THE ROLE OF AGE AND TUMOR GRADE IN THE CHOICE OF FRACTIONATION REGIMEN IN PATIENTS WITH HIGH-GRADE GLIOMAS
There are currently no conventional guidelines for radiotherapy in gliomas. The treatment program is mainly formed in accordance with tumor morphology and the golden standard of irradiation is still the traditional mode of fractionation with a single focal dose of 2 Gy and total focal dose (TFD) of 60 Gy. In this report the treatment results of 396 patients with morphologically verified grade 3-4 malignant brain tumors receiving conventional irradiation regimen and irradiation by medium-sized fractions were analyzed to form institutional guidelines. The standard fractionation mode with a single focal dose of 2 Gy is preferable in patients with grade 3 glioma or elderly patients (over 60 years). TFD increase to 60-62 Gy in grade 4 gliomas and 54-56 Gy in grade 3 gliomas grants a significant improve in overall survival. An increase of a single irradiation fraction to 3 Gy may be used for patients younger than 60 years. In these cases it is advisable to use the TFD of 45 Gy or more (TFD of equivalent regimen with a dose greater than 54 Gy). The mentioned fractionation regimens could be recommended for the use in clinical practice to improve the results of high-grade gliomas treatment.