Meningioma in Cats: Symptoms, Causes, Treatment & Life Expectancy

What Is Meningioma in Cats?

Meningioma is the most common primary brain tumor in cats, and the good news is that most feline meningiomas are benign, slow-growing, and often surgically curable. This tumor accounts for roughly 56–59% of all primary intracranial (inside the skull) neoplasms in cats ^{[1, 2, 3]}. It originates from arachnoid cap cells, which are specialized cells in the thin membranes (called the meninges) that wrap around the brain and spinal cord. The tumor grows as an extra-axial mass, meaning it sits outside the brain tissue itself but inside the tough outer covering called the dura mater ^{[2, 4]}.

Although meningiomas are technically benign (World Health Organization [WHO] Grade I), they cause serious problems by slowly squeezing the adjacent brain as they enlarge within the rigid skull. Over time, this compression leads to inflammation, swelling (peritumoral edema), increased pressure inside the skull (intracranial pressure), and, in severe cases, brain herniation ^{[1, 5, 3]}.

Feline meningiomas differ from their canine counterparts in several important ways. The vast majority are well-encapsulated and minimally invasive, which makes them more amenable to surgical removal than the same tumor in dogs ^{[1, 4, 3]}. Most occur in the forebrain (the front portion of the brain), with over 90% arising in the cerebral meninges ^{[5, 6, 7]}. Multiple meningiomas are not rare and have been reported in up to 17% of affected cats, often of different histological subtypes ^{[1, 4]}. Median age at diagnosis is 11–12 years, making this predominantly a disease of older (geriatric) cats, though the reported range spans 3 to 21 years ^{[1, 2, 3]}.

There is no clear sex predisposition, and domestic shorthair cats are most commonly affected, though this likely reflects their overall population frequency rather than a true breed risk. Some studies have suggested a higher risk in American Shorthair and Norwegian Forest Cat breeds ^{[2, 4, 7]}. Malignant (anaplastic) meningiomas are exceedingly rare in cats; nearly all are benign Grade I lesions ^{[5, 3, 8]}.

Symptoms and Red Flags of Meningioma in Cats

The clinical signs of meningioma in cats usually come on slowly and worsen progressively, which can make early detection tricky, but knowing what to watch for can save your cat's life. Because the tumor grows gradually, signs often reflect not only the mass itself but also secondary effects like brain swelling, increased intracranial pressure, and brain herniation ^{[3, 4]}.

The most common warning signs depend on where the tumor sits inside the skull:

• Forebrain (cerebral) meningiomas, the most common location (>90% of cases), typically cause:

• Altered mentation: your cat may become quieter, less interactive, or unusually withdrawn ^{[3, 4, 5, 1]}

• Compulsive behaviors such as circling, pacing, or pressing the head against a wall or furniture (a behavior known as "head pressing") ^{[3, 4, 5, 1]}

• Visual deficits, including bumping into objects or appearing blind ^{[3, 4, 1]}

• Seizures occur in about 14–25% of cats with meningioma, less frequently than in dogs, and can be focal (affecting one part of the body) or generalized (whole-body convulsions) ^{[3, 4, 1]}.

• Cerebellopontine angle or brainstem tumors (a less common location) typically cause:

• Loss of coordination (ataxia), abnormal paw placement (dysmetria), and intention tremors (shaking that worsens when reaching for something)

• Head tilt, involuntary eye movements (nystagmus), and cranial nerve deficits

• Circling may also be seen ^{[4, 1]}

• Spinal meningiomas typically cause local spinal pain (hyperesthesia), progressive weakness or paralysis of the limbs (paresis), and proprioceptive ataxia, meaning your cat may scuff its toes or knuckle over when walking. The exact deficits depend on which segment of the spinal cord is compressed.

In addition to neurological signs, many cats show non-specific symptoms. Weakness has been reported in up to 71% of cases. Altered consciousness, reduced appetite (dysorexia or anorexia), and weight loss are also common ^[1]. In severe cases, brain herniation (when brain tissue is pushed through one of the rigid openings in the skull) can lead to rapid deterioration, with stupor, coma, and death ^[9]. Some cats with meningioma may also have other concurrent non-neurological health conditions, such as chronic kidney disease and hyperthyroidism, which can complicate the overall clinical picture and potentially delay recognition of the tumor's specific signs ^[6]. Importantly, surgical intervention can yield excellent outcomes and should be considered even in older cats, regardless of how severe the initial signs appear ^[2].

Causes and Risk Factors for Feline Meningioma

The single biggest risk factor for meningioma in cats is age, nearly all cases occur in older cats, but the underlying cause in most individual cats remains unknown. Meningioma is overwhelmingly a disease of geriatric felines, with a median age at diagnosis of 11–12 years and over 95% of cases occurring in cats older than 7 years ^{[1, 2, 3]}.

Sex does not appear to play a significant role; males and females are affected in roughly equal numbers ^{[2, 7, 8]}. Breed predisposition remains controversial. Domestic shorthair and domestic longhair cats are most often affected, but this most likely reflects how common these breeds are in the general population rather than a true genetic predisposition. Some studies have reported a statistically higher risk in American Shorthair and Norwegian Forest Cat breeds, particularly in certain geographic regions ^{[4, 7]}.

A few specific, less common associations have been identified:

• Mucopolysaccharidosis type I, a rare inherited metabolic disorder, has been linked to meningioma development in young cats (under 3 years of age), but this accounts for very few cases ^[4].
• In humans, prior radiation therapy to the head is a well-established risk factor for meningioma, but this association has not been documented in cats and remains unconfirmed for this species.

For the vast majority of cats, meningiomas are considered sporadic, with no clear inherited or environmental trigger. No familial or genetic syndromes predisposing cats to meningioma have been identified.

Types and Classification of Meningioma in Cats

Understanding meningioma "types" matters because it influences both prognosis and treatment decisions, but the good news is that almost all feline meningiomas are the low-grade, benign kind. Veterinarians classify these tumors in two main ways: by anatomical location and by histological (tissue-based) grade.

By anatomical location, meningiomas are categorized as:

• Cerebral (forebrain) meningiomas, the most common form, accounting for over 90% of cases. These typically involve the supratentorial meninges (the membranes covering the upper portion of the brain) and the falx cerebri (a tough sheet of tissue that separates the two hemispheres of the brain) ^{[7, 6, 3]}.
• Cerebellopontine angle meningiomas, rare; located where the cerebellum meets the brainstem ^{[7, 6]}.
• Spinal meningiomas, uncommon (<5%); found in either the cervical (neck) or thoracolumbar (mid-to-lower back) spinal cord ^{[7, 6, 3]}.

About 14–17% of cats have multiple meningiomas at diagnosis, often of different histological subtypes ^{[1, 4]}. The WHO grading system, adapted for animals, divides meningiomas into three grades:

• Grade I (benign), the most common in cats
• Grade II (atypical), rare
• Grade III (anaplastic/malignant), exceedingly rare ^{[10, 6]}

Within Grade I, several subtypes exist:

• Meningothelial, sheets of polygonal cells
• Fibrous (fibroblastic), spindle cells arranged in bundles
• Transitional/mixed, a combination of patterns
• Psammomatous, contains calcified bodies ^{[2, 8, 4]}

Feline meningiomas have some distinctive features compared to other species. They are often fibrotic and tend to contain cholesterol clefts (slit-like spaces where cholesterol crystals once sat) and areas of linear or focal calcification, rather than the classic round psammoma bodies seen more often in humans ^{[4, 7, 6]}. They also rarely infiltrate (invade) brain parenchyma ^{[4, 7, 6]}. Grade II (atypical) and Grade III (anaplastic) meningiomas are exceedingly rare in cats, and their clinical behavior is not well characterized ^{[3, 8]}.

How Meningioma Is Diagnosed in Cats

Diagnosing meningioma in cats involves a combination of neurological examination and advanced imaging, MRI is the gold standard. A presumptive diagnosis is built from your cat's age, breed, the pattern and progression of neurological signs, and characteristic findings on MRI or CT ^{[3, 4]}.

The neurological examination localizes the lesion to one of three regions: the forebrain, the brainstem/cerebellum, or the spinal cord, which then guides imaging selection ^{[3, 4]}. Once localized, advanced imaging provides a much more detailed picture:

• MRI (magnetic resonance imaging) is the preferred diagnostic tool. Meningiomas typically appear as well-demarcated, extra-axial masses (sitting outside the brain tissue itself) with these characteristic features:

• On T1-weighted images (a standard MRI sequence): iso- to hypointense (similar in brightness or darker than surrounding brain)

• On T2-weighted images (another MRI sequence that highlights fluid and swelling): hyperintense (brighter than surrounding brain)

• Strong, uniform contrast enhancement after injection of a contrast agent

• A "dural tail" (a thin line of enhancement extending from the mass along the adjacent membrane), which is a classic clue

• MRI provides a correct presumptive diagnosis in approximately 95% of cases ^[3]

• CT (computed tomography) also reveals meningiomas, typically showing a hyperdense extra-axial mass (one that appears brighter than surrounding brain tissue on CT) with marked contrast enhancement, sometimes with visible mineralization. Calvarial hyperostosis (thickening of the skull bone overlying the tumor) may also be seen ^{[3, 4]}.

Imaging alone cannot reliably distinguish tumor subtype or grade; definitive diagnosis before death requires histopathological examination (microscopic analysis of tissue) of a sample obtained at surgery or biopsy ^[3]. What this means for your cat: Your veterinary team will likely have a strong suspicion of meningioma based on MRI alone, but the final "label" on the tumor requires a tissue sample.

Additional tests can support the diagnosis:

• CSF (cerebrospinal fluid) analysis is neither sensitive nor specific for meningioma. The total nucleated cell count is usually normal, and albuminocytologic dissociation (elevated protein with a normal cell count) occurs in only about 30% of cases. CSF analysis is most useful for ruling out infectious or inflammatory conditions like meningitis ^[3].
• Immunohistochemistry (a laboratory technique that uses antibodies to identify specific proteins in tissue) can confirm meningioma. E-cadherin (a cell-adhesion protein) is expressed in over 92% of feline meningiomas, along with variable expression of vimentin, cytokeratin, and β-catenin ^[7].
• Stereotactic brain biopsy (a minimally invasive needle biopsy guided by imaging) is rarely needed, as most diagnoses are confirmed after surgical removal or at necropsy (post-mortem examination).

Treatment Options for Meningioma in Cats

Meningioma in cats is often a treatable condition, and surgery offers the best chance for long-term control or even cure. The treatment plan depends on the tumor's location, size, your cat's overall health, and your family's financial and personal considerations.

Surgical excision is the treatment of choice for accessible meningiomas ^{[6, 5, 3, 1]}. Because feline meningiomas are typically well-encapsulated and minimally invasive, complete gross resection (removal of all visible tumor) is often achievable. Subtotal resection (removing most, but not all, of the tumor) is performed when the tumor is too close to vital structures to allow complete removal ^{[3, 8]}. Common surgical approaches include the rostrotentorial craniotomy/craniectomy (opening a window in the skull at the front of the head), which provides access to most forebrain tumors ^[3]. Cranioplasty (reconstruction of the skull defect) using a PMMA (polymethyl methacrylate, a medical-grade bone cement) prosthesis may reduce overall postoperative complications ^{[8, 2]}.

Risks of surgery include:

• Perioperative mortality (death during or shortly after surgery): 6% to 17% in various studies ^{[3, 2, 8]}
• Major complications: hemorrhage, increased intracranial pressure, seizures, anemia, and brain herniation through the surgical opening ^{[3, 2, 8]}
• Postoperative seizures are the most frequent complication, especially in male cats ^{[8, 2]}

Radiation therapy is an effective alternative for tumors that cannot be surgically removed or as adjuvant (follow-up) therapy in select cases. Approaches include hypofractionated radiation (a few large doses), stereotactic radiosurgery (highly focused, precise radiation), or fractionated radiation (many smaller doses over time). Median survival times of 339–515 days are reported with radiation alone ^{[5, 8, 2]}.

Adjuvant radiation after complete resection of a Grade I meningioma is not routinely recommended because no clear survival advantage over surgery alone has been demonstrated ^[4]. It may be reserved for higher-grade tumors, incomplete resections, or recurrence.

Medical (palliative) management focuses on reducing secondary effects and controlling symptoms rather than curing the tumor:

• Corticosteroids (anti-inflammatory medications like prednisolone) can temporarily reduce peritumoral edema (swelling around the tumor) and improve your cat's comfort ^{[3, 8, 2]}
• Antiepileptic drugs (seizure-control medications) such as phenobarbital or levetiracetam help control seizures ^{[3, 8, 2]}

However, the median survival with palliative medication alone is only about 18 days ^{[3, 8, 2]}, a stark contrast to surgical outcomes.

For local recurrence, repeat surgery and/or salvage radiotherapy can be successful in achieving further disease control ^[3]. No chemotherapy protocol has an established role in the routine management of feline meningioma. Hydroxyurea has shown in-vitro evidence of slowing meningioma cell multiplication; however, clinical use in cats carries well-documented risks of dose-dependent myelosuppression (anemia, thrombocytopenia, neutropenia), GI effects, and rare cutaneous/digital side effects, and requires regular CBC monitoring. Further clinical investigation specifically evaluating efficacy and safety in cats is needed ^[3].

Cost of Treating Meningioma in Cats

Costs for diagnosing and treating feline meningioma can be substantial, but understanding the range helps you plan and explore financing options. Prices vary widely based on geographic location, the specific referral center, and the complexity of your cat's case.

• Pre-treatment diagnostics, including neurological examination, MRI or CT scan, bloodwork, and urinalysis, typically range from $1,500 to $3,500 in North America. In the UK, similar workups often cost £1,200–£2,800, while costs in continental Europe and Australia vary by country and clinic.

• Craniotomy with tumor resection, covering surgery, hospitalization, intensive care, and medications, generally runs between $4,000 and $10,000 or more in the US. Comparable procedures in the UK may cost £3,500–£8,000.

• Radiation therapy (stereotactic or fractionated) typically costs $5,000 to $12,000 in North America and often involves multiple anesthetic episodes plus potential travel to a specialty center.

• Ongoing medical management, antiepileptic drugs, corticosteroids, and follow-up visits, usually adds $50 to $150 per month in the US, depending on the medications and frequency of rechecks.

• Pet insurance plans that include neurological coverage may reimburse a significant portion of these costs. Many owners also use third-party financing options (such as CareCredit in the US) or charitable organizations to help with expenses.

A detailed financial discussion with the specialist and your primary veterinarian before committing to treatment is essential. Costs vary widely, and your team can help you explore all available options.

Prognosis and Life Expectancy With Meningioma

The prognosis for cats with meningioma, particularly after surgical excision, is genuinely encouraging, with many cats living years beyond diagnosis. With surgery, reported median survival times range from 22 to 37 months across multiple studies, and one recent case series reported a median survival of 1,674 days (over 4.5 years) for cats that survived the immediate postoperative period ^{[8, 2, 5]}.

One- to three-year survival rates after surgery are approximately 82%, and many cats ultimately die of unrelated geriatric conditions (kidney disease, heart disease, etc.) rather than tumor progression ^{[2, 1]}. This is one of the most important positive takeaways: surgery offers cats a real chance at many additional years of good-quality life.

Recurrence after surgery is reported in 11% to 39% of cats, occurring anywhere from 3 to 60 months postoperatively ^[1]. Tumor location influences outcome: forebrain meningiomas carry the best prognosis, while tumors in the caudal fossa (back of the skull, involving the brainstem and cerebellum) carry a poorer prognosis due to surgical difficulty and higher perioperative risk ^[3]. Multiple meningiomas do not necessarily shorten survival if they can be resected or are clinically silent ^[1].

High-grade meningiomas (Grade II and III) are rare in cats; in one study, only five Grade II and one Grade III tumors were identified among 45 cases, and reliable prognostic data for higher-grade tumors are lacking ^{[8, 7]}. Importantly, age at surgery does not influence survival time or complication rate, older cats do just as well as younger ones ^{[1, 8]}.

For non-surgical treatment, radiation therapy yields a median survival of 339–515 days, while medical palliation alone results in a median survival of just 18 days ^{[8, 2]}.

What Happens If a Cat's Meningioma Is Left Untreated?

Without treatment, meningiomas continue to grow slowly but inexorably, leading to progressive neurological decline and, ultimately, life-threatening complications. As the tumor enlarges, it compresses more brain tissue and increases intracranial pressure ^[4].

Clinical signs advance from subtle lethargy and behavior changes to profound stupor, coma, intractable seizures, and life-threatening brain herniation ^{[3, 9]}. Brain herniation, when brain tissue is forced through one of the rigid openings in the skull, can take three forms:

• Cingulate herniation (the frontal lobe is pushed under the falx cerebri)
• Transtentorial herniation (the brain is pushed through the tentorial notch, a small opening in the membrane that separates the cerebrum from the cerebellum)
• Foramen magnum herniation (the cerebellum and brainstem are pushed downward through the base of the skull)

Each of these can cause rapid deterioration with stupor, coma, and death ^{[3, 9]}. What this means for your cat: The median survival with only palliative medications is approximately 18 days once neurologic deficits become apparent, reflecting just how rapidly the situation can deteriorate ^{[8, 2]}.

Euthanasia is often the kindest choice when a cat's quality of life declines due to uncontrolled pain, seizures, inability to eat, or loss of mobility. Brain herniation is frequently the terminal event leading to cardiorespiratory arrest ^[9].

Living With and Managing Meningioma Long-Term

Most cats who survive meningioma surgery recover well and enjoy high quality of life, many owners report their cats return to essentially normal function. In one survey, 12 of 14 owners were satisfied with the outcome, and 13 of 14 would choose surgery again ^{[8, 1]}. Eleven of 14 owners found postoperative home care easy or acceptable, and 12 of 14 described their cats as completely normal one month after surgery ^{[8, 1]}.

Long-term management involves:

• Periodic monitoring, neurological examinations every 3–6 months and repeat MRI if new or recurrent signs develop, since tumor regrowth can occur months to years after surgery ^[2].
• Seizure management, if seizures persist postoperatively, antiepileptic therapy with phenobarbital or levetiracetam is continued, with dosage adjustments based on seizure control and serum drug levels ^[3].
• Corticosteroid tapering, when prednisolone is used, the dose should be gradually reduced to the lowest effective dose to minimize side effects ^[3].
• Geriatric comorbidity management, chronic kidney disease, cardiac disease, and hyperthyroidism are common in older long-term survivors and require ongoing care ^[1].

Palliative management when surgery isn't an option includes prednisolone (tapered to the lowest effective dose) and antiepileptic therapy for seizure control ^{[6, 3]}. Quality of life remains high in long-term survivors, and many owners would choose the same treatment path again ^{[8, 1]}.

Quality of Life and End-of-Life Decisions for Cats With Meningioma

Monitoring your cat's quality of life is one of the most loving things you can do, and there are structured tools to help you. A validated quality-of-life assessment tool such as the HHHHHMM scale (Hurt, Hunger, Hydration, Hygiene, Happiness, Mobility, More good days than bad) helps owners and veterinarians make more objective decisions about a cat's well-being.

Red flags for declining quality of life include:

• Persistent anorexia and weight loss
• Inability to walk unassisted
• Uncontrolled pain or seizures
• Loss of interest in surroundings
• Incontinence ^[6]

Euthanasia should be considered when medical interventions no longer relieve suffering, when your cat experiences more bad days than good, or when severe neurological deficits preclude a dignified quality of life. End-of-life care for cats with meningioma may include pain management, anti-nausea medications (antiemetics), appetite stimulants, and environmental modifications to ensure comfort. Many owners opt for hospice care or in-home euthanasia to reduce stress for their cat.

Veterinarians should provide emotional support, clear communication, and guidance about the anticipated progression of untreated meningioma to help families make compassionate end-of-life decisions.

Similar Conditions That Can Look Like Meningioma

Several other conditions can mimic meningioma in cats, which is why advanced imaging and sometimes additional testing are essential. Distinguishing these "look-alike" conditions matters because the treatments, and prognoses, can be very different.

Other primary brain tumors:

• Gliomas (astrocytoma, oligodendroglioma) are usually intra-axial (arising from within the brain tissue itself) and less well-demarcated on MRI ^{[3, 4]}.
• Choroid plexus tumors arise from the tissue that produces cerebrospinal fluid (CSF), sit within the brain's ventricles (fluid-filled cavities), and may cause hydrocephalus (buildup of fluid in the brain) ^{[3, 4]}.

Secondary intracranial neoplasia (cancers that have spread to the brain from elsewhere in the body):

• Lymphoma is the most common non-primary brain tumor in cats and often presents with multifocal central nervous system signs ^[3].
• Pituitary macroadenomas (large, benign tumors of the pituitary gland) occupy the sellar region (the bony socket at the base of the skull that houses the pituitary gland) and cause endocrine disturbances ^[3].

Inflammatory conditions:

• Granulomatous meningoencephalomyelitis (an inflammatory disease of the brain and its membranes) or feline infectious peritonitis (FIP) can mimic meningioma on CT and MRI as a contrast-enhancing mass with mass effect, but CSF analysis (showing elevated white cells [pleocytosis] and elevated protein) and specific pathogen testing help differentiate these ^[4].

Vascular events:

• Ischemic or hemorrhagic stroke (sudden loss of blood flow or bleeding in the brain) typically has a peracute (very sudden) onset and lacks the slowly progressive course of meningioma; MRI with diffusion-weighted imaging (a specialized sequence that detects acute stroke) shows no contrast-enhancing mass.

Metabolic or toxic encephalopathies (generalized brain dysfunction caused by a systemic problem):

• Conditions such as hepatic encephalopathy (brain dysfunction due to liver failure) or hypoglycemia (dangerously low blood sugar) cause diffuse, symmetrical neurological signs without a focal mass on imaging and are diagnosed via biochemical blood testing.

What We Still Don't Know: Gaps and Current Research

Despite being the most common feline brain tumor, meningioma still holds many unanswered questions, and active research aims to fill those gaps. Several important areas remain underexplored:

• Molecular pathogenesis: The genetic drivers of feline meningioma are largely unknown. Mutations commonly found in human meningiomas (such as NF2, AKT1, TRAF7, and SMO) have not been systematically evaluated in cats ^[6].
• Tumor stem-like cells and chemokine pathways: These emerging drivers of malignancy in human meningioma have not been studied in cats ^[6].
• Adjuvant radiotherapy benefit: Whether radiation therapy after complete excision of a Grade I meningioma meaningfully improves survival remains unclear; prospective randomized veterinary trials are needed ^[4].
• High-grade tumors in cats: Atypical and anaplastic meningiomas are so rare in cats that their true incidence, biological behavior, and optimal management remain unknown ^{[3, 8]}.
• Comparative One Health studies: Aligning feline meningioma with human molecular subtypes could accelerate the development of targeted therapies benefiting both species ^[6].
• Non-invasive biomarkers: No association has been found between standard bloodwork or urinalysis and intracranial meningioma in cats, and MRI features cannot predict tumor subtype or grade. Reliable non-invasive biomarkers for diagnosis, grading, and monitoring are still lacking ^[3].

Hydroxyurea has shown in-vitro evidence of slowing feline meningioma cell multiplication, and immunotherapeutic strategies have been explored in preliminary studies, but the role of tyrosine kinase inhibitors (a class of targeted cancer drugs that block specific enzymes involved in tumor growth) has not yet been investigated in feline meningioma ^{[6, 3]}.

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