Nasal polyps

Nasal polyps are a common head and neck lesion. They are typically benign but may be malignant.

Overview

DDx (benign - multiple):

• Autoimmune/idiopathic:
  • Asthma.
  • Allergic rhinitis.
  • Churg-Strauss syndrome (AKA allergic granulomatous angiitis).
    • Features: asthma, eosinophilia, granulomatous inflammation, necrotizing systemic vasculitis, and necrotizing glomerulonephritis.
  • Nonallergic rhinitis with eosinophilia syndrome (NARES).
• Infectious:
  • Fungal infection (with allergic component - AFS = allergic fungal sinusitis).
  • Chronic rhinosinusitis.
• Genetic:
  • Primary ciliary dyskinesia.
  • Cystic fibrosis.
• Associations:
  • Alcohol intolerance ~ 50%.
  • Aspirin intolerance - upto ~ 25%.
• Tumours:
  • Juvenile nasopharyngeal angiofibroma - young males.
  • Nasopharyngeal carcinomas.
  • Sarcomas.
  • Hemangioma.
  • Schneiderian papilloma.
  • Other.

Memory devices:

• GAIT = Genetic, Allergic/idiopathic, Infectious, Tumours.
• Allergic causes As - allergic, asthma, allergic granulomatous angiitis (Churg-Strauss syndrome), nonallergic rhinitis with eosinophilia.

Epidemiology

• More commonly assoc. with nonallergic conditions.

Treatment

• Recurrent polyps: functional endoscopic sinus surgery (FESS).

Inflammatory polyps with neutrophils

General

• Histologic findings are non-specific; DDx includes:
  • Cystic fibrosis.
  • Primary ciliary dyskinesia syndrome.
  • Young syndrome

Microscopic

Features:

• Neutrophil predominant.
• Edema.
• +/-Mucus-impaction (dilated glands with mucus).
  • Suggestive of cystic fibrosis.

Sign out

A. Nasal sinus tissue, right, excision:
- Inflamed edematous sinonasal mucosa with abundant neutrophils.
- Negative for malignancy.

B. Nasal sinus tissue, left, excision:
- Inflamed edematous sinonasal mucosa with abundant neutrophils and fragments of bone.
- Negative for malignancy.

Alternate

A. Contents of Left Ethmoid Sinus, Excision:
     - Mildly inflamed sinonasal mucosa with bone and fibrous tissue.
     - NEGATIVE for malignancy.

B. Contents of Right Ethmoid Sinus, Excision:
     - Mildly inflamed sinonasal mucosa with bone and fibrous tissue.
     - NEGATIVE for malignancy.

Allergic nasal polyp

General

• People with allergies.
  • Same type of polyps seen in those without allergies.

Gross

• Polypoid mass - several millimetres to centimetres in size.
  • Translucent.^{[citation needed]}

Microscopic

Features:

• Normal respiratory epithelium.
• Stroma with:
  • Edema.
  • Eosinophils.
  • +/-Other inflammatory cells (plasma cells, lymphocytes, neutrophils).

DDx:

• Inflammatory nasal polyp with abundant neutrophils.
• Vasculitis.
  • Wegener's granulomatosis.
  • Churg-Strauss syndrome.
• Biphenotypic sinonasal sarcoma - has hypercellular stroma.

Sign out

A. Left Nasal Polyp, Excision:
- Inflamed edematous sinonasal mucosa with abundant eosinophils.
- NEGATIVE for malignancy.

B. Right Nasal Polyp, Excision:
- Inflamed edematous sinonasal mucosa with abundant eosinophils and fragments of bone.
- NEGATIVE for malignancy.

A. Nasal sinus tissue, right, excision:
- Inflamed edematous sinonasal mucosa with abundant eosinophils.
- Negative for malignancy.

B. Nasal sinus tissue, left, excision:
- Inflamed edematous sinonasal mucosa with abundant eosinophils and fragments of bone.
- Negative for malignancy.

Block letters

A. NASAL SINUS TISSUE, RIGHT, EXCISION:
- INFLAMED EDEMATOUS SINONASAL MUCOSA WITH ABUNDANT EOSINOPHILS.
- NEGATIVE FOR MALIGNANCY.

B. NASAL SINUS TISSUE, LEFT, EXCISION:
- INFLAMED EDEMATOUS SINONASAL MUCOSA WITH ABUNDANT EOSINOPHILS AND FRAGMENTS OF BONE.
- NEGATIVE FOR MALIGNANCY.

Schneiderian papilloma

• AKA Schneiderian polyp.
• AKA sinonasal papilloma.

General

• Lumpers vs. splitters debate about whether it is one entity or three.

Subclassification:

• Inverted (Schneiderian) - most common ~60-65%.
• Fungiform (Schneiderian) - less common ~30-35%.
• Oncocytic (Schneiderian) - least common ~5%.

Inverted

• AKA inverted papilloma.
• Usually lateral wall (as the septum as little soft tissue to grow into).
• May transform to carcinoma.

Fungiform

• AKA exophytic papilloma, AKA septal papilloma.
• Low risk of malignant transformation.

Oncocytic

• AKA cylindrical cell papilloma.
• Lateral nasal wall.

Microscopic

Inverted Schneiderian papilloma

Features:

• Well-demarcated epithelial islands in the stroma.
• Squamous +/-surface keratinization or respiratory type epithelium (with cilia).
• +/-Neutrophils.
• +/-Goblet cells.

Notes:

• May mimic invasive SCC.

Images

• Inverted papilloma & verrucous carcinoma (upmc.edu).

• 

  Schneiderian papilloma - very low mag. (WC)

• 

  Schneiderian papilloma - very high mag. (WC)

Fungiform Schneiderian papilloma

Features:

• Exophytic growth pattern - key feature.

Oncocytic Schneiderian papilloma

Features:

• Oncocytes - key feature.
• Exophytic or endophytic growth pattern.

Antrochoanal polyp

• Abbreviated ACP.

General

• Benign.
• Relative common ~5% of nasal polyps.

Epidemiology:

• "Almost always" recur if incompletely excised.
• Originates from maxillary sinus and extends to choana.

Microscopic

Features:

• Respiratory epithelium.
• Relatively pauciglandular - when compared to inflammatory nasal polyps.
• Typically few eosinophils.

DDx:

• Inflammatory nasal polyps.

Sign out

Ethmoid Sinus Contents (Right), Excision:
     - Benign nasal polyp (antrochoanal type) and mildly inflamed sinonasal mucosa.
     - NEGATIVE for malignancy.

See also

• Head and neck pathology.
• Tonsillar lymphangiomatous polyp.