gms | German Medical Science

Objective: We investigated the effectiveness of a combined treatment of fractionated stereotactic radiotherapy in conjunction with a new intratumoral thermotherapy method using magnetic nanoparticles in patients with recurrent glioblastoma with respect to toxicity and survival outcome.

Methods: In a single-arm two-centre study, 59 patients with recurrent glioblastoma received neuronavigationally-controlled intratumoral injection of an aqueous dispersion of iron-oxide nanoparticles, which were subsequently heated in an alternating magnetic field. Treatment was combined with fractionated stereotactic radiotherapy applying a median dose of 30 Gy in conventional fractionation. Median time between primary diagnosis and first tumor recurrence was 8.0 months.

Results: Median overall survival after diagnosis of first tumor recurrence (OS-2) was 13.4 months (95% CI: 10.6–16.2 months). Median survival after primary tumor diagnosis (OS-1) was 23.2 months (95% CI 17.2–29.2 months). Only tumor volume at study entry was significantly correlated with OS-2 (p<0.01). No other factors – age, KPS or time to first tumor progression – had any significant prognostic value on OS-2. The side effects of the new therapeutic approach were moderate, and no serious complications were observed. Commonest were rise of body temperature, sweating, seizures and motor disturbances. However, in less than 5% of the patients, during thermotherapy neurological disorders occurred for the first time.

Conclusions: Thermotherapy using magnetic nanoparticles in conjunction with radiotherapy is safe in treatment of recurrent glioblastoma and results in a significantly longer median survival compared to conventional treatments in historical groups.