Two unusual lesions in the nasal cavity of infants--a nasal chondromesenchymal hamartoma and an aneurysmal bone cyst like lesion. More closely related than we think?

Benign reparative lesions in the head and neck region in infants are rare and often difficult to classify on histology. Discussed herein are two rare lesions in infants occurring at identical locations in the nasal cavity with striking histologic similarity but different histologic labels. One was a case of nasal chondromesenchymal hamartoma (NCMH) occurring in a 1-year-old child and the other an aneurysmal bone cyst (ABC) like lesion affecting a 4-month infant. Both these lesions were locally destructive and had nearly similar clinical presentation. Both on immunohistochemistry showed myofibroblastic nature and had similar histology except that the ABC like lesion lacked the cartilage component of the former. In view of great similarity in the two lesions, it was thought that the second lesion might also represent a reparative, non-cartilage-containing counterpart of the former.