-to-date to 4 July 2022.

Authors' conclusions: 

Very low-certainty evidence means we are not certain if endoscopic sinus surgery to treat chronic rhinosinusitis with nasal polyposis in cystic fibrosis is effective.

Future research should be multicentric to increase the number of participants and increase statistical power. Adequate randomization and allocation concealment are important to guarantee that the groups are similar. Blinding, however, may not be possible in an ethical trial; even without blinding, results can achieve high-level evidence if the outcomes used are objective parameters. Future research should follow participants of all ages for at least 12 months to evaluate the evolution of nasal polyposis, its recurrence and how symptoms may return. We also consider mortality an important outcome to be assessed. Future clinical research should consider the effects of cystic fibrosis transmembrane conductance regulators, a new group of drugs that may affect the development of nasal polyps.

Read the full abstract...

Cystic fibrosis (CF) is a life-shortening, autosomal recessive disease that leads to abnormal electrolyte concentration in exocrine secretions. Secretion stasis in paranasal sinuses determines chronic rhinosinusitis (CRS) and nasal polyposis. Endoscopic sinus surgery is used to open the sinuses and allow medical treatment to work properly.


To determine the effects of sinus surgery alone or in combination with medical treatment (non-surgical) compared to medical treatment (non-surgical) alone on both nasal and pulmonary function in people with CF diagnosed with CRS with nasal polyposis. Further, to evaluate the impact of sinus surgery (with or without medical treatment) on hospitalization rates, use of antibiotics and pulmonary exacerbation rates.

Search strategy: 

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and hand searching of journals and conference abstract books. Date of last search: 4 July 2022.

We also searched other databases (Pubmed, Embase, World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), Virtual Health Library and Date of last search: 18 September 2022.

Selection criteria: 

Randomized controlled trials (RCTs) comparing groups who underwent endoscopic sinus surgery and groups with medical treatment alone.

Data collection and analysis: 

The review authors independently selected studies, extracted data, assessed the risk of bias and evaluated the certainty of the evidence using GRADE. They contacted the authors of the included study for additional information.

Main results: 

We identified 66 publications relating to 50 studies from electronic searches. Only one study fulfilled the inclusion criteria, and only limited information was available. In this study, 28 participants aged 19 to 28 years were randomized in equal numbers to either nasal irrigation alone or nasal irrigation with surgery (endoscopic polypectomy with extended sinusotomy).

The certainty of the evidence was very low according to the GRADE approach. We are uncertain whether, compared to medical treatment alone, the addition of surgical intervention improves nasal symptoms, or reduces bacterial colonization, the use of antibiotics and pulmonary exacerbations. We are also uncertain whether the addition of surgery to medical treatment leads to changes in pulmonary function. There was one episode of bleeding during surgery that was corrected during the procedure with no further consequences. The study did not report on survival.