Effect of radiofrequency hyperthermia and chemotherapy on primary and secondary hepatic malignancies when used with metronidazole.

Hyperthermia is selectively toxic to neoplastic tissue. Since August 1981, 357 patients with incurable tumors in various body areas have been treated with chemotherapy and radiofrequency hyperthermia (RFHT) with adjuvant metronidazole at this center. Of this group, the cases of 102 patients with hepatic tumors are reported here. Patients received one to ten treatment courses, each course consisting of two to five daily RFHT sessions. Systemic temperature rose 0.6 +/- 0.3 degrees C during treatment, and tumor core temperature (measured by percutaneous transhepatic thermistor) reached 39.5 +/- 1.2 degrees C in 38 monitored patients. Results have been encouraging; in particular, among 15 patients with newly diagnosed colorectal metastases limited to the liver (and as yet untreated for their secondary disease), there has been objective partial tumor regression in 66.7%. Side effects have been few. Skin burns and subcutaneous fat necrosis were seen in 3.9% and 13.7% of patients, respectively. Tumor temperature is difficult to measure reliably and does not correlate with machine power or tumor response. A phase III trial is currently underway to determine the efficacy of RFHT and chemotherapy for patients with hepatic metastases from colorectal adenocarcinoma.