**Acknowledgements**

and risky for the patient. Considering these data, we conducted a study simulating radiofrequency deep LHT using a realistic bioequivalent phantom. Results of thermometry showed that the temperature in the normal brain substance and cerebrospinal fluid did not exceed the physiologic parameters. The rise in the tumor temperature enhanced the efficacy of radio-

Several clinical studies on transcranial radiofrequency hyperthermia for relapsed malignant brain tumors showed a low frequency of objective response (from 7 to 25% of cases) and the median overall survival time of 6–9 months after the onset of hyperthermia [84–86]. It was difficult to determine the effectiveness of treatment, since there were no data on the overall

A preliminary analysis of the results of this uncontrolled cohort clinical trial showed that at a median follow-up of 12 months, the median progression-free survival was 9.6 months in patients who received TCRT (CI 95%: 7.2–19.0 months). These results were better than those described in the randomized study conducted by Stupp [30], who reported that the median disease-free survival time was 6.9 months (95% CI: 5.8–8.2 months) and 7.1 months (95% CI: 5.9–8.2 months) in GBM patients treated with Stupp regimen and tumor-treating fields, respectively [30, 37]. The median overall survival time of patients included in the study was 23.4 months. However, the result was not statistically significant because the median follow-up was

Given a small number of patients included in the study, the evaluation of molecular-genetic prediction factors (IDH mutations and MGMT methylation) was important to avoid errors associated with a disproportionate number of patients with a favorable prognosis. The molecular-genetic features of tumors in patients enrolled in the study could not be the cause of improved survival. However, the study demonstrated a high frequency of subtotal tumor

Since radiofrequency hyperthermia was administered locally, an increase in the systemic side effects of chemotherapy compared with the frequency described in the population was not determined. The appearance of neurologic toxicity during chemotherapy with temozolomide not described in the previous studies [30] was more likely to be associated with an increase in edema and ischemic disorders. This was confirmed by the fact that neurological toxicity was mainly observed during the second course of chemotherapy, when external beam radiation

Concurrent hyperthermia and chemoradiotherapy did not result in an increased frequency of local injuries associated with transcranial local radiofrequency hyperthermia [79]. However, it is necessary to pay attention to the fact that during TCRT, one patient developed a fistula in the area of a postoperative scar, which indicated an impairment of reparative processes.

Preliminary results of the analysis of 30 patients with supratentorial newly diagnosed glioblastoma who received adjuvant thermochemoradiotherapy using transcranial radiofrequency

dose accumulated. However, none of the patients had evidence of ischemic stroke.

therapy [83].

up of 12 months.

**4. Conclusion**

survival from the time of surgical treatment.

178 Glioma - Contemporary Diagnostic and Therapeutic Approaches

resections, which was a negative predictor factor [1].

The work has been financially supported by the Fundamental Research Program of the Russian Academy of Sciences, project No. 093.
