Glioblastoma multiforme: Molecular characterization and current treatment strategy (Review)

Abstract

Glioblastoma multiforme (GBM) is the most common and lethal malignant primary brain tumor. It is classified by the World Health Organization (WHO) in the group of diffusely infiltrating astrocytomas, representing up to 50% of all primary brain gliomas, and carries the poorest prognosis. Aberrant genetic events and signaling pathways have clearly demonstrated that GBM is highly anaplastic and a morphologically highly heterogeneous tumor. Understanding the genetic alterations, specific molecular biomarkers and proliferative pathways may promote therapeutic development for the management of GBM. Age, Karnofsky performance score, histology, position and the extent of tumor resection have been identified as potential prognostic factors for patients with GBM. In this study, we review the molecular characterization of tumor cells, the current standard of care for patients diagnosed with GBM, including gross or near-total resection of the tumor, followed by radiotherapy, stereotactic brachytherapy, chemotherapy and new targeted therapies. Thus, we conclude that multimodal approaches for the treatment of patients with GBM may significantly improve their prognoses.

Figure 1.

Imaging of a 58-year-old female who was admitted to our hospital with a 25-day history of headaches, nausea and vomiting, visual deficits and sporadic epilepsy. A nervous system examination revealed clear consciousness, but weakness and decreased visual acuity; decreased myodynamia, hyper-reflexia on the left side of her body, and a positive left Babinski’s sign. The KPS score was 50. Contrast-enhanced MR images: (A) axial and (B) saggital showing a large enhancing mass in the deep site of the right frontal lobe and involved to midline. Surrounding edema and the cerebral compression with midline shift are also evident. The lesion has a mixed signal with hyperintense or hypointense signaling on T1-weighted gadolinium-enhanced images. Given the signs of increased intracranial pressure and acute neurological deterioration caused by the space-occupying lesions, an instant craniotomy for tumor resection was performed and the tumor was completely removed. Histopathological examination confirmed the diagnosis of GBM.

Figure 2.

(A) Axial and (B) saggital T1-weighted MRI of the same female, 3 years after treatment, showing complete tumor disappearance. The patient received RT 2 weeks postoperatively, and then TMZ chemotherapy with oral administration 4 weeks postoperatively, and a maximum of three courses/year were delivered. The patient is alive and free of progression at the time of the most recent observation, 39 months following initial diagnosis.