Describe nasal polyps with their causes and management.

Nature and Pathology

• Nasal polyps are benign, pedunculated, oedematous masses of prolapsed, inflamed sinonasal mucosa.
• They are not tumours and not a disease in themselves, but the end result of chronic mucosal inflammation — which is why removing them without treating the inflammation guarantees recurrence.
• They arise chiefly from the ethmoid air cells and the middle meatus, prolapsing into the nasal cavity through the osteomeatal complex

Clinical Features and Management

• Symptoms — progressive bilateral nasal obstruction.
• Massive polyposis may cause broadening of the nasal bridge and hypertelorism — the so-called frog-face deformity — and polyps may become visible at the nostril
• The critical clinical discrimination IS bilateral versus unilateral:
• Bilateral polyps are usually inflammatory and benign
• A unilateral nasal mass is not a simple polyp until proved otherwise, and must be imaged and biopsied — the differential being antrochoanal polyp, inverted papilloma, angiofibroma, malignancy, encephalocele and a fungal ball
• The features that should alarm — unilateral disease; bleeding or a friable, fleshy appearance; pain; orbital signs, proptosis or diplopia; cranial nerve involvement or facial numbness; and bone erosion on imaging
• Investigation — nasal endoscopy; CT of the sinuses to assess extent, the osteomeatal complex, the skull base and any bone erosion; MRI where a tumour, encephalocele or intracranial extension is suspected; allergy testing; and sweat chloride in a child
• Histology of everything removed, without exception
• Medical treatment first:
• Topical intranasal corticosteroid, long-term, which is the mainstay and shrinks polyps, improves obstruction and delays recurrence. Drops reach the ethmoids better than sprays and are used with the head-down position in significant polyposis
• A short course of oral corticosteroid ("medical polypectomy").
• High-volume saline irrigation; treatment of allergy and asthma; leukotriene antagonists in aspirin-exacerbated disease; and antibiotics only for acute infective exacerbations
• Biologics — dupilumab, omalizumab and mepolizumab for severe, recurrent type-2 polyposis.
• Surgery — endoscopic polypectomy with FESS, indicated for failure of medical treatment, complete obstruction, complications, and diagnostic uncertainty
• The operation must address the ethmoids, not merely remove the visible polyps — simple polypectomy alone has a very high recurrence rate.
• Medical treatment must continue after surgery, indefinitely; surgery removes polyps but does not treat the inflammation that makes them
• Counsel about recurrence explicitly — it is common, particularly with asthma, aspirin sensitivity and eosinophilic disease, and a patient who was promised a cure will be justifiably dissatisfied
• Polyps in a child mean cystic fibrosis until the sweat test says otherwise; they are rare in childhood
• A unilateral polyp is a tumour until histology says otherwise, and must be imaged and biopsied rather than simply removed
• Polyps are pale, insensitive and do not bleed, which distinguishes them from every dangerous differential
• They are a symptom of inflammation, not a disease, which is why removing them without continuing steroid guarantees recurrence
• Samter triad is polyps, asthma and aspirin sensitivity, and these patients have the most aggressive and recurrent disease
• Aspirin must be avoided absolutely in that group, since a single dose can precipitate severe bronchospasm
• Leukotriene antagonists suit aspirin-exacerbated disease, which follows directly from the shunting of arachidonic acid
• Eosinophils in the usual type and neutrophils in cystic fibrosis.
• Anosmia is the least reversible symptom and frequently the most distressing, and should be discussed honestly
• Steroid drops reach the ethmoids better than sprays, used with the head down, in significant polyposis
• Oral steroid is a medical polypectomy and may restore smell, but cannot be repeated indefinitely
• Biologics have changed the outlook for the worst-affected, shrinking polyps and restoring smell where surgery could not
• Address the ethmoids, not just the visible polyps; simple polypectomy alone recurs at a very high rate
• Continue medical treatment indefinitely after surgery, and say so before operating rather than afterwards
• Send everything removed for histology, without exception, whatever the operative appearance suggested