Information about MGMT and 1p/19q Testing
You may have been told your tumour will be tested for MGMT or/and 1p/19q. These tests investigate the genetic background of the tumour. The results of each test can be used in diagnosis and treatment decisions for the individual, improving your care and outcomes.
Eligibility for testing
The MGMT and 1p/19q tests will only be relevant to some people with brain tumours.
Firstly, they can only be performed where a biopsy has been performed, and biopsy material can be obtained and analysed (it does not matter how long ago the biopsy was performed).
Secondly, they are each only relevant to certain tumour types. These are indicated by ‘X’ in the table below. MGMT methylation test relevant to all anaplastic gliomas (WHO Grades III and IV) 1p/19q test is relevant to certain tumour types as below.
| DIAGNOSIS | GRADE | MGMT | 1p/19q |
|
Pilocytic astrocytoma |
WHO grade I | ||
|
|
WHO grade II | ||
| WHO grade III | X | ||
|
Oligodendroglioma |
WHO grade II | X | |
|
Anaplastic Oligodendroglioma |
WHO grade III | X | X |
|
Oligoastrocytoma |
WHO grade II | X | |
|
Anaplastic Oligoastrocytoma |
WHO grade III | X | X |
|
Glioblastoma |
WHO IV | X | (X*) |
* In some circumstances, 1p/19q test will be carried out on glioblastomas.
What the tests are for and why they might be useful
The MGMT gene encodes a protein that is involved in DNA repair, and this protein interferes with the action of certain 
Chemotherapy drugs. The new test will determine the activity levels of the protein, and therefore can indicate whether these drugs are likely to be effective or not.
The 1p/19q test – this looks at two genetic changes on two chromosomes (numbers 1 and 19), to see whether they are complete or whether they have lost one of the two alleles (Loss of heterozygosity, LOH). Loss of these sections of the chromosomes in tumour cells is associated with improved outcomes. It can also be used to aid diagnosis (for example sometimes where there is ambiguity over the tumour type), and in treatment decisions (because sensitivity to chemotherapy can be affected).
The tests might provide information that can be used to influence your treatment and diagnosis, but the research on these is still at an early stage and correlations with the success of different treatments are still being established.
What is the process for having the test(s) done?
The first step is to speak to your neuro-oncologist and ask if s/he thinks the test(s) might be of benefit.
They might then refer you for the test at the NHNN on the NHS - for this your biopsy sample will be sent to the NHNN. (The neuro-oncologist has to contact the neuropathologist at the hospital where the biopsy operation was carried out. The pathologist holds the preserved tissue and will be asked to send material (paraffin blocks) to the Division of Neuropathology at the NHNN and arrange for the test to be undertaken.)
If the neurooncologist decides not to refer you, you may need to think about whether you would like to pursue the test by other means. Ask the neurooncologist what they think about you having the test, as they may have good reason for thinking the test would be inappropriate or not beneficial in your case.
If you wish to pursue the test outside the NHS, you could investigate whether it would be covered by any private medical insurance that you may have –contact the insurer and proceed from there. Otherwise, you could be tested privately and pay yourself. The costs at NHNN are:
The fees for patients with private insurance (e.g. BUPA):
- £760 for 1p/19q
- £400 for MGMT
The fees for patients who pay themselves or for patients with NHS insurance:
- £400 for 1p/19q (“provider to provider”, i.e. within the NHS)
- £280 for MGMT methylation (“provider to provider”, i.e. within the NHS)
This information has been provided by the National Hospital of Neurology and Neurosurgery (NHNN) and the Samantha Dickson Brain Tumour Trust.
| < Prev |
|---|