Paraganglioma of the palatine tonsil.

Paragangliomas of the head and neck are rare. We describe the case of an 11-year-old girl who presented with an enlarged right palatine tonsil (grade 4). After a bilateral tonsillectomy, microscopic examination of the right tonsillar tissue revealed well-formed nests of polygonal epithelial cells separated by a collagenous stroma. The tumor cell nuclei were centrally placed and featured finely clumped chromatin and moderate anisonucleosis. Occasional mitotic figures were present. No necrosis was seen. An immunohistochemical staining panel showed no label for keratin, epithelial membrane antigen, HMB-45, or Melan-A; there was a strong label of tumor cells with chromogranin A, synaptophysin, and neuron-specific enolase. The S-100 protein label was strongly positive in the surrounding stromal cells and weakly positive in the polygonal tumor cells. Given the classic histology and the immunohistochemical staining profile, the diagnosis of paraganglioma was made. At 7 months postoperatively, the patient exhibited no evidence of recurrence or metastasis. To the best of our knowledge, no case of a paraganglioma of the palatine tonsil has been previously described in the literature.