A brain tumor is a puzzling oddity. Cells multiply uncontrollably, forming aberrant clusters or protuberances. These cancers may arise from cerebral tissue as primary agents or infiltrate the brain from other organs as metastatic or secondary malignancies. Depending on their size, positioning, and composition, these intrusive masses disturb brain functioning, causing severe injury. These mysterious growths may be benign, non-cancerous, or malignant, encroaching on nearby tissues and spreading their malevolence throughout the cerebral expanse or beyond. These cerebral interlopers can harm the afflicted physical and mental health. Therefore early discovery, intervention, and management are crucial.
2. Types of Brain Cancer
The central nervous system (CNS) encompasses the brain and spinal cord. The brain harbors primary tumors, which manifest in diverse subtypes:
- Glioma: A prevalent kind of brain tumor, gliomas exhibit multiple grades based on distinct characteristics. The nature and grade of your tumor determine the appropriate treatment, as not all gliomas are malignant.
- Meningioma: Originating from the meninges—membranes encasing the brain and spinal cord—meningiomas generally tend to be benign.
- Acoustic neuroma: A benign brain tumor emerging on the vestibulocochlear nerve impacts hearing and balance. Acoustic neuromas are infrequent and tend to grow slowly.
- Pineal tumor: These tumors arise in the deep-seated pineal gland within the brain and can be either malignant or benign.
- Pituitary tumor: Emerging from the pituitary gland, which regulates hormones, pituitary tumors necessitate collaborative treatment involving endocrinologists and ophthalmologists at MedStar Health. Certain tumors may also respond to medical intervention.
Brain tumors of secondary or metastatic origin disseminate to the brain from other body parts. Common cancers that metastasize to the brain originate in the lungs, breasts, skin, colon, and kidneys.
Brain Cancer Symptoms
The brain, being a complex organ, exhibits varied manifestations of symptoms due to the localization of tumors. Take, for instance, a tumor nestled in the cerebellum, situated at the posterior of the skull. In such cases, afflictions relating to movement, ambulation, equilibrium, and synchronization may arise. Moreover, alterations in vision may manifest if the tumor encroaches upon the optic pathway, the conduit for visual perception.
Furthermore, the dimensions and rapid growth of the tumor contribute significantly to the repertoire of symptoms encountered by an individual.
Prevalent indications of a brain tumor may encompass the following:
- Difficulty walking or dizziness/vertigo
- Muscle weakness (for example, arm and leg weakness)
- Headaches (persistent or severe)
Other common symptoms that can occur include:
- blurry vision,
- a change in a person’s alertness,
- mental capacity reduction or confusion,
- memory problems,
- personality changes,
- weakness on one side of the body,
- coordination problems,
- fatigue, and
- Personality shifts, hallucinations, a weakened side of the body, coordination issues, exhaustion, pins and needles sensations, or a diminished sense of touch can all be signs of a stroke.
These symptoms do not necessarily indicate brain cancer; no single symptom or combination can accurately predict its presence. Cancer can manifest in various brain regions, such as the occipital, frontal, parietal, temporal lobes, brainstem, or meningeal membranes (meninges for short).
While primary cerebral lymphoma and craniopharyngiomas originating from the pituitary gland can occur, they are rare. Additionally, certain brain cancers, such as meningeal and pituitary gland tumors, may exhibit minimal or no symptoms.
Brain Cancer Causes and Risk Factors
- Age – Brain tumors can occur in individuals of any age but tend to manifest more frequently in children and older adults.
- Gender – The occurrence of brain tumors is generally more prevalent in men compared to women. However, certain specific brain tumor types, like meningioma, have a higher incidence among women.
- Home and work exposures – Exposure to solvents, pesticides, oil products, rubber, or vinyl chloride might elevate the likelihood of developing a brain tumor.
- Family history – Approximately 5% of brain tumors may be attributed to hereditary genetic factors or conditions.
- Exposure to infections, viruses, and allergens – Contracting the Epstein-Barr virus (EBV) heightens the risk of CNS lymphoma. Notably, research indicates that patients with allergies or skin conditions exhibit a “lower risk” of glioma.
- Electromagnetic fields – Most studies examining the impact of electromagnetic fields, such as those emitted by power lines or cell phone usage, reveal no discernible association with an increased risk of brain tumor development in adults. However, some studies on animal models indicate an amplified risk. Due to contradictory information concerning risk in children, the World Health Organization (WHO) advocates for limiting cell phone usage and endorsing hands-free headsets for adults and children.
- Race and ethnicity – Gliomas are more prevalent in white individuals, while meningiomas are less likely to occur in this population compared to Black individuals.
Ionizing radiation – Prior exposure of the brain or head to ionizing radiation, including x-rays, constitutes a risk factor for brain tumors.
5. Brain Cancer Diagnosis
When faced with symptoms suggestive of a brain tumor, the doctor will meticulously assess your physical condition while inquiring about diverse aspects such as your well-being, daily routine, and familial background.
Various examinations may be employed to discern the presence and extent of a brain tumor, simultaneously gauging treatment effectiveness.
Imaging tests, which may include:
- CT (computed tomography) scans
- MRI (magnetic resonance imaging)
- Biopsy: Imaging studies may reveal a brain tumor-like location. A primary brain tumor diagnosis requires a tissue sample. Biopsies remove the sample. This method comprises needle-snipping a little tissue sample or physically removing the tumor. Your neurosurgeon will choose the best biopsy method for your tumor.
- Lumbar puncture: A needle withdraws a minute amount of cerebrospinal fluid, a clear liquid surrounding the brain and spinal cord, for microscopic examination. This test is done if doctors suspect a tumor has infiltrated the brain’s meninges and contaminated the spinal fluid.
- Molecular testing: Some primary brain cancers, such as gliomas, have unique molecular features due to mutational aberrations in tumor cells. These unique traits can diagnose a malignancy, improving medical prognosis and treatment.
Key mutations include:
- IDH mutation: Grades II and III gliomas receive IDH mutation testing. IDH-mutated cancers have better prognosis. Wildtype gliomas lack the IDH mutation.
- 1p/19q co-deletion: Oligodendroglioma diagnosis requires 1p/19q co-deletion. Chromosome segments 1 and 19 are lost. The 1p/19q co-deletion affects a large DNA region, unlike the single-gene IDH mutation. This mutation increases tumor chemotherapeutic susceptibility.
MGMT promoter methylation: Many brain tumor trials require MGMT mutation testing. MGMT increases cancer cell treatment resistance. MGMT tumor methylation improves prognosis and treatment responsiveness.
Brain Cancer stages
Brain tumors have several unexpected behaviors. Some start peacefully but become formidable foes and high-grade cancers. Some tumors start high-grade without a low-grade stage.
Brain tumor grades encompass distinct stages:
- Grade 1 (low-grade): Cells of grade 1 tumors bear an uncanny resemblance to their healthy counterparts, and their divergence is minimal. These sluggish neoplasms often accompany prolonged survival.
- Grade 2: Differently from normalcy, grade 2 tumor cells exude a marginally distinct appearance. While still classified as low-grade, grade 2 tumors manifest heightened aggression compared to their grade 1 counterparts. They harbor latent potential for escalation, sprouting into higher-grade tumors.
- Grade 3: Anomalous in form, grade 3 tumor cells engage in vigorous proliferation. Outpacing their grade 2 counterparts, grade 3 tumors exhibit accelerated growth, harboring the potential for evolution into grade 4 tumors.
Grade 4 (high-grade): The pinnacle of malignancy, grade 4 tumors brandish unrecognizable cells, relentlessly multiplying and expanding. Within the tumor, regions of necrotic cells may manifest, further compounding their belligerence.
Genetic conditions of Brain Cancer
It is very rare for brain tumors to run in families. A few inherited genetic conditions are linked to a higher risk of certain types of brain tumors.
- neurofibromatosis type 1 and type 2 (NF1 and NF2)
- tuberous sclerosis
- Li-Fraumeni syndrome
- von Hippel-Lindau syndrome
- Turcot’s syndrome
- Gorlin syndrome
- Cowden’s disease.
If your family is affected by one of these conditions, your GP can explain whether you have a risk of developing a brain tumor.
Brain Tumor Prevention Prognosis
A diagnosis of brain cancer can be life-altering. Numerous variables will determine the success of your outcome; some of them are:
- Size, grade, location of the tumor, and the type of brain tumor.
- Your age and general health How far the tumor has gone, both in the brain and elsewhere in the body
- How long you suffered from symptoms before a brain tumor was suspected
- How much the tumor in your brain hinders your everyday activities
- How you would like to be treated
- Your treatment team’s level of experience
The relative five-year survival rate for all brain tumor kinds (malignant and benign) is 75%, albeit this varies widely by age and tumor type. The overall survival rate for patients with only malignant tumors is only 36%.