[Interstitial boost and altered fractionation as novel approaches to dose escalation in the radiotherapy of glioblastoma multiforme].
BACKGROUND
The practice of image-based three dimensional treatment planning and conformal radiotherapy techniques give the opportunity to elaborate optimal treatment forms for primary brain tumours.


OBJECTIVE
The authors examined the effect of two novel dose escalation methods on glioblastoma patients.


METHODS
In nine cases they treated T1 tumours with single HDR-AL boost of 10-12 Gy dose following the conventional fractionated 60 Gy external beam radiotherapy. In fifteen patients with T2-4 tumours an intensified, hypofractionated regimen with 2.25-2.5 Gy daily and 60 Gy total dose was applied. All the treatments were carried out with image-based conformal methods.


RESULTS
Majority of patients endured treatments without neurological deterioration. Transient neurotoxiticy was noticed in one and two cases, respectively. The median survival times (MST) were found to be 17 months (range: 9-25) and 12 months (range: 6-38) in the two groups, respectively. With respect to all patients, the MST was 13 months, while this value in the conventional treatment is generally considered to be 9-10 months. All the three patients who survived more than 18 months was treated with temozolamide chemotherapy as well.


CONCLUSIONS
Based on own experience and current knowledge of authors, it seems reasonable to apply higher biological dose focal radiotherapy and chemotherapy in case of glioblastoma patients with better prognosis. To define the optimal treatment regimens randomised clinical trials should be executed.
Mangel
László
L
Országos Onkológiai Intézet, Sugárterápiás Osztály, Budapest. mangel@oncol.hu
Julow
Jenö
J
Major
Tibor
T
Hável
János
J
Lövey
József
J
Viola
Arpád
A
Somogyi
András
A
Németh
György
G
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001918:Brachytherapy / Q000379:methods; D019583:Dose Fractionation, Radiation; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D016019:Survival Analysis; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome