Meningioma

Meningiomas are leptomeningeal neoplasms thought to originate from arachnoid membranes that form the cranial and spinal meninges ¹⁾.

Written with Louise Eisenhardt and published in 1938, Meningiomas is a monograph of incredible description and detail. The meticulous categorization of meningiomas, their presentation, clinical outcome, and surgical therapies are even further supplemented by Cushing's personal commentary, questions, and recollections. Cushing's genius was evident in his ability not only to make insightful clinical observations, but also to synthesize these ideas within the neurosurgical context of his era. As he says in Meningiomas, “Thus the pathological curiosity of one day becomes in its proper time a commonplace… most of which are one and the same disorder–had, for their interpretation, to await the advent of the Neurosurgeon ²⁾.

Meningioma epidemiology.

see Meningioma classification.

see Meningioma cell lines.

Meningioma immune response

see Meningioma etiology.

Meningioma genomics

see Meningioma Pathogenesis.

Pathologically, meningiomas are characterized by the following features:

Histological Subtypes: Meningiomas can be classified into various histological subtypes based on their appearance under a microscope. The World Health Organization (WHO) classifies meningiomas into different grades, including Grade I (benign), Grade II (atypical), and Grade III (malignant).

Cellular Composition: Meningiomas are composed of abnormal, proliferating meningothelial cells that originate from the arachnoid cap cells. These cells form whorls or sheets and may have variable cellularity.

Tumor Features: Meningiomas often have a well-defined border or encapsulated appearance, which allows for easier surgical removal. The tumor cells may exhibit different growth patterns, such as syncytial, fibroblastic, transitional, or psammomatous (calcification).

Mitotic Activity: The presence of mitotic activity, or dividing tumor cells, can be indicative of a higher-grade meningioma. A higher mitotic index is associated with increased cell proliferation and potentially more aggressive tumor behavior.

Brain Invasion: In some cases, meningiomas may invade the surrounding brain tissue, making complete surgical resection more challenging. The invasion of tumor cells into the brain parenchyma is associated with a higher likelihood of tumor recurrence.

Molecular genetics: Recent studies have identified specific genetic and molecular alterations in meningiomas, including mutations in the NF2 gene, which is involved in regulating cell growth and division. Other genetic changes, such as mutations in the TRAF7 and KLF4 genes, have also been associated with different meningioma subtypes.

Meningioma clinical features.

see Asymptomatic meningioma.

see Meningioma Diagnosis.

see Meningioma differential diagnosis.

see Meningioma treatment.

see Meningioma outcome.

see Meningioma metastases.

see Meningioma recurrence.

see Simpson grading system.

Meningioma Systematic reviews.

In November 2016, Almutairi et al. performed a title-specific search of the Scopus database using “Meningioma” as the search query term without publication date restrictions. The top 100 most cited articles were obtained and reviewed.

The top 100 most cited articles received a mean 198 citations per paper. Publication dates ranged from 1953 to 2013; most articles were published between 1994 and 2003, with 50 articles published during that period. NEUROSURGERY published the greatest number of top cited articles (22 of 100). The most frequent study categories were laboratorial studies (31 of 100) and natural history studies (28 of 100). Non-operative management studies were twice as common as operative management studies in the top cited articles. Neurosurgery as a specialty contributed to 50% of the top 100 list. The most contributing institute was the Mayo Clinic (11%); the majority of the top cited articles originated in the United States (53%).

They identified the top 100 most-cited articles on meningioma that may be considered significant and impactful works, as well as the most noteworthy. Additionally, they recognized the historical development and advances in meningioma research, and the important contributions of various authors, specialty fields, and countries. A large proportion of the most cited articles were written by authors other than neurosurgeons, and many of these articles were published in non-neurosurgery journals ³⁾.

Meningioma case series.