We definitely don’t want children to get sunburned, we also don’t really like them to get suntanned much. That’s true, in general, for skin and dermatology in children. This is the general advice that we give to all our patients.

As for the role of sunlight in CMN, nobody has done a study as to whether UV light and your exposure to sunshine makes a difference to your chance of getting CMN. CMN develops in the brain first, it’s not something that is affected by UV light.

It is possible that the amount of sunlight you are exposed to as a child might make a difference to your chance of getting Melanoma as an adult, and that is just the same for all of us.

Sun exposure in childhood is important for your chance of getting Melanoma later in life, so in general we would like to avoid that if possible- to avoid sunburns and suntan where you can.

This answer has been taken from a Q&A zoom session with Professor Veronica Kinsler, recorded in April 2020.
Please note this is an accurate answer at the time of recording. However, due to the continuing advancement in CMN research, it is important to seek current guidance and advice from a medical professional or by contacting Caring Matters Now.  You can watch the full recorded session here.

If you only have one CMN then yes, a smaller one, has less chance than a larger one. However, if you only have one CMN the chance of getting Melanoma at all in the CMN is very low in your lifetime.

If you have lots of CMN, to some degree it matters but we have found is it is not as important as the MRI scan finding. If your MRI scan is normal your overall risk of getting Melanoma in childhood, even with lots of CMN, is still low (1 to 2%).

If you have some brain abnormalities, it probably doesn’t matter what size your nevi is. We don’t know that for sure, but it’s the abnormal scan that matters from what we understand. This finding is likely to change overtime.

This answer has been taken from a Q&A zoom session with Professor Veronica Kinsler, recorded in April 2020.
Please note this is an accurate answer at the time of recording. However, due to the continuing advancement in CMN research, it is important to seek current guidance and advice from a medical professional or by contacting Caring Matters Now.  You can watch the full recorded session here.

If you have an MRI scan in the first year of life which is normal, your chance of developing melanoma seems to be lower than in people who have abnormalities seen on the brain MRI. It is not clear why this, one of the most obvious reasons is that a lot of the melanoma that develops in childhood starts in the brain or spinal cord. Because of that, it might mean that if you can see abnormalities in the brain, on the scan, that maybe that increases your chance. It is clear from the data that if you have a normal scan, in the first year of life, you have lower chance of getting melanoma, at least in childhood. We don’t know if that’s true into adulthood as we only have data from a childhood cohort, up to the age of about 18 years old.

Exact risks are difficult to give people as it depends on your individual CMN and scan.
The most common finding on a scan is something which we call ‘Intraparenchymal Melanosis,’ this is where little groups of melanin containing cells- a bit like little nevi are seen inside the brain itself. This probably doesn’t increase your chance of Melanoma much at all. What seems to be more of an issue is whenever you have problems along the coating of the spine or brain, or if there are many different structural problems in the brain.

These are much rarer findings, but these more complicated abnormalities increase the risk of Melanoma in childhood. We are lucky in the UK because we have a system, and because of work done by my predecessor, there is already a cohort established meaning we’ve been able to follow people up for a long time. What we have found is that people who have an abnormal scan, in the first year of life, have a 10-15% chance of getting Melanoma in childhood. However, this won’t be the same for everybody as it depends uniquely on what is found on your MRI scan. The vast majority of cases will not get Melanoma.

This answer has been taken from a Q&A zoom session with Professor Veronica Kinsler, recorded in April 2020.
Please note this is an accurate answer at the time of recording. However, due to the continuing advancement in CMN research, it is important to seek current guidance and advice from a medical professional or by contacting Caring Matters Now.  You can watch the full recorded session here.

At the moment, as far as we know, there is no difference in the chance of getting Melanoma depending on which gene is causing your CMN.

We also know that there doesn’t seem to be any difference in the chance of having neurological problems with different genes. This seems to be something that can happen with any of the types of genes.

Going forward, as we understand more that may change. Our understanding at the moment is that you don’t need routine gene testing for CMN because it doesn’t change your chance of getting problems with the brain or your chances of getting Melanoma.

The one time that we would suggest getting a test for either the NRAS or BRAF gene, is if somebody actually develops Melanoma or where Melanoma is strongly suspected. The reason that it’s worth testing for the gene is because it changes the type of treatment that you might be given. This is a very well-known test and is very well understood by dermatologists and oncologists already, so you would automatically be offered that testing if someone thought you had Melanoma.

This answer has been taken from a Q&A zoom session with Professor Veronica Kinsler, recorded in April 2020.
Please note this is an accurate answer at the time of recording. However, due to the continuing advancement in CMN research, it is important to seek current guidance and advice from a medical professional or by contacting Caring Matters Now.  You can watch the full recorded session here.

No, there is no evidence to tell us that people need to be screened for cancers in general. There are some families who are prone to cancers but we do not know of any connection between that and CMN at the moment.

This answer has been taken from a Q&A zoom session with Professor Veronica Kinsler, recorded in April 2020.
Please note this is an accurate answer at the time of recording. However, due to the continuing advancement in CMN research, it is important to seek current guidance and advice from a medical professional or by contacting Caring Matters Now.  You can watch the full recorded session here.

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