Standard therapy for glioblastoma (GBM) is temozolomide (TMZ) administration, initially concurrent with radiotherapy (RT), and subsequently as maintenance therapy. The radiologic images obtained in ...this setting can be difficult to interpret since they may show radiation-induced pseudoprogression (psPD) rather than disease progression.
Patients with histologically confirmed GBM underwent radiotherapy plus continuous daily temozolomide (75 mg/m(2)/d), followed by 12 maintenance temozolomide cycles (150 to 200 mg/m(2) for 5 days every 28 days) if magnetic resonance imaging (MRI) showed no enhancement suggesting a tumor; otherwise, chemotherapy was delivered until complete response or unequivocal progression. The first MRI scan was performed 1 month after completing combined chemoradiotherapy.
In 103 patients (mean age, 52 years range 20 to 73 years), total resection, subtotal resection, and biopsy were obtained in 51, 51, and 1 cases, respectively. MGMT promoter was methylated in 36 patients (35%) and unmethylated in 67 patients (65%). Lesion enlargement, evidenced at the first MRI scan in 50 of 103 patients, was subsequently classified as psPD in 32 patients and early disease progression in 18 patients. PsPD was recorded in 21 (91%) of 23 methylated MGMT promoter and 11 (41%) of 27 unmethylated MGMT promoter (P = .0002) patients. MGMT status (P = .001) and psPD detection (P = .045) significantly influenced survival.
PsPD has a clinical impact on chemotherapy-treated GBM, as it may express the glioma killing effects of treatment and is significantly correlated with MGMT status. Improvement in the early recognition of psPD patterns and knowledge of mechanisms underlying this phenomenon are crucial to eliminating biases in evaluating the results of clinical trials and guaranteeing effective treatment.
Gliomas are molecularly heterogeneous brain tumors responsible for the most years of life lost by any cancer. High-grade gliomas have a poor prognosis and despite multimodal treatment including ...surgery, radiotherapy, and chemotherapy, exhibit a high recurrence rate. There is a need for new therapeutic approaches based on precision medicine informed by biomarker assessment and BRAF, a key regulator of MAPK signaling pathway, influencing cell differentiation, proliferation, migration and pro-tumorigenic activity, is emerging as a promising molecular target. V600E, is the most frequent BRAF alteration in gliomas, especially in pediatric low-grade astrocytomas, pleomorphic xanthoastrocytoma, papillary craniopharyngioma, epithelioid glioblastoma and ganglioglioma. The possible application of BRAF-targeted therapy in gliomas is continuously growing and there is preliminary evidence of prolonged disease control obtained by BRAF inhibitors in tumors harboring BRAF V600E mutation. The possibility of introducing targeted therapies into the treatment algorithm represents a paradigm shift for patients with BRAF V600E mutant recurrent high-grade and low-grade glioma and BRAF routine testing should be considered in clinical practice. The focus of this review is to summarize the molecular landscape of BRAF across glioma subtypes and the novel therapeutic strategies for BRAF V600E mutated tumors.
The aim of the present study was to evaluate factors predicting the recurrence pattern after the administration of temozolomide (TMZ), initially concurrent with radiotherapy (RT) and subsequently as ...maintenance therapy, which has become standard treatment for patients with newly diagnosed glioblastoma (GBM).
Ninety-five patients with newly diagnosed GBM were treated with RT plus TMZ (75 mg/m(2)/d) followed by maintenance TMZ cycles (150 to 200 mg/m(2) for 5 days every 28 days). Assessable MGMT methylation status and magnetic resonance imaging follow-up were mandatory in all cases.
After a median follow-up of 18.9 months (range, 6.6 to 44.8 months), 79 patients (83%) had recurrence: inside the RT field in 57 patients (72.2%), outside in 17 patients (21.5%), and at RT margin in five patients (6.3%). MGMT status was correlated with the site of recurrence, which occurred inside, or at the margin of, the RT field in 51 patients (85%) with MGMT unmethylated status and in 11 patients (57.9%) with MGMT methylated status (P = .01). Recurrences outside the RT field occurred after a longer time interval than those inside the RT field (14.9 v 9.2 months, P = .02).
After the administration of TMZ concomitant with and adjuvant to RT in patients with GBM, the pattern of, and time to, recurrence are strictly correlated with MGMT methylation status.
Meningiomas are the most common primary intracranial tumors. The majority of meningiomas are benign, but they can present different grades of dedifferentiation from grade I to grade III ...(anaplastic/malignant) that are associated with different outcomes. Radiological surveillance is a valid option for low-grade asymptomatic meningiomas. In other cases, the treatment is usually surgical, aimed at achieving a complete resection. The use of adjuvant radiotherapy is the gold standard for grade III, is debated for grade II and is not generally indicated for radically resected grade I meningiomas. The use of systemic treatments is not standardized. Here we report a review of the literature on the clinical, radiological and molecular characteristics of meningiomas, available treatment strategies and ongoing clinical trials.
The glioma-associated tumor microenvironment involves a multitude of different cells ranging from immune cells to endothelial, glial, and neuronal cells surrounding the primary tumor. The ...interactions between these cells and glioblastoma (GBM) have been deeply investigated while very little data are available on patients with lower-grade gliomas. In these tumors, it has been demonstrated that the composition of the microenvironment differs according to the isocitrate dehydrogenase status (mutated/wild type), the presence/absence of codeletion, and the expression of specific alterations including H3K27 and/or other gene mutations. In addition, mechanisms by which the tumor microenvironment sustains the growth and proliferation of glioma cells are still partially unknown. Nonetheless, a better knowledge of the tumor-associated microenvironment can be a key issue in the optic of novel therapeutic drug development.
The lack of significant improvement in the prognosis of patients with GB over the last decades highlights the need for innovative treatments aimed at fighting this malignancy and increasing survival ...outcomes. The results of the phase III clinical trial of DCVax-L (autologous tumor lysate-loaded dendritic cell vaccination), which has been shown to increase both median survival and long-term survival in newly diagnosed and relapsed glioblastoma, have been enthusiastically received by the scientific community. However, this study deserves some reflections regarding methodological issues related to the primary endpoint change, the long accrual period, and the suboptimal validity of the external control population used as the comparison arm.
Glioblastoma is an aggressive tumor and is associated with a dismal prognosis. The availability of few active treatments as well as the inexorable recurrence after surgery are important hallmarks of ...the disease. The biological behavior of glioblastoma tumor cells reveals a very complex pattern of genomic alterations and is partially responsible for the clinical aggressiveness of this tumor. It has been observed that glioblastoma cells can recruit, manipulate and use other cells including neurons, glial cells, immune cells, and endothelial/stromal cells. The final result of this process is a very tangled net of interactions promoting glioblastoma growth and progression. Nonetheless, recent data are suggesting that the microenvironment can also be a niche in which glioblastoma cells can differentiate into glial cells losing their tumoral phenotype. Here we summarize the known interactions between micro-environment and glioblastoma cells highlighting possible therapeutic implications.
Approximately 50% of glioblastomas (GBMs) are characterized by overexpression of the epidermal growth factor receptor (EGFR) and EGFR gene amplification. In approximately 25% of instances, ...constitutively activated EGFR mutants are present. These observations make EGFR-inhibiting drugs a logical approach for trials in recurrent GBM.
In a randomized, controlled, phase II trial, 110 patients with progressive GBM after prior radiotherapy were randomly assigned to either erlotinib or a control arm that received treatment with either temozolomide or carmustine (BCNU). The primary end point was 6-month progression-free survival (PFS). Tumor specimens obtained at first surgery were investigated for EGFR expression; EGFRvIII mutants; EGFR amplification; EGFR mutations in exons 18, 19, and 21; and pAkt. These results were correlated with outcome. Pharmacokinetic analysis was part of the study. RESULTS; Treatment was well tolerated in general; skin toxicity was the most frequent adverse effect of erlotinib. The 6-month PFS rate in the erlotinib arm was 11.4% (95% CI, 4.6% to 21.5%), and it was 24% in the control arm. Of all explored biomarkers, only low pAkt expression appeared to be of borderline significance to an improved outcome. None of the eight patients who had tumors with EGFRvIII mutant presence and PTEN expression had 6-month PFS. The use of enzyme-inducing anticonvulsants significantly increased erlotinib clearance, but pharmacokinetic findings were not related to outcome.
Erlotinib has insufficient single-agent activity in unselected GBM. No clear biomarker associated with improved outcome to erlotinib was identified.
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