Primary Extracranial Meningiomas of the Head and Neck

Meningiomas represent the most common benign histological tumor of the central nervous system. Usually, meningiomas are intracranial, showing a typical dural tail sign on brain MRI with Gadolinium, but occasionally they can infiltrate the skull or be sited extracranially. We present a systematic review of the literature on extracranial meningiomas of the head and neck, along with an emblematic case of primary extracranial meningioma (PEM), which provides further insights into PEM management. A literature search according to the PRISMA statement was conducted from 1979 to June 2021 using PubMed, Web of Science, Google Scholar, and Scopus databases, searching for relevant Mesh terms (primary extracranial meningioma) AND (head OR neck). Data for all patients were recorded when available, including age, sex, localization, histological grading, treatment, possible recurrence, and outcome. A total of 83 published studies were identified through PubMed, Google Scholar, and Scopus databases, together with additional references list searches from 1979 to date. A total of 49 papers were excluded, and 34 manuscripts were considered for this systematic review, including 213 patients. We also reported a case of a 45-year-old male with an extracranial neck psammomatous meningioma with sizes of 4 cm × 3 cm × 2 cm. Furthermore, whole-body 68Ga-DOTATOC PET/CT was performed, excluding tumor spread to other areas. Surgical resection of the tumor was accomplished, as well as skin flap reconstruction, obtaining radical removal and satisfying wound healing. PEMs could suggest an infiltrative and aggressive behavior, which has never found a histopathological correlation with a malignancy (low Ki-67, <5%). Whole-body 68Ga-DOTATOC PET/CT should be considered in the patient’s global assessment. Surgical removal is a resolutive treatment, and the examination of frozen sections can confirm the benignity of the lesion, reducing the extension of the removal of healthy tissue surrounding the tumor.

Skull Base Primary Extracranial Meningioma with Hyperostosis in a Small Mixed-Breed Dog

ABSTRACT A 7 yr old female spayed Chihuahua-terrier mix was presented for a progressive dry, hacking cough over 9 mo, with dyspnea aggravated by eating and drinking. Computed tomography of the skull revealed a large mineral attenuating mass associated with the left skull base, without intracranial involvement. A modified ventral paramedian hypophysectomy approach along the medial aspect of the left ramus was used to approach the base of the skull. Ninety percent of the mass was debulked via high-speed pneumatic burr. Histopathology was consistent with hyperostosis originating from a primary extracranial meningioma (ECM), with the tissue staining positive for vimentin and negative for cytokeratin. The patient was symptom free for 9 mo before clinical signs returned because of tumor recurrence and was euthanized 11 mo postoperation because of diminished quality of life. ECM is uncommonly reported in the dog, and to the authors’ knowledge has not previously been reported with hyperostosis or located along the skull base at the level of the tympanic bulla. Additionally, although hyperostosis predominantly occurs as diffuse bone thickening adjacent to a meningioma, proliferative focal hyperostosis is uncommon. Given the findings in this patient, ECM should be considered as a differential diagnosis for osseous skull base masses.

Extracranial Meningioma in the Scalp with Concurrent Steatocystoma

This report documents a rare case of an extracranial meningioma on the posterior scalp without apparent dural connection. Additionally, a sebaceous steatocystoma of the anterior scalp presented alongside the meningioma. A steatocystoma localized to the scalp is also remarkably rare. To our knowledge, this is the first report documenting both an extracranial meningioma and a steatocystoma presenting concurrently on the scalp. A male patient in his thirties presented with a mass lesion on the scalp. A CT scan revealed one posterior scalp mass with no intracranial abnormalities. Post excision histologic examination confirmed an extracranial meningioma (meningothelial variant, WHO Grade I). A second anterior scalp mass, not revealed by CT scan, was discovered during surgery. It was excised and diagnosed as a steatocystoma. Meningiomas predominantly occur intracranially but, in some instances, may present as a standalone extracranial tumor without intracranial abnormalities. Because extracranial meningioma is uncommon, it may be overlooked during clinical diagnosis of scalp masses. We recommend that this neoplasm be routinely considered in the differential diagnosis of extracranial tumors. The discovery of another rare tumor—a steatocystoma located in immediate proximity on the scalp—is further remarkable. We briefly review relevant case reports and etiologies and consider a potential relationship between the two neoplasms. However, it remains more likely that the concurrence of these tumors in our patient was simply coincidental.

Mandibular meningioma—a rare case report of a second extracranial meningioma and a systematic literature review

Meningiomas are benign tumours common in the central nervous system. Primary extracranial meningiomas in the jaws are extremely rare. We performed a systematic review of all the primary extracranial meningioma arising in the jawbones reported in the English-language literature including indexed and non-indexed journals and we report a unique case in our hospital of a man with two primary extracranial meningiomas, the first frontal intradiploic and 16 years later, a second located in the mandible. We found 14 cases with primary jaws meningioma and we report another one. A mandibular predominance was observed with only four cases in the maxilla. Most of them occurred in women, with a mean age of 35.9 years. It is the first published case of a patient with two primary extracranial meningiomas one of them in the mandible, which the gender, age and laterality of the lesion are less frequent.