A novel combined radiological method for evaluation of the response to chemotherapy for primary bone sarcoma

In the treatment of bone sarcoma, evaluation of chemotherapeutic effects is extremely important. In this study, we compared radiological evaluations and histological response, and developed a combined radiological scoring system for assessing the response to chemotherapy.

A total of 79 patients with primary bone sarcomas were examined by X-ray photography (Xp), angiography, MRI, 201Tl scintigraphy (Tl) and 99mTc-MIBI scintigraphy (MIBI) to evaluate their response to preoperative chemotherapy. Patients were classified as responders and non-responders according to radiological images. All resected tumors were evaluated histologically and classified as a good response (≥90% necrosis) or a poor response (≤90% necrosis). The sensitivity, specificity, accuracy, and kappa values in radiological evaluation were calculated. Furthermore, we developed a combined radiological scoring system that correlated the results of radiological images with histological response.

Sensitivity, specificity, and accuracy were 90.9%, 38.2%, and 67.5% (K = 0.31), respectively, for Xp; 91.7%, 33.3%, and 66.7% (K = 0.27) for angiography; 81.0%, 67.6%, and 75.0% (K = 0.49) for MRI; 78.9%, 72.4%, and 76.1% (K = 0.51) for Tl; 85.3%, 69.2%, and 78.3% (K = 0.55) for MIBI; and 93.3%, 76.5%, and 86.1% (K = 0.71) for combined radiological scoring.

Combined radiological evaluations showed high correlation with histological response for assessing the effects of chemotherapy.