Brain tumours may be cancerous (malignant )or non cancerous (benign). Almost 1 million cases occur in a year in India. Exact Cause is usually not known. Brain tumour can arise primarily in brain called Primary brain tumour and secondarily can arise from other part of the body and spread to brain called secondaries or metastatic brain tumours.
1. Benign – slow growing, not cancerous and won’t spread to surrounding structures
2. Malignant – fast growing, cancerous and spread to surrounding structures. May reoccur after the treatment.
Most common brain tumours – Meningiomas, Gliomas, Pituitary adenomas, Acoustic schwannomas.
I) Primary brain tumours –
- Meningiomas – Arise from meninges
- Gliomas – Arise from brain and spinal cord.- astrocytomas, glioblastomas, ependymomas, oligoastrocytomas,and oligodendrogliomas.
- Pituitary adenomas
- Acoustic schwannomas
- Craniophyryngiomas-non cancerous
- Medulloblastomas- common in children and behind brain and spreads in cerebrospinal spinal fluid.
- PNET – Primitive neuroectodemal tumour, starts in embryonic cells of brain. These can occur anywhere in brain.
There are 4 grades
- Grade 1
- Grade 2
- Grade 3
- Grade 4
Lower the grade is least malignant(usually no contrast enhancement), grade 4 is highly malignant(contrast enhances).
II) Secondaries(metastatic) –
Secondary (metastatic) brain tumours are tumours that result from cancer that starts elsewhere in your body and then spreads (metastasizes) to brain. Secondary brain tumours most often occur in people who have a history of cancer. But in rare cases, a metastatic brain tumour may be the first sign of cancer that began elsewhere in your body.
In adults, secondary brain tumours are far more common than are primary brain tumuors.
Any cancer can spread to the brain, but common types include:
- Breast cancer
- Colon cancer
- Kidney cancer
- Lung cancer
- Gynecological tumours
Risk factors are
- Ionising radiation
- Epstein Barr virus
- History of cancer in the family
- Exposure to vinyl chloride
All headaches are not due to brain tumours, all tumours may not produce headaches.
- Headaches in the morning
- Extreem nausea
- Headache relieved by vomiting
- Vision problems
- Repeated episodes of headache
- Symptoms depending on location of tumour-behaviour disturbance, ataxia
Management – Brain tumours are diagnosed by
- CT Scan-screen the brain most of the time.
- MRI SCAN – to know the exact location and spread.
- MR Spectroscopy – to know the nature.
- PET scan – to know the secondaries.
- ANGIOGRAM – to see the brain vessels
- Biopsy from the tumour.
- Low grade astrocytoma is 5 years or more
- Glioblastoma – 1 year
- Anapalastic astrocytoma – 3 years
Lower grade can be converted into higher grade
- Surgery – Surgery is the usual first treatment for most brain tumours. Neuroradio-imaging, earlier diagnosis, systematic planning, preoperative, anaesthetic management, Neuro microscopes and surgical micro instruments, it is possible to remove significant amounts of brain tumour through relatively safely.For most benign tumours, treatment is often successful and a full recovery is possible, although there’s sometimes a small chance the tumour can reoccur. Regular follow-up is advised to monitor.
- The advent of PET CT, IGRT(image guided radiation therapy) and Gamma knife surgery(stereotactic radio surgery) is revolutionizing the treatment of various problems in the brain, including benign brain tumours in eloquent locations, like the motor cortex, basal ganglia, brain stem or near the optic nerve.Howsoever, all Brain tumours do not require operation and many are treatable with radiation or chemotherapy or Gamma Knife.
- Radio surgery
- Gamma knife
Advances in tumour surgery – which has made brain surgery safe
- CUSA(Cavitron ultrasonic surgical aspiration)
- Neuronavigation(minimally invasive)
- Awake craniotomy(to resect tumour accurately)
- Interventional MRI(real time surgery)
- Pre-operative embolisation(endovascular to minimise bleeding)
- Speech therapy
- Occupation therapy