Abstract. Meningioma is a common intracranial tumor involving the meninges. The localization of this type of tumor is rarely extracranial due to its typically low invasive properties. Furthermore, invasion of the middle ear is exceptional. The present study reported a case of meningioma extending into the middle ear from the middle cranial fossa through the tegmen tympani. The clinical and pathological characteristics, as well as the outcome of the patient, were described. IntroductionMeningioma is a common intracranial tumour, accounting for 13-19% of all primary brain tumors (1). This tumor is generally encapsulated and benign (2). The symptoms of meningioma depend on the pressure of the tumor on the brain or spinal cord and the intracranial location of the tumor (3). Symptoms, such as seizures, single or multiple muscle twitches, spasms, loss of control of body functions, change in sensation and partial or total loss of consciousness, are associated with the different locations of the mass (1,4). Meningiomas accounted for ~33.8% of all the primary brain and central nervous system tumors reported in the United States between 2002 and 2006 (2). Furthermore, in recent decades, increased exposure to risk factors has determined an increase in the incidence of primary brain tumors, inclusive of meningioma, in several countries (5). The predominant risk factor identified is the exposure to ionizing radiation; however, other risk factors may be associated with the risk of meningioma, including elevated estrogen and/or progesterone hormone levels (2,6,7), head trauma (2), cell phone use (2,8), breast cancer (2), occupation (2), diet (2). Notably, a significant inverse correlation has been identified between meningioma and allergies (2,9); Linos et al (10) revealed that individuals with a history of allergy exhibited a lower risk of developing brain tumours than individuals with no history of allergy. Meningiomas have a higher incidence rate among female individuals, with a female to male ratio of ~2:1 (5). In addition, age-specific incidence rates indicate that risk increases with age. Prevalence rates for non-Hispanic individuals of African descent are marginally higher (6.67 per 100,000 persons) compared with Caucasian non-Hispanic and Hispanic individuals (5.90 and 5.94 per 100,000 persons, respectively) (2,4). The primary treatment strategy for meningiomas is total resection surgery if the tumor is benign and in an area of the brain where it can be safely and completely removed. Subsequently, radiation therapy is applied for the most malignant cases of meningioma or when surgery is not feasible due to the meningioma location.Extracranial meningiomas are uncommon (accounting for <2% of meningiomas) (11), particularly those extending into the middle ear. The present study described a rare case of meningioma extending into the middle ear from the middle cranial fossa through the tegmen tympani. Written informed consent was obtained from the patient. Case reportIn May 2004, a 56-year-old woman presented to the Ear Nos...