Rhinosporidiosis isolated to the distal clavicle: a rare presentation clinicoradiologically mimicking a bone tumor.

Abstract

Rhinosporidiosis is a chronic granulomatous disease caused by Rhinosporidium seeberi, which commonly affects young men and predominantly involves the mucous membranes of the nose, nasopharynx and eyes. Involvement of extranasal sites including bone has been reported, but rarely. We present a case of a 32-year-old farmer, who presented with a non-tender, fixed swelling over his right shoulder. Radiography and CT imaging showed an expansile, lytic, destructive lesion involving the lateral end of the right clavicle with soft tissue extension. The clinicoradiological impression was that of a primary bone tumor. Biopsy and wide excision of the lesion revealed features of rhinosporidiosis. There were no mucocutaneous lesions. Involvement of bone without associated mucocutaneous lesions is exceedingly rare in rhinosporidiosis. Involvement of the clavicle, as seen in the present case, has not been reported in the English language-peer reviewed literature, to the best of our knowledge.