MRI examination of resected malignant bone tumor can be an option for assessment of the osseous surgical margin

Abstract

OBJECTIVE: Confirming the surgical osseous margin of a resected malignant bone tumor macroscopically before reconstruction with a prosthesis is ideal. However, making the cut-surface of the femur specimen during surgery is difficult because of the hard bone tissue. In order to resolve this problem, the possibility of intraoperative MRI was considered. METHODS: MRI was performed at the surgical unit for five malignant femoral bone tumors that included two osteosarcomas and one undifferentiated high-grade sarcoma, and two metastatic tumors immediately after the tumor resection. The specimens were prepared in plastic containers with saline. RESULTS: The osseous surgical margins were confirmed to be those planned pre-operatively in all cases without metal-induced artifacts. The T₁ weighted image (WI) was useful for evaluation of the osseous surgical margin, whereas the T₂WI was useful for confirmation of extraosseous soft-tissue. CONCLUSION: The MRI was performed post-operatively as a preliminary evaluation of the technique. However, a limited sequence (i.e. coronal T₁WI) with short examination time could be performed during surgery for the sole purpose of assessing the osseous margin. ADVANCES IN KNOWLEDGE: MRI examination of a resected malignant bone tumor specimen has not been reported, and can be an option for assessment of the osseous surgical margin.