Glioblastoma multiforme – stereotaxic radiotherapy brings promising results?

cancer cellGlioblastoma multiforme are tumours of especially bad prognosis. The average survival time of the patients is about 4 to 16 months depending on used treatment and predictors. Infiltrating character and the lack of effective treatment methods are the cause of disease process recurrence in 90% of the patients. It is diagnosed after about 4 months from recognition of the disease. Similarly as in the case of original change, many methods of tumour treatment involving surgery, radiotherapy, systemic treatment and their combination are introduced. However, research on introduction of other treatment procedures continues.

One of the methods which brings promising results is stereotaxic radiotherapy in the form of stereotaxic radiosurgery SRCH or stereotaxic fractionated radiotherapy SRF. Many research concerning the use of this method in recurrence of glioblastoma multiforme had been conducted in the world. They have shown that it significantly prolongs the life of the patients with recurrence of the disease.

Advantage of stereotaxic radiotherapy is precise radiation of tumour area with high dose and simultaneous protection of adjacent brain structures by significant decrease of the dose beyond target size. It is vital because of the fact that the most of glioblastoma multiforme patients underwent postoperative brain radiotherapy. Doses used during this procedure are usually tolerance doses of particular brain structures thus making another radiation impossible.

Effective use of stereotaxic radiotherapy needs strict cooperation of specialized team – neurosurgeon, radiotherapist, clinical oncologist and medical physicist. In order to precisely radiate while planning the treatment, the patients are immobilized. Their heads are placed in special stereotaxic frame which is fixed into the skull under regional anesthesia or in immobilizing masks. After performing location tomography gross tumour volume (GTV) is defined with a small (1-3 mm) margin of planned target volume and borders of critical organs. Then with the use of computer planning systems the number, shape and other parameters of radiation beams are defined in order to provide high and homogenous dose in the tumour area. Gamma radiation, X radiation and protons are used for this procedure. With the use of SRCH in the treatment of glioblastoma multiforme recurrence after primal ablation and conventional radiotherapy, the dose of 15-16 Gy on about 10ml of tumour volume is used. In SRF total doses of 35-36 Gy in fractions of 3,5-5 Gy are used for 14-15ml of tumour volume.

In conducted research on the use of stereotaxic radiotherapy as the treatment method of glioblastoma multiforme recurrence the scientists obtained total average survival of 9,3-10 months and survival free from progression of 4,6-5 months. The survival time from the recognition of the disease was 21 months on average.

Stereotaxic radiotherapy is a method of high efficiency, however its use involves numerous complications. The earliest and most frequent side effects are nausea, torsions, headaches, drowsiness, fever and worsening of neurological condition observed after radiation. Late complications are radionecrosis and phalacrosis in the place of radiation. According to Kong et.al., from the University in Korea radionecrosis, which is the most severe complication, occurred in 22 out of 114 radiated patients.

The use of stereotaxic radiotherapy is effective and safe course of action in glioblastoma multiforme recurrence. Its unquestionable advantages are: short time of treatment, possibility of usage in patients who were radiated with high total doses, safety and prolongation of the patients’ survival time with simultaneous improvement of neurological conditions in some of them.

Written by: Aleksandra Jarocka MD, Anna Brzozowska PhD

Source:
1.Fijuth J, Nowotwory ośrodkowego układu nerwowego. Zalecenia postępowania diagnostyczno – terapeutycznego w nowotworach złośliwych 2011 rok. Pod red. Krzakowski M. tom I, Gdańsk Via Medica 2011.
2.Combs i wsp., Stereotactic Radisurgery ( SRS) Treatment Option for Recurrent Glioblastoma Multiforme ( GBM), Cancer 2005, 15;104(10):2168-73.
3.Koga Saito, Efficacy and Limitations of Stereotactic Radiosurgery in the Treatment of Glioblastoma, Neurol Med Chir 2012, 52; 548-552.
4.Thumma i wsp., Long-Term Survival after Gamma Knife Radiosurgery in a Case of Recurrent Glioblastoma Multiforme: A Case Report and Review of the Literature, Neurosurg rev, 2009,32; 417-424.
5.Vordermark i wsp., Hypofractioned stereotactic re- irradiation: treatment option in recurrent malignant glioma, BMC Cancer, 2005, 30;5:55.
6.Kong i wsp., Efficacy of Stereotactic Radiosurgery as a Salvage treatment for Recurrent Malignant Gliomas, Cancer, 2008;112(9):2046-51.
7.Shannon i wsp., Hypofractionated Stereotactic Radiation Therapy: An Effective Therapy for Recurrent High-Grade Gliomas, Journal of Clinical Oncology, J Clin Oncol, 2010;28(18):3048-53.

Would you like to know more? Watch on Medtube.net: Glioblastoma multiforme – histopatology – brain

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