A staging system is used for most types of tumors to help in the treatment planning and describe the characteristics of the tumor. It is based on factors such as – where the tumor is located, how far has it spread, and whether it is affecting any other part of the body.
However, there is are no recommended particular staging systems for adult brain tumors. This is mostly because brain tumors don’t usually spread beyond the central nervous system. The grading system typically used is based on specific features of the tumor and on how malignant it is. The brain tumors are hence classified on the basis of their extent of growth predicted.
The stage of cancer plays an important role in the determination of the prognosis of the brain tumor –
To decide what is the best treatment for the patient’s brain tumor, both the type and grade of the tumor must be determined. The factors that help doctors determine the appropriate brain tumor treatment plan and a patient’s prognosis:
- Tumor histology – A sample of the tumor is removed for analysis. Its histology will include the type of tumor, the grade, and the molecular features that will predict its speed of growth. Based on all these factors, doctors understand how the tumors behave.
These factors also help in determining the choice of treatment options.
The grade helps in understanding certain characteristics of the tumor that can be linked with specific outcomes.
Tumors that grow more quickly are of a higher grade. Mostly the lower the grade, the better the outcome of the treatment plan.
Specifically for glial tumors, the grade is determined after the tumor cells are examined under the microscope, according to the following criteria:
- Grade I – These are slow-growing and don’t spread. Usually, they can be cured with surgery.
- Grade II – These are less likely to grow and spread, but their chances of recurrence are very high.
- Grade III – They are more likely to have rapidly dividing cells. But given that they don’t have any dead cells, their chances to spread are low.
- Grade IV – The cells in this type of tumor are actively dividing. They grow very rapidly and can spread to different parts of the body.
- Age –
A person’s age and their level of functioning are called functional status. Whenever a prognosis is made for a brain tumor treatment, the lesser the age means the better will be the functional status. This gives a better prognosis.
- Symptoms –
The prognosis also depends on the symptoms the patient portrays. Depending on the severity of the symptoms, and the duration the outcome can be determined.
- The extent of tumor residual –
The surgery done to remove a tumor is known as resection. Depending on how much tumor is left behind after the surgery the prognosis is made. This leftover tumor is called the residual tumor. A person has better chances of f=of survival if the tumor is completely removed. There are 4 classifications:
- Gross total: The entire tumor was removed.
- Subtotal: Large portions of the tumor were removed.
- Partial: Only part of the tumor was removed.
- Biopsy: Only a small part is taken to be used for a biopsy.
- Tumor location –
Any part of the brain can have a tumor. Some tumor locations are more dangerous than the others, therefore the location is very specifically related to the staging.
- Molecular features –
Certain genetic mutations found in the tumor help in determining the grades and stage, including IDH1, IDH2, MGMT, and a 1p/19q co-deletion.
- Metastatic spread –
A tumor that is in the brain or spinal cord rarely spreads to other parts of the body in adults. But it is more likely to spread to the Spinal Column of the patient. This explains the poorer prognosis.
- Recurrent tumor –
A recurrent tumor results in a poorer prognosis and tells that the stage is high.
The cost for brain tumor surgery in India depends on the type of treatment and grade at which cancer is diagnosed. The following are the basic stages and grades –
- Staging –
Staging means how far has cancer spread from where it began. Tumors that begin in the brain are not staged usually, because their spread to other parts of the body is rare.
- Grading –
Brain Tumors grading is done from1 to 4, as classified by the World Health Organization (WHO).
- Grade 1: The cells are identical to normal brain cells, and they grow slowly.
- Grade 2: The cells look different from the brain cells under a microscope.
- Grade 3: The abnormal cells grow actively (anaplastic). Their microscopic image is also very different from the normal cells.
- Grade 4: The tumor is growing and spreading to other parts of the brain.
Cells from low-grade tumors (grades 1 and 2) are very normal looking, and they grow slowly as compared to grade 3 or 5. Over the course of time, the low-grade tumors may become a high-grade tumor.