[Treatment of malignant or aggressive bone tumors with microwave induced hyperthermia]

Limb-sparing procedures have been well established for dealing with malignant bone tumors. Unfortunately, these procedures have different problems. We used an alternative operation combined with microwave-induced hyperthemia to modify the surgical methods. Thermotherapy with microwave intracorporeal irradiation was used to treat 112 patients with bone tumors. In this series, 79 had malignant tumors and 33 aggressive benigh tumors. Postoperatively, immune therapy was carried out regularly. The patients immunologic functions were monitored by assay of the subpopulation of T cells, IL-2 and sIL-2R (soluble IL-2 receptor). Follow-up varied from 3 to 50 months (mean 23 month) s. Excluding 5 patients with malignancy in the vertebrae treated for palliation, 107 were evaluated by oncological and orthopedic criteria. 10 patients had local recurrence and required amputation. The remaining 97 had excellent local control. In 12 of the 74 patients with malignancy of the extremities, lung metastasis occurred 4 months to 2 years after surgery. Pathological fracture occurred at devitalized bone in 8 patients. In 29 out of 40 tumor-free cases followed for more than 2 years, the knee joints functioned properly with almost full range of motion. Single photon emission computered tomography (SPECT) study revealed revascularization of the devitalized tumor bearing bone segment could accomplish in one year or more. The immune state was improved after thermotherapy plus immunotherapy in the majority of patients. These results indicated that the use of microwave hyperthermia and adjuvant immunotherapy in the surgical treatment of bone tumors can be considered a definitive procedure, which is safe and well-tolerated.