PURPOSE: To describe the imaging and clinical characteristics of @entity3580 osseous @entity3 (COM). MATERIALS AND METHODS: Our study was IRB approved and HIPAA compliant. A retrospective search of our pathology database for pathology-proven COM yielded 15 @entity1 who had undergone MRI, CT, bone scan, and/or FDG-PET/CT. The imaging and clinical features of the COMs were recorded. A control group of age and gender matched @entity3580 @entity1 without osseous @entity3 was evaluated. RESULTS: The COM mean maximal dimension was 6.4        4.0  cm. The majority (60%) of @entity1 had one lesion. Extra-osseous soft tissue component was present in 85% and was larger than intra-osseous component in 76%. On MRI the lesions were heterogeneous but predominantly T2 hyperintense with hypointense septae, and with variable enhancement. On CT the lesions were typically destructive or permeative; calcifications were rare. The extent of the soft tissue component was isodense to muscle on CT and therefore better evaluated on MRI. COM was in a body part contiguous to the site of the @entity5 . Compared to the controls, COM @entity1 were more likely to have local recurrence (P   =   0.0009) and positive resection margins (P   =   0.002). At 1  year, 33% of COM @entity1 were deceased and 13% had progressive @entity3 . CONCLUSION: COM are associated with large extra-osseous soft tissue components, which are better visualized by MRI. They are often located in a body part contiguous to the site of the @entity5 , portend poor prognosis, and are associated with positive resection margins and local recurrence.

Osseous @entity3 of XXXX : imaging and clinical findings.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity3580 :: ('MESH:D002817', 'Disease') :: ['chordoma'] @entity5 :: ('MESH:D009369', 'Disease') :: ['primary tumor'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastasis', 'metastases']
@entity3580 :: (MESH:D002817,Disease) :: ['chordoma']
