Chapter 30. Nasal Polyps

A 35-year-old man complains of unilateral nasal obstruction for the past several months of gradual onset. On examination of the nose, a nasal polyp is found (Figure 30-1).

Nasal polyps are benign lesions arising from the mucosa of the nasal passages including the paranasal sinuses. They are most commonly semitransparent.

See reference 1.

• Prevalence of 1% to 4% of adults; 0.1% of children of all races and classes.
• The male-to-female ratio in adults is approximately 2:1.
• Peak age of onset is 20 to 40 years old; rare in children younger than 10 years old.
• Associated with the following conditions:
  • Nonallergic and allergic rhinitis and rhinosinusitis.
  • Asthma—In 20% to 50% of patients with polyps.
  • Cystic fibrosis.
  • Aspirin intolerance—In 8% to 26% of patients with polyps.
  • Alcohol intolerance—In 50% of patients with polyps.

• The precise cause of nasal polyp formation is unknown.
• Infectious agents causing desquamation of the mucous membrane may play a triggering role.
• Activated epithelial cells appear to be the major source of mediators that induce an influx of inflammatory cells, including eosinophils prominently; these in turn lead to proliferation and activation of fibroblasts.2 Cytokines and growth factors play a role in maintaining the mucosal inflammation associated with polyps.
• Food allergies are strongly associated with nasal polyps.

Clinical Features

• The appearance is usually smooth and rounded (Figure 30-1).
• Moist and translucent (Figure 30-2).
• Variable size.
• Color ranging from nearly none to deep erythema.

Typical Distribution

• The middle meatus is the most common location.

Laboratory and Imaging

• Consider allergy testing.
• In children with multiple polyps, order sweat test to rule out cystic fibrosis.
• CT of the nose and paranasal sinuses may be indicated to evaluate extent of lesion(s) (Figure 30-3).

Biopsy

• Not usually indicated. Histology typically shows pseudostratified ciliary epithelium, edematous stroma, epithelial basement membrane, and proinflammatory cells with eosinophils present in 80% to 90% of cases.

Many relatively rare conditions can cause an intranasal mass including (in adults):

• Papilloma—About 1% of nasal tumors, affecting 1 in 100,000 adults per year. Locally invasive, these tend to recur especially if excision is not complete. Papillomas are of unknown etiology but are associated with chronic sinusitis, air pollution, and viral infections. They are irregular and friable in appearance and bleed easily.3
• Meningoencephalocele—Grayish gelatinous appearance.4
• Nasopharyngeal carcinoma—Firm, often ulcerated.
• Pyogenic granuloma—Relatively common benign vascular neoplasm of skin and mucous membranes (see Chapter 161, Pyogenic Granuloma).5
• Chordoma—Locally invasive neoplasms with gelatinous appearance that arise from notochordal (embryonic) remnants. Occurs in all age groups (mean age: 48 years).6
• Glioblastoma—Rare manifestation of the most common kind of brain tumor in adults.

Conditions that may mimic nasal polyp in children include:

• Rhabdomyosarcoma—Malignant tumor of childhood originating from striated muscle.
• Dermoid tumor—Inclusion cysts of ectodermal epithelial elements, usually manifest before 20 years of age. May grow slowly.
• Hemangioma—Congenital, abnormal proliferation of blood vessels that may occur in any vascularized tissue (see Chapter 109, Childhood Hemangiomas and Vascular Malformations).
• Neuroblastoma—Unusual presentation of relatively common malignancy of childhood.
• Meningoencephalocele—Grayish gelatinous appearance.
• Angiofibroma—Locally invasive neoplasm that appears as a firm grayish mass. Bleeds easily. Occurs in adolescent males ages 14 to 18 years. Undetermined etiology.7
• Pyogenic granuloma (see Chapter 161, Pyogenic Granuloma).5

Medications

• Medical treatment consists of intranasal corticosteroids.8 SOR A
• An initial short course (2 to 4 weeks) of oral steroids may be considered in severe cases.9,10 SOR A
• Steroid treatment reduces polyp size, but does not generally resolve them. Corticosteroid treatment is also useful preoperatively to reduce polyp size.
• Oral doxycycline 100 mg daily for 20 days was shown to decrease polyp size, providing benefit for 12 weeks in one randomized controlled trial.11 SOR B
• Topical nasal decongestants may provide some symptom relief, but do not reduce polyp size.12 SOR B
• Montelukast reduces symptoms when used as an adjunct to oral and inhaled steroid therapy in patients with bilateral nasal polyposis.13 SOR B

Procedures

• Surgical excision is often required to relieve symptoms.
• Consider immunotherapy for patients with allergies.

Lesions are benign and tend to recur.

• Periodic reevaluation is recommended because recurrence rates are high.14

• Patients should be informed about the benign nature of nasal polyps and their tendency to recur.

Patient Resources

• http://www.mayoclinic.com/health/nasal-polyps/DS00498.
• http://www.nlm.nih.gov/medlineplus/ency/article/001641.htm.

Provider Resources

• http://emedicine.medscape.com/article/994274.
• http://emedicine.medscape.com/article/861353.