Nasal polyps - histopathologic spectrum.

Analysis of 345 polypoidal masses in nose and nasal sinuses with clinical diagnosis of nasal polyp, observed in 10 years, revealed 175 (50.7%) non- neoplastic lesions and 170 (49.3%) neoplasms. Among the non- neoplastic lesions, there were 110 cases (62.8%) of true nasal polyps including 74 cases (67.3%) of allergic polyps and 36 (32.7%) inflammatory ones. The next common non- neoplastic polyp was due to rhinosporidiosis (31.4%). Benign neoplastic lesions consisted mainly of haemangioma (45.7%), angiofibroma (23.2%), fibroma (6.2%), transitional cell papilloma, inverted papilloma, adenoma-3.9% each. Squamous cell carcinoma was the commonest malignant lesion encountered (36.6%) followed by 19.5% of adenoid cystic carcinoma,17.1% of anaplastic carcinoma and 12.2% of transitional cell carcinoma. Adeno carcinoma (4.9%), Mucoepidermoid carcinoma (2.4%), non- Hodgkin lymphoma (4.9%) and embryonal rhabdomyosarcoma (2.4%) were the other malignant lesions.