Musculoskeletal neoplasms after intraarterial chemotherapy: correlation of MR images with pathologic specimens.

Abstract

The most accurate prognostic indicator in patients with musculoskeletal sarcomas is the percentage of tumor necrosis after intraarterial chemotherapy. Magnetic resonance (MR) imaging was evaluated to determine its ability to indicate the percentage of necrosis in musculoskeletal neoplasms after treatment. Fourteen patients with musculoskeletal neoplasms underwent treatment protocols including intraarterial chemotherapy (n = 14), radiation therapy (n = 6), and systemic chemotherapy (n = 14). All patients underwent MR imaging before and after treatment, and all underwent either limb salvage surgery (n = 8) or amputation (n = 6) within 1 week of the last MR examination. Standard unehanced spin-echo T1-, spin-density-, and T2-weighted MR sequences were used. The MR images were compared with the pathologic specimens. On T2-weighted images, the signal intensities of viable tumor, tumor necrosis, edema, hemorrhage, and necrosis overlapped. With the unenhanced spin-echo technique, MR imaging cannot be used to predict the percentage of tumor necrosis in musculoskeletal neoplasms after intraarterial chemotherapy.

Radiosurgery for Metastatic Spinal Tumors: Follow-Up MR Findings

“…T2 signal intensities were increased in 89.9% (types 2 and 3) of all lesions and mainly considered the result of tumor necrosis. But Sanchez et al 23 correlated pathologic specimens of primary musculoskeletal neoplasms after chemotherapy with MR images, and reported that areas of high signal intensity on T2WI corresponded to areas of residual viable tumor, tumor necrosis, edema, fibrosis, and hemorrhage. In our study, decreased but persistent contrast enhancement was observed in the area of increased T2 signal intensity.…”

Osteosarcoma after Preoperative Chemotherapy: Tissue Characterization with Specimen MR and the Role of Enhanced MR Imaging

“…In addition, only limited differentiation between group 2 (necrosis over 80%) and group 3 (viable tumor cells up to 95%) was possible ; this was because technical factors including window selection and volume averaging were involved. Thus tumor necrosis cannot be predicted on the basis of signal intensity alone, and because the appearances of viable tumor, necrosis, edema, fibrosis, granulation tissue, and hemorrhage overlap, changes in signal intensity do not reliably indicate the absence of active disease (5). Moreover, small clusters of active tumor cells were found in areas of dense reactive bones (7).…”

Femoral infarction following intraarterial chemotherapy for osteosarcoma of the leg: a possible pitfall in magnetic resonance imaging

“…Preoperative chemotherapy is used to reduce tumoral volume [9,10], allow limb salvage surgery, eradicate micrometastases, and test therapeutic efficacy [1,3,9]. The percentage of tumor necrosis induced by preoperative chemotherapy is one of the essential prognostic factors [3,9].…”

“…It induces effects on the tumor and also on surrounding normal tissues. These local undesirable effects on the normal tissues may be misdiagnosed as a tumoral progression under chemotherapy [7][8][9]. We report abnormal images with MRI examination appearing on the distal femur after intraarterial chemotherapy (IAC) for osteosarcoma of the tibia in one case, the fibula in the other.…”