Radiofrequency Hyperthermia for Malignant Brain Tumors: Preliminary Results of Clinical Trials

Abstract

Local hyperthermia by 13.56-MHz radiofrequency (RF) capacitive heating was evaluated in 16 patients with malignant brain tumors. Intracranial heating during operation was performed in 4 patients. RF applicators with a cooling system were placed on the cerebral convexity and medial brain surface with the tumor between them. RF power was controlled to maintain the brain temperatures under 40 degrees C. Under this condition, the highest temperature of each tumor varied from 44 to 49 degrees C. After heating for about 60 minutes, 2 tumors showed regression on computed tomographic (CT) scans. Extracranial heating was performed in 12 patients with cerebral glioblastoma. RF applicators were placed on the lateral sides of the scalp and applied to diametrically opposite sides of the tumor. To avoid the influence of the skull on RF conduction, we performed a bilateral craniectomy slightly larger than the applicator at the initial operation. Heating was performed for approximately 60 minutes at each session and was repeated twice a week for a total of 4 to 10 times in combination with radiation and ACNU chemotherapy. No anesthetic agent was used during heating. Brain temperatures were maintained under 42 degrees C. The scalp under the applicators remained at 28-35 degrees C during heating, and no heat injury of the scalp was observed after repeated heating. The highest temperatures of the tumor or cavity after tumor removal were 45-46 degrees C in 3 cases, 43-44 degrees C in 3 cases, 42-43 degrees C in 4 cases, and 40-41 degrees C in 2 cases, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Selective Ablation of Porcine and Rabbit Liver Tissue Using Radiofrequency: Preclinical Study

“…Tanaka et al [5] showed that RF capacitive heating can be applied safely to treat a malignant tumor in the human cerebrum. In neurosurgery, repeated RF heating was found to be practical and useful.…”

“…The advantage of RF catheter ablation is its ability energy to a discrete area without stimulating muscles or nerves [2]. Recently, RFA for a larger part of the visceral organs or intra-abdominal tumors has been reported [3][4][5][6][7][8]. The development of bipolar and multiple-electrode RFA probes Nakagawa et al has enabled the creation of much larger lesions.…”

“…LeVeen et al [3] and Storm et al [4] reported that RF therapy produced tissue necrosis or substantial regression of cancer in patients. Tanaka et al [5] showed that RF capacitive heating can be used safely to heat malignant tumors in the human cerebrum. There have been many reports on the histological conformation of the RFA field in vivo [9][10][11].…”

Targeting chemotherapy for malignant brain tumor using thermosensitive liposome and localized hyperthermia

“…For the past 10 years, we have been developing hyperthermic therapy for malignant brain tumors 30 and have recently completed a new technique using an RF antenna which can be inserted into optional regions of the brain with a stereotactic apparatus. 28 This antenna can apply sufficient regional hyperthermia without causing adverse reactions, even if the brain tumor exists in an eloquent area.…”

Hyperthermia Promotes Apoptosis and Suppresses Invasion in C6 Rat Glioma Cells

“…There has been much interest in studying the effects of heat on the brain (Sminia et al, 1994;Haveman et al, 2005). A number of well-localized, mainly interstitial, invasive hyperthermia combination therapies have been applied for gliomas (Tanaka et al, 1987;Sneed et al, 1991Sneed et al, , 1992Sneed et al, , 1998Stea et al, 1990Stea et al, , 1994Moran et al, 1995;Fiorentini et al, 2006;Silva et al, 2011).…”