Lymphoid polyps of the palatine tonsil.

Tonsillar lymphoid polyps are uncommon lesions that have rarely been studied. The authors describe the clinical, histopathologic, and immunohistochemical features of 6 tonsillar polyps in which lymphoid tissue represented more than 80% of the lesion. Presenting symptoms were tonsillar mass and/or dysphagia. No predisposing factor was detected. Microscopically, all polyps contained follicles with germinal centers, crypts lined by lymphoepithelium, and a small amount of fibrous tissue in the center of the lesion. B cells (CD20+), T cells (CD45RO+), plasma cells (kappa+ and lambda+) and vessels (lymphatic, D2-40+; blood, CD34+) presented distribution and architectural patterns as expected for lymphoid tissue of a palatine tonsil. Tonsillar lymphoid polyps are possibly hamartomas characterized by overgrowth of lymphoid elements, which maintain an architectural pattern and cellular composition similar to those of the palatine tonsil.