Background: The phosphaturic mesenchymal tumor of the craniofacial sinuses (mixed connective tissue variant) is an extremely rare, distinctive paraneoplastic syndrome that is frequently associated with oncogenic osteomalacia.
Methods: In this report is presented a case of 22 years old man indicated four years of progressive generalized pain and weakness, eventually becoming wheel-chair bound. His current presentation was for chest pain resulting from atraumatic rib fractures.
Results: Imaging showed osteoporosis and multiple insufficiency fractures. CT and MRI showed an ethmoid mass. He had no symptoms referable to his nose or sinuses.
Conclusions: The ethmoid lesion was completely excised, the patient's laboratory parameters returned to normal levels and the patient's symptoms disappeared.
Keywords: diagnostic imaging; insufficiency fracture; oncogenic osteomalacia; phosphaturic mesenchymal tumor.