Foundations of the Diagnosis and Management of Low-Grade Gliomas.

In the past, low-grade gliomas-World Health Organization (WHO) grade I and II tumors-were generally expected to have a much better prognosis than higher-grade (WHO grade III and IV) gliomas. However, diffuse gliomas (WHO grade II), unlike WHO grade I gliomas, are by definition infiltrative, limiting resection and potentially contributing to poor outcomes like those seen with malignant gliomas. Rapid progress in the understanding of the pathogenesis of these tumors indicates that specific molecular factors, especially isocitrate dehydrogenase mutation status and the presence or absence of the 1p/19q codeletion (deletion of the short arm of chromosome 1 and long arm of chromosome 19), are much more important than grade in determining prognosis and response to treatment. These molecular characteristics outweigh the histologic distinctions and have been quickly incorporated into the WHO classification of gliomas. Management of these tumors with surgery, radiation, and chemotherapy has similarly been transformed by these developments, highlighting the need for a customized approach for patients with low-grade gliomas.

Challenges in the Diagnosis and Management of Low-Grade Gliomas.

Low-grade gliomas are clinically challenging entities. Patients with these tumors tend to be relatively young at presentation, and lesions are often incidental findings or are identified because the patient presents with a seizure. Rapidly emerging and evolving molecular classifications of gliomas have influenced treatment paradigms. Importantly, low-grade gliomas can be classified on the basis of IDH mutation status, whereby low-grade astrocytomas harbor the IDH mutation, while oligodendrogliomas are defined by both IDH mutant status and 1p/19q co-deletion. Given the importance of molecular classification for diagnosis, treatment planning, and prognostication, tissue samples are necessary for proper management. Literature supports improved overall survival and outcomes with increased extent of resection for low-grade glioma. Awake craniotomies and resection of insular low-grade gliomas both have been demonstrated as safe and improve outcomes for patients with lesions located in eloquent areas. Given the younger age at diagnosis of these lesions compared with higher-grade gliomas, fertility, fertility preservation, and potential malignant transformation should be discussed with patients of childbearing age.

Acromegaly: Medical and Surgical Considerations.

Acromegaly results from excessive secretion of insulinlike growth factor-1 and growth hormone, which most commonly occurs because of pituitary somatotrophinoma. Diagnostic features of acromegaly include elevated insulinlike growth factor-1 and growth hormone; lesion on brain MRI; and clinically dysmorphic features, such as soft tissue swelling, jaw prognathism, and acral overgrowth. Transsphenoidal resection is the primary therapy for individuals with acromegaly, even in the cases where gross total resection is not possible because of parasellar extension and cavernous sinus involvement. For recurrent or persistent disease after resection, systemic medications and stereotactic radiosurgery are used.

Novel approaches to the management of patients with 5-15 brain metastases: a narrative review.

BACKGROUND AND OBJECTIVE: The management of metastatic disease has been greatly influenced by molecular-based tumor classification and associated therapeutic targets, leading to a significant improvement in survival in many cases. This improvement, in both progression free survival and overall survival, has led to an increased incidence of brain metastases (BM) in a population with systemically well controlled disease or patients with promising therapeutic options available. Within this review, we discuss the paradigm of treatment for 5 to 15 BM, and how the treatment has evolved away from short-term palliation towards providing long term intracranial control. METHODS: A review of literature pertaining to treatment of multiple BM was performed. We searched in PubMed to identify literature on treatment of multiple brain metastases. Only English literature published until February 1st, 2022 was reviewed. KEY CONTENT AND FINDINGS: The management of 5-15 BM include multi-modality treatment pathways that are tailored towards each individual's primary cancer and burden of disease. Surgical resection of a dominant metastasis is still reserved for large symptomatic lesions, and is combined with post-operative local disease control. Overall, there is a shift away from whole brain radiation therapy (WBRT) due to side effect profile towards stereotactic radiosurgery (SRS). However, advances in WBRT continue to be studied, as well as the use of immunotherapy, targetable mutations, and synergistic effects between SRS and targeted therapies. CONCLUSIONS: The use of SRS to treat 5 to 15 BM is an increasingly acceptable and well-regarded practice, along with a combinatorial approach taking into account systemic options during all treatment timepoints.

Innovations in the Diagnosis and Surgical Management of Low-Grade Gliomas.

Low-grade gliomas are a broad category of tumors that can manifest at different stages of life. As a group, their prognosis has historically been considered to be favorable, and surgery is a mainstay of treatment. Advances in the molecular characterization of individual lesions has led to newer classification systems, a better understanding of the biological behavior of different neoplasms, and the identification of previously unrecognized entities. New prospective genetic and molecular data will help delineate better treatment paradigms and will continue to change the taxonomy of central nervous system tumors in the coming years. Advances in the field of radiomics will help predict the molecular profile of a particular tumor through noninvasive testing. Similarly, more precise methods of intraoperative tumor tissue analysis will aid surgical planning. Improved surgical outcomes propelled by novel surgical techniques and intraoperative adjuncts and emerging forms of medical treatment in the field of immunotherapy have enriched the management of these lesions. We review the contemporary management and innovations in the treatment of low-grade gliomas.

Updated response assessment criteria for high-grade glioma: beyond the MacDonald criteria.

High-grade glioma continues to be a challenging disease with few effective treatment options and a poor prognosis, necessitating intensive research into alternate therapies. The Response Assessment in Neuro-Oncology (RANO) committee was formed to create a robust endpoint assessment criteria in Neuro-Oncology in order to streamline the assessment of new therapies in a uniform fashion. The aim of this committee is to create standardized guidelines to assess clinical and imaging response in the treatment of brain tumors, which can then be applied in clinical trials. Since the first RANO report was published in 2010, its criteria have been widely adopted and utilized in clinical trials worldwide. Standardized application of the RANO response assessment criteria in clinical trials will result in the generation of strong clinical data, which can subsequently be pooled and analyzed to attain a more accurate assessment of treatment efficacy. In this review, we summarize the current RANO guidelines in patients with high-grade glioma, highlighting the key clinical and imaging criteria used for RANO evaluation and introducing the role of newer imaging and biomarkers.