By Dr Kunjal Lila
Brain in a complex vital organ of human body comprising of several parts that govern different functions of the body. Unfortunately, like all other organs, it is vulnerable to tumours that arise from uncontrollable growth of brain cells called glial cells as well as other structures like meninges, ependymal cells, pituitary and pineal glands, etc. The tumours may be non-cancerous or benign and cancerous or malignant. Brain is also a common site for metastasis from other cancers arising from other organs. Though the cause of primary brain tumours is not clear, risk factors like exposure to radiation and family history have been cited.
Signs and symptoms:
The signs and symptoms of a brain tumour depend on the location, size and rate at which it grows. As skull is a closed box in which brain resides, any growth within leads to increased intracranial pressure thereby leading to general symptoms like severe and persistent headaches, unexplained nausea and vomiting, blurring of vision, lack of energy, giddiness etc. If any of these general symptoms are persistent, it is time to see the doctor for a thorough evaluation. More specific symptoms related to the part of the brain involved by tumour are seen like seizures, loss of balance, difficulties in speech and hearing, loss of motor and sensory functions, hormonal imbalance, etc.
The diagnosis of brain tumours involves the triad of neurological examination, imaging studies and tissue diagnosis. A thorough neurological examination conducted by a specialist is essential and includes checking your vision, hearing, balance, coordination, strength, and reflexes, etc. This may help in identifying the part of the brain that is involved by tumour.
Imaging modalities include Magnetic resonance imaging (MRI), computerized tomography (CT) and positron emission tomography (PET). Of these, MRI is the modality of choice. Various specialised MRI scans including functional MRI, perfusion MRI and magnetic resonance spectroscopy may further help refine diagnosis. Last but not the least is the tissue diagnosis which goes hand in hand with imaging studies. As the brain is a complex organ with vital structures and the space is limited for the neurosurgeon to manoeuvre, the tumour may be excised completely, or a stereotactic needle biopsy may be carried out depending on the site and size of tumour. Many a times, the histopathologist is asked for an intra-operative consult also called as frozen section to confirm tumour in the biopsy excised as well as to distinguish malignant from benign lesions, which helps the neurosurgeon to take further operative decisions as the patient is still on the operation table. Apart from this, all tissues are subjected to routine histology, immunohistochemistry, and molecular testing.
A comprehensive report of the tissue includes the type of tumour like Astrocytoma, Oligodendroglioma, Glioblastoma, Ependymoma etc along with its grade which is divided into I to IV as per World Health Organisation (WHO). Grade I tumours are low grade tumours with better prognosis while the Grade IV tumours are high grade tumours with poorer prognosis. Unlike tumours of the other organs, molecular studies are an integral part of brain tumours. In fact, the latest WHO classification is an integrated histology-molecular classification. The common molecular tests include 1p19q co-deletion studies, IDH1/2 mutations, MGMT, TERT etc.
Based on the integrated clinico-radio-pathologic diagnosis of the brain tumour, a treatment plan is curetted. The treatment modalities include surgery, radiation, chemotherapy, targeted drug therapy etc. If the tumour is amenable to excision without damage to other structures, the neurosurgeon tries to excise as much tumour as possible as even part removal leads to decrease in symptoms. This is supplemented by another modality to treat the residual tumour. In cases where excision is not possible, a biopsy is done and depending on the tissue diagnosis, other modalities are offered to the patient. In case of metastasis, the site of primary tumour governs the further treatment. Post treatment rehabilitation therapy is also an integral part of treatment as brain tumours frequently affect motor skills, eyesight, vision, behaviour, thinking etc.
It has been quoted that “A person’s likelihood of developing brain tumour in their lifetime is less than 1%”. However, owing to the crucial role that the brain plays in our body, this low percentage is also significant. A vigilant patient, early consult with the specialist and multidisciplinary approach are a key to battle brain tumours.
(The author is the Doctor in charge & Consultant – Histopathology, Metropolis Healthcare Ltd. Views expressed are personal and do not reflect the official position or policy of FinancialExpress.com.)