Search Results (5)

Background/Objectives: Glioblastoma (GBM) is the most common primary malignant central nervous system tumor, accounting for 50.9% of malignant CNS diagnoses and carrying a median survival of 15 months despite maximal standard therapy. High recurrence rates are driven by residual infiltrative tumor cells at the resection margin. Fluorescence-guided surgery (FGS) has emerged as a key innovation to improve intraoperative tumor visualization and maximize the extent of resection (EOR). This review examines the historical development, current clinical applications, and future directions of FGS in GBM surgery. Methods: A comprehensive literature review was conducted, covering the evolution of fluorophores (fluorescein, indocyanine green [ICG], and 5-aminolevulinic acid [5-ALA]), visualization technologies (wide- and narrow-field modalities), therapeutic adjuncts (photodynamic and sonodynamic therapies), and clinical adoption patterns and outcomes. Results: Early intraoperative fluorescence using fluorescein dates to 1947. ICG angiography has broad surgical utility, while 5-ALA received FDA approval in 2017, with phase III trials demonstrating gross total resection rates of 65% versus 36% with white-light surgery. Adjunct technologies—3D exoscopes, FGS-compatible loupes, and quantitative spectroscopy probes—enhance detection of residual tumor. Preliminary studies of intraoperative photodynamic and sonodynamic therapies show feasibility and potential survival benefits. Global adoption of 5-ALA FGS exceeds 75% among surveyed neurosurgeons. Conclusions: FGS significantly improves EOR in GBM surgery, translating into better patient outcomes. Ongoing clinical trials and technological refinements—novel fluorophores, quantitative imaging, and therapeutic applications—promise to further optimize tumor visualization and treatment. Full article

Maximal safe surgical resection is the gold standard in brain tumor surgery. Fluorescence-guided surgery (FGS) is one of many intraoperative techniques that have been designed with the intention of accomplishing this goal. 5-aminolevulinic acid (5-ALA) is one of the main fluorophores that facilitates FGS in neurosurgical oncology. Multiple different types of brain tumors can take in and metabolize 5-ALA into protoporphyrin IX (PpIX) through the mitochondria heme biosynthesis pathway. PpIX then selectively accumulates in brain tumor cells due to decreased ferrochelatase activity and emits red fluorescence (630–720 nm) when excited with blue light (375–440 nm). This mechanism allows neurosurgeons to better visualize tumor burden and increase extent of resection while preserving non-cancerous brain parenchyma and, specifically, eloquent white matter tracts, if combined with mapping techniques, thereby minimizing morbidity while improving survival. While 5-ALA use is well established in the treatment of high-grade gliomas, its applicability in recurrent high-grade and non-enhancing IDH-mutant low-grade gliomas, as well as non-glial tumors, is less established or limited by certain features of their cellular and molecular biology. This review aims to discuss the current landscape of 5-ALA utility across the diverse range of brain tumors, practical considerations that optimize its current use in neurosurgery, modern clinical limitations of 5-ALA, and how its application can be expanded by combining its use with other techniques that overcome current limitations. Full article

Background: The objective in epithelial ovarian cancer is to reach maximal cytoreduction with no visible residual tumor. Tumor detection during cytoreductive surgery depends on visual inspection, palpation, or blind biopsy, methods that lack reliability for identifying microscopic disease. Although the importance of microscopic disease in epithelial ovarian cancer is controversial, it may harbor chemoresistant cells and explain the high recurrence rates. Fluorescence-guided surgery (FGS) is an emerging approach. However, the potential in ovarian cancer remains underexplored; the majority of the existing evidence pertains to gastrointestinal tumors and a limited group of ovarian cancer patients. Their comparative effectiveness is still uncertain. Objective: To systematically review and evaluate the role of fluorescence-guided surgical techniques in detecting microscopic disease in ovarian cancer and compare their efficacy to total peritonectomy. Data Sources: A systematic search was made in three databases (PubMed, Web of Science, and Embase). The search was conducted from 1975 to 2024, including randomized controlled trials, observational studies, and conference abstracts in the last 25 years. Study Selection: Clinical studies published in English involving ovarian cancer patients undergoing FGS or total peritonectomy were included. Case reports, reviews, animal studies, and studies involving mixed cancer populations without ovarian cancer-specific data were excluded. Two independent reviewers screened 631 studies, yielding 12 eligible studies for final analysis. Data Extraction and Synthesis: Data were extracted and synthesized in accordance with PRISMA and MOOSE guidelines, using random-effects models for independent analysis. Sensitivity, specificity, positive predictive value (PPV), and odds ratios (ORs) were grouped, accompanied by subgroup analyses based on the fluorescence agent employed. For quality assessment, we utilized the NIH quality tool. Main Outcome(s) and Measure(s): The primary outcome was the rate of change in surgical management due to fluorescence guidance or total peritonectomy. Secondary outcomes comprised lesion-level sensitivity, specificity, and PPV. Safety outcomes included adverse events associated with fluorescence agents. Results: There were 12 studies involving 429 ovarian cancer patients. FGS improved the detection of microscopic disease compared to standard visualization methods, with a pooled sensitivity of 0.77. Folate receptor-targeted agents had high sensitivity (84%) but low specificity (26%). Aminolevulinic acid (5-ALA) showed superior diagnostic accuracy with a sensitivity of 84% and a specificity of 96%. Total peritonectomy showed no significant advantage over FGS for detecting microscopic disease. The adverse events were mild, with no serious events reported. We observed a high heterogeneity across studies and methodologies. Conclusions and Relevance: Fluorescence-guided surgery utilizing fluorescence tracers demonstrates potential in improving the detection of microscopic disease and may change surgical management in epithelial ovarian cancer, particularly with 5-ALA. Variability in performance and limited data on survival outcomes necessitates additional research. Total peritonectomy does not offer further advantage in the detection of microscopic disease. Future trials should focus on standardizing methodology and evaluating the effects of microscopic disease removal on survival outcomes. Registration: The study was registered to PROSPERO as CRD42024578274. Full article

Glioblastoma multiforme (GBM) is a fatal brain tumor without effective drug treatment. In this study, we highlight, for the first time, the contribution of chromatin remodeling gene Lysine (K)-specific demethylase 5C (KDM5C) in GBM via an extensive analysis of clinical, expression, and functional data, integrated with publicly available omic datasets. The expression analysis on GBM samples (N = 37) revealed two informative subtypes, namely KDM5C^High and KDM5C^Low, displaying higher/lower KDM5C levels compared to the controls. The former subtype displays a strong downregulation of brain-derived neurotrophic factor (BDNF)—a negative KDM5C target—and a robust overexpression of hypoxia-inducible transcription factor-1A (HIF1A) gene, a KDM5C modulator. Additionally, a significant co-expression among the prognostic markers HIF1A, Survivin, and p75 was observed. These results, corroborated by KDM5C overexpression and hypoxia-related functional assays in T98G cells, suggest a role for the HIF1A-KDM5C axis in the hypoxic response in this tumor. Interestingly, fluorescence-guided surgery on GBM sections further revealed higher KDM5C and HIF1A levels in the tumor rim niche compared to the adjacent tumor margin, indicating a regionally restricted hyperactivity of this regulatory axis. Analyzing the TCGA expression and methylation data, we found methylation changes between the subtypes in the genes, accounting for the hypoxia response, stem cell differentiation, and inflammation. High NANOG and IL6 levels highlight a distinctive stem cell-like and proinflammatory signature in the KDM5C^High subgroup and GBM niches. Taken together, our results indicate HIF1A-KDM5C as a new, relevant cancer axis in GBM, opening a new, interesting field of investigation based on KDM5C as a potential therapeutic target of the hypoxic microenvironment in GBM. Full article

Glioblastoma (GBM) is the most aggressive adult brain tumour with a dismal 2-year survival rate of 26–33%. Maximal safe resection plays a crucial role in improving patient progression-free survival (PFS). Neurosurgeons have the significant challenge of delineating normal tissue from brain tumour to achieve the optimal extent of resection (EOR), with 5-Aminolevulinic Acid (5-ALA) the only clinically approved intra-operative fluorophore for GBM. This review aims to highlight the requirement for improved intra-operative imaging techniques, focusing on fluorescence-guided imaging (FGS) and the use of novel dyes with the potential to overcome the limitations of current FGS. The review was performed based on articles found in PubMed an.d Google Scholar, as well as articles identified in searched bibliographies between 2001 and 2022. Key words for searches included ‘Glioblastoma’ + ‘Fluorophore’+ ‘Novel’ + ‘Fluorescence Guided Surgery’. Current literature has favoured the approach of using targeted fluorophores to achieve specific accumulation in the tumour microenvironment, with biological conjugates leading the way. These conjugates target specific parts overexpressed in the tumour. The positive results in breast, ovarian and colorectal tissue are promising and may, therefore, be applied to intracranial neoplasms. Therefore, this design has the potential to produce favourable results in GBM by reducing the residual tumour, which translates to decreased tumour recurrence, morbidity and ultimately, mortality in GBM patients. Several preclinical studies have shown positive results with targeted dyes in distinguishing GBM cells from normal brain parenchyma, and targeted dyes in the Near-Infrared (NIR) emission range offer promising results, which may be valuable future alternatives. Full article