These are mainly allergic in nature. You have to take proper treatment of that. With steroid treatment, the polyps can regress in size and give you symptomatic relief.

Surgery

Surgeries for sinonasal polyposis are only to temporarily relieve the physical nasal obstruction. This is necessary in the short term. In the long term however, you need to meet an Allergist and undergo skin-,prick tests to identify the offending allergens that are causing this allergic inflammation in your sinuses and undergo Sublingual Immunotherapy (Slit therapy) to ultimately desensitise your immune system to resolve this issue permanently.