Overview of Brain Tumours

Brain cancers, in simple terms, refer to the uncontrolled growth of cancerous cells in the central nervous system (CNS), which includes the brain, spinal cord, and the protective layers surrounding them (meninges). These cancers are generally classified into two types: Primary and Secondary. Primary brain cancers originate within the CNS, while secondary brain cancers spread to the CNS from cancers that develop elsewhere in the body.

Primary brain cancers are categorized based on the type of cells from which they arise. Let’s discuss some of the key types:

• Glioblastoma: This cancer originates from glial cells, which provide nutrition and support to brain cells. Glioblastomas are highly aggressive tumors that can develop in the brain or spinal cord. These tumors often spread quickly, forming finger-like projections that invade and destroy surrounding healthy tissue. Common symptoms include severe headaches, seizures, weakness, vomiting, double vision, and memory problems.
• Meningioma: Meningiomas arise from the meninges, the membranes that surround and protect the brain and spinal cord. Most meningiomas are benign (non-cancerous), and only rarely do they become malignant (cancerous). Fortunately, they tend to grow very slowly, which means they often go undetected for years, with symptoms like headaches and cognitive impairments.
• Ependymoma: Ependymomas develop from ependymal cells, which produce cerebrospinal fluid that protects the brain and spinal cord. Symptoms of ependymomas include headaches, nausea, vomiting, and dizziness. Ependymomas in the spine may cause back pain, numbness, and problems with sexual function, urination, or bowel movements.
• Germ Cell Tumors: These rare tumors make up 2–3% of all primary brain cancers and usually develop in the pineal or suprasellar regions of the brain. They can spread to other parts of the brain, spine, and cerebrospinal fluid. Germ cell tumors are further divided into germinomas and non-germinomatous germ cell tumors. Non-germinomatous germ cell tumors (NS GCTs) are more common in Asian populations and are found more frequently in males, especially in the pineal region.
• Medulloblastoma: This tumor develops in the cerebellum and is the most common malignant brain tumor in children. Symptoms include morning headaches, double vision, difficulty standing, loss of appetite, and changes in behavior.
• CNS Lymphoma: These tumors arise from lymphatic tissue in the brain. Primary CNS lymphoma originates in the CNS, while secondary lymphoma spreads from elsewhere in the body. Symptoms often include confusion, weakness, difficulty speaking, headaches, and memory loss.
• Schwannoma: Schwannomas develop from Schwann cells, which surround and insulate cranial nerves. These tumors are slow-growing and may cause symptoms such as hearing loss, balance issues, weakness, sensory loss, and bowel or bladder problems.

In general, brain cancers are most commonly detected using magnetic resonance imaging (MRI). In some cases, a brain biopsy may be necessary to determine the specific type of tumor. Additional tests may be used to assess familial risk.

Treatment options for brain cancers include:

• Brain surgery: Surgical removal of the tumor.
• Gamma Knife surgery: A painless, computer-guided form of radiation therapy that delivers highly focused beams of energy to the tumor or lesion in the brain and upper spine.
• Radiation therapy: High doses of X-rays are used to either kill tumor cells or shrink the tumor.
• Chemotherapy: Anticancer drugs are used to destroy cancer cells in the brain and other parts of the body.
• Targeted therapy: Medications that target specific characteristics of cancer cells, minimizing damage to healthy cells.

Each of these treatments is tailored to the specific type and stage of the cancer, and may be used in combination for the best outcome.