Intraosseous lipoma of the clavicle with extraosseous extension.

Intraosseous lipomas are rare primary benign bone tumors which present with highly nonspecific radiographic features that may lead to equivocal diagnoses. Advanced imaging studies such as MRI with and without contrast and, in some selected cases, tissue sample analyses are required in the diagnostic pathway. Here we describe the second case in the literature of an intraosseous lipoma of the clavicle and the first with extraosseous extension. Subsequent to histologic confirmation the lesion was monitored with clinical and radiologic evaluation.

Metastatic vertebral lesion mimicking an atypical hemangioma with negative 18F-FDG positron emission tomography-computed tomography.

Atypical hemangiomas of the spine can mimic metastatic lesions on magnetic resonance imaging, therefore making this distinction is a diagnostic challenge. In most cases, this conundrum can usually be solved with positron emission tomography/computed tomography images, because hemangiomas do not usually present with increased uptake while metastatic lesions do. Here we present a case of a patient with a unique diagnosis, myxoid liposarcoma, in which the vertebral metastatic lesion did not present with increased uptake in positron emission tomography/computed tomography scans. While keeping the imaging particularity of this rare sarcoma in mind, proceeding with a biopsy when the suspicion of metastasis remains high will help elucidate the diagnosis and allow for proper management.