Intraarterial infusion chemotherapy and conformal radiotherapy for cancer of the mouth: prediction of the histological response to therapy with magnetic resonance imaging

Background: Although intraarterial chemotherapy has been used to treat head and neck cancers, some cases have shown poor response. If we can predict the response to this therapy on MRI, individual treatment plans may be altered to the most appropriate form of treatment. Purpose: To evaluate whether MRI can predict the histological response to preoperative chemoirradiation in patients with cancer of the mouth. Material and Methods: This study comprised of 29 consecutive patients with 30 oral cancers. All patients underwent tumor resection after intraarterial infusion chemotherapy and conformal radiotherapy. We compared the margin of the tumor, the presence of bone invasion, tumor area, and volume on pre- and post-treatment MRI with histological responses. Results: Eighteen lesions showed an excellent response, nine exhibited a good response, and three a poor response. Only the tumor area on pretreatment T1-weighted images and the tumor area and volume on pretreatment enhanced T1-weighted images were significantly correlated with the histological response ( P = 0.039, 0.008, and 0.016, respectively); smaller cancers showed better responses. The other factors were not significantly correlated with the histological responses. Conclusion: MRI parameters, excluding initial tumor area and volume, were not predictive of the histological response of oral tumors to preoperative treatment.