First experience of intraoperative radiation therapy in cerebral high grade glioma in Iran: a report of three cases and literature review

Introduction: Among the high grade cerebral gliomas, Glioblastoma multiform for instance, would be the main pattern of local recurrence causes clinical deterioration and deaths. This has observed 2 - 3 cm upon the initial lesion. During the period of 2 - 4 weeks post-surgery, remaining tumor cells have re-grown until radiochemotherapy has initiated. So it has seemed clear that improved local control could hopefully translate into improved survival. As a matter of fact, mass reduction has insufficiently achieved in almost every case of GBM as that the tumor cell number has not fallen below a "threshold" that tumor control might achieve by the host immune system. Intraoperative Radiation therapy has been one of those add-on therapies, which has performed during or directly after resection and cleared the tumor cavity from microscopically remaining cells. Although IORT has presented a novel and feasible principle, the method faced a number of technical and geometrical errors and limitations, which has decreased its potential in the reports of previous studies. Examples could be mentioned as incomplete target volume coverage that seemed as the greatest influence on survival, due to irradiation with an inadequate electron cone size, due to angle errors, or inadequately low energies. In contrast to the previously used forward-beaming electron cones, spherical irradiation sources were specifically attractive in brain tumor IORT, even in post resection cavities with normal complex shapes

Case Presentation: We have been reporting 3 cases of high grade gliomas, one recurrent GBM, one primary glioma grade III, and the last one recurrent Rhabdoid GBM, which have been fulfilling our entrance criteria of IORT procedure, by using spherical applicators, which has been increasingly discussed in recent studies

Conclusions: It was the first experience of intraoperative radiation therapy for cerebral malignant tumours in Iran. Finally, we had a brief overview on the past and present IORT strategies in the treatment of GBM

Diffusion tensor tractograghy can affect treatment strategy to remove brain occupying mass lesions

Radical resection of a pathological lesion along with the preservation of eloquent cerebral tissue is the principle goal of neurosurgery. Brain lesions are usually diagnosed by conventional magnetic resonance imaging [MRI], but this method is unable to describe the relationship between lesions and neighboring specific white matter [WM] tracts. Diffusion tensor tractograghy [DTT] is a new sophisticated imaging modality to reveal the neural fibers and their relationships with lesions. In the current study we assess that how diffusion tensor tractograghy can affect on treatment planning in patients afflicted by different types of brain lesions. In this prospective observational study, eight patients with brain mass lesion underwent conventional brain MRI pulse sequences and DTT imaging with 1.5 Tesla system using 64 independent diffusion encoding directions between December 2011 to January 2013.Acquired images were assessed by the neuroradiologist and neurosurgeon. Finally, the treatment strategies were compared using data before and after the tractograghy. The treatment strategy in six patients changed from radiotherapy into the craniotomy by using tractograghy data, in one patient changed from radio surgery to craniotomy and in one patient, neurosurgeon preferred to avoid operation. As we can infer from this study, based on the tractograghy results, the treatment technique may be changed, and the treatment plan could be devised with more accuracy and in case of surgery, may lead to less post-operative neurological deficits and better outcome results