Botryoid rhabdomyosarcoma of the nose: pitfalls of pathology.

A 2-year-old Swiss boy was referred to our hospital because of an obstructive sleep apnea syndrome with suspected recurrent choanal polyp. During surgery, a polypoid soft mass was found in the right nose and extirpated. The histology of the resected polypoid tumor seemed compatible with a polyp; however, immunohistochemistry revealed a botryoid rhabdomyosarcoma. Rhabdomyosarcomas are rare. The most important differential diagnoses for rhabdomyosarcoma are discussed and methods available for differentiating are included.