Intracortical Bone Metastasis Mimicking Intracortical Osteoid Osteoma: A Case Report

tic processes involving bone. Most skeletal metastasis comes about from a hematogenous spread from an original tumor (1). The diagnosis of skeletal metastatic lesion is not generally difficult when multiple lesions are present and the clinical history is correlated with this. If the metastasis occurs in an unusual location as a single lesion, it is not easy to make a diagnosis. In some instances, skeletal metastases involve the cortex of long bones. Depending upon the size and exact location of the lesion, there may be either “endosteal” scalloping of the cortex from lesions seated in the medullary cavity, “subperiosteal” scalloping for periosteal metastases, or focal cortical defects from direct cortical metastases. Even in the cases with focal cortical defects, the lesion usually settles in the diaphysis of a long bone and this shows focal cortical bone destruction with a poorly defined margin, which may suggest a metastatic lesion (2). We present here a case of the intracortical bone metastasis in the greater trochanteric area of the right femur as an initial metastatic focus, and this was associated with excessive peritumoral edema that mimicked intracortical benign bony lesion. We also discuss the diseases that can be included in the differential diagnosis of this malady.