The field of neuro-oncology continues to evolve, with ongoing advances in technology and approaches aimed at improving the diagnosis and treatment of primary and metastatic brain and spine tumors. This progress is highlighted by the recent 2021 update of the World Health Organization Classification of Tumors of the Central Nervous System. This classification represents a significant step forward in how we classify and treat primary brain tumors, with the inclusion of molecular diagnostic criteria for many different tumor types representing a significant departure from the prior histopathology-based classification. A corollary of these more refined diagnostic criteria is the continued need to optimize and personalize diagnostic and therapeutic approaches for individual patients and tumors on the basis of the specific clinical, radiographic, histopathologic, and molecular criteria that most impact patient outcomes. The current issue of Neurosurgical Focus includes a wide variety of studies that address various aspects of the neurosurgical management of different diseases, tumor diagnosis and grading, clinical and molecular prognostic factors, and management of tumors with specific molecular alterations.
One theme of this issue is the use of novel and varied technologies to optimize extent of resection and patient outcomes. The approaches include the application of advanced imaging and/or preoperative and intraoperative mapping for neurosurgical planning and resection. Bennett et al. compared preoperative functional MRI and intraoperative direct electrical stimulation to functional cortical parcellation predicted by the Human Connectome Project. The role of preoperative mapping for localization of language areas in patients who are not eligible for awake craniotomy is discussed by Raffa et al. A similar topic in relation to children is addressed by Krieg et al., who describe the application of technologies including MRI tractography and navigated transcranial magnetic stimulation for preoperative identification of eloquent areas in younger children for whom functional MRI and direct intraoperative stimulation are not practical. The effect of technology-driven procedures is the topic of the study by Lu et al., who assessed the effect of MR-guided focused ultrasound thalamotomy on neuronal connectivity in a series of essential tremor patients.
Another important theme of this Neurosurgical Focus issue is the identification and application of prognostic factors for neurosurgical and treatment outcomes. Song et al. identified low preoperative serum prealbumin concentration as a significant prognostic predictor of surgical risk and intracranial infection in a large single-institution series of patients who underwent transsphenoidal surgery. Ueberschaer et al. describe a simple surgical approach for modification of pituitary adenoma transsphenoidal resection closure in patients identified as high risk for postsurgical CSF leak. Prediction of risk of postprocedural infection after placement of a pulse generator and deep brain stimulation electrodes is the question addressed by Chen et al., who utilized a large single-institution series to derive a predictive nomogram based on BMI, blood glucose, and albumin level. Similarly, Kassicieh et al. utilized a large national database to derive a novel preoperative risk model based on a combination of clinical and laboratory factors in order to predict risk of perioperative cerebral vascular accident after intracranial tumor resection. Pei et al. analyzed perioperative hormone levels along with other clinical factors to define a total hormonal rate predictive of risk for perioperative hypopituitarism. Lastly, in the area of prediction of functional recovery, Park et al. identified clinical and operation-related factors predictive of poor motor function recovery after metastatic epidural spinal cord compression.
On the topic of improving the diagnosis and treatment of primary CNS tumors, the current issue includes articles focused on different technological approaches to the intraoperative and/or molecular diagnosis of CNS tumors. Wadiura et al. explores the promising application of intraoperative stimulated Raman histology and compares the diagnostic and histopathologic yield of this technology with that of traditional frozen section and H&E histopathology. Bauman et al. reviews the exciting field of liquid biopsy in glioblastoma and discusses the potential uses and limitations of multiple biomarkers from blood, CSF, and extracellular vesicles.
The use of targeted therapies for CNS tumors harboring specific DNA alterations has been an area of active investigation, and evolving data are clarifying the opportunities and challenges in real-world applications. Leclair et al. describe their single-institution experience with a small series of pediatric low-grade glioma patients treated with targeted therapy for tumors harboring MAPK pathway activation, including BRAF and NF1 alterations. FGFR3-TACC3 fusion, which has been highlighted in recent years as a potential but rare alteration in gliomas, is the topic of the case series by McDonald et al. that highlights some of the heterogenous clinical and histological features of these tumors. Finally, Suman et al. describe histological and immunohistological features that can be used to stratify histologically grade 2 or 3 isocitrate dehydrogenase–mutant astrocytomas into high or low risk for CDKN2A loss in order to streamline and facilitate the optimal use of diagnostic resources for the identification of this important molecular grading criterion in this tumor group.
Overall, this collection of studies highlights the wide variety of approaches and technological developments that are rapidly advancing the neurosurgical management, diagnosis, and treatment of patients with primary and metastatic CNS tumors.
Dr. Colman is a consultant for Best Doctors/Teladoc, Orbus Therapeutics, Bristol Myers Squibb, Regeneron, and Novocure. Dr. Brastianos is a consultant for Advice Connect Inspire, Axiom Healthcare Strategies, Dantari, ElevateBio, Pfizer, Sintetica, SK Life Science, Voyager Therapeutics, Eli Lilly, Genentech, Merck, and Tesaro; receives speakers honoraria from Pfizer; and receives clinical or research support from Mirati, Eli Lilly, Merck, BMS, AstraZeneca, Genentech-Roche, Pfizer, and GlaxoSmithKline.
INCLUDE WHEN CITING DOI: 10.3171/2022.9.FOCUS22437.
Disclosures Dr. Colman is a consultant for Best Doctors/Teladoc, Orbus Therapeutics, Bristol Myers Squibb, Regeneron, and Novocure. Dr. Brastianos is a consultant for Advice Connect Inspire, Axiom Healthcare Strategies, Dantari, ElevateBio, Pfizer, Sintetica, SK Life Science, Voyager Therapeutics, Eli Lilly, Genentech, Merck, and Tesaro; receives speakers honoraria from Pfizer; and receives clinical or research support from Mirati, Eli Lilly, Merck, BMS, AstraZeneca, Genentech-Roche, Pfizer, and GlaxoSmithKline.