A Research Guide for
Neurofibromatosis Type 1

Diagnosis

NF1 is usually diagnosed by recognizing its characteristic features, sometimes confirmed with genetic testing. Many people are diagnosed in childhood because the skin signs appear early.

The features in more depth

Understanding the common features helps you know what is expected and what is not. Café-au-lait macules are flat, evenly colored light-brown patches that are usually present in infancy and often the first sign; having six or more that are large enough is one of the diagnostic criteria. Freckling in the armpits and groin (places that don't normally freckle) typically appears in childhood. Neurofibromas are soft, benign growths along nerves: the common cutaneous (skin) type usually starts to appear around the teenage years and tends to increase with age, and while they are harmless, they can be itchy or affect appearance. Plexiform neurofibromas are different — larger, often present from birth, growing along a length of nerve, and sometimes deep inside the body; these are the ones watched most carefully. Lisch nodules are tiny harmless bumps on the colored part of the eye that an eye doctor can see; they don't affect vision but help confirm the diagnosis. Other possible features include a larger head size, shorter stature, curvature of the spine, and the learning differences discussed elsewhere. Remember: this is a menu of possible features, and any one person has only some of them.

How NF1 is diagnosed

Doctors use a set of established diagnostic criteria: a diagnosis is made when two or more characteristic features are present. These include six or more café-au-lait macules, freckling in the armpits or groin, two or more neurofibromas (or one plexiform neurofibroma), an optic pathway glioma, two or more Lisch nodules (or certain other eye findings), a distinctive bone abnormality, a confirmed change in the NF1 gene, or having a parent with NF1. In young children, not all features may have appeared yet, so the diagnosis sometimes becomes clear over time, and genetic testing can confirm it when needed.

Genetic testing and counseling

Genetic testing can identify the specific NF1 gene change. It is especially useful when the diagnosis is uncertain, in very young children with few features, or for family planning. A genetic counselor can explain the inheritance (each child of an affected person has a 50% chance of inheriting NF1), the fact that about half of all cases arise new (with no affected parent), and the options available, including prenatal testing and preimplantation genetic testing for those planning a family. Because NF1 is so variable, genetic results confirm the diagnosis but cannot predict exactly how someone will be affected.

Conditions that can look similar

A few other conditions can resemble NF1, which is why an accurate diagnosis matters. Legius syndrome causes café-au-lait macules and freckling like NF1, but — importantly — it does not cause neurofibromas, the eye findings, or the tumor risks of NF1, so it has a much more benign outlook; it is caused by a different gene and is distinguished by genetic testing. This is a good-news distinction: someone thought to have mild NF1 may actually have Legius syndrome and a lower-risk condition. Other conditions can also cause multiple café-au-lait spots, and there are related but distinct conditions (such as the schwannomatoses, including what used to be called NF2) that are entirely separate from NF1, with different genes, features, and care. If there is any uncertainty, genetic testing and evaluation by a specialist sort out which condition is present — and that clarity directly shapes what monitoring and counseling are appropriate. So if you've been told you “might have NF1” based only on skin spots, it's reasonable to ask whether genetic testing would clarify the picture.

Questions to ask your doctor

• Which criteria do I (or my child) meet for the diagnosis?
• Would genetic testing add anything useful for us?
• What does this mean for siblings, parents, or future children?
• Who will coordinate our ongoing care?

Treatment & Monitoring

There is no cure for NF1, and most people don't need active treatment for the condition itself most of the time. Care centers on monitoring for complications, treating specific problems when they arise, and, increasingly, using new medicines for certain tumors.

Managing neurofibromas

Most cutaneous (skin) neurofibromas are harmless and don't require treatment, but those that are painful, irritated, or cosmetically distressing can be removed (by surgery or other techniques). Plexiform neurofibromas — the larger, deeper tumors — are watched over time; when they cause symptoms (pain, disfigurement, or pressure on nearby structures) and cannot be fully removed by surgery, medicine may now be an option.

MEK inhibitors — a major advance

A class of medicines called MEK inhibitors can shrink plexiform neurofibromas by targeting the overactive growth signal at the root of NF1. Two are FDA-approved:

• Selumetinib (Koselugo) — first approved in 2020 for children with symptomatic plexiform neurofibromas that can't be completely removed by surgery, and since broadened to cover both children (from age 1) and adults.
• Mirdametinib (Gomekli) — approved in 2025 for both adults and children aged 2 and older with symptomatic, inoperable plexiform neurofibromas. In its main trial, tumors shrank by 20% or more in about 4 in 10 adults and about half of children.

These medicines don't cure NF1 and have side effects (such as skin rash, gastrointestinal effects, and others) that need monitoring, but they have transformed options for people with large, symptomatic tumors. Whether one is right for you is decided with an NF specialist.

If a MEK inhibitor is being considered, it helps to know what treatment involves. These are oral medicines taken on an ongoing schedule, and the benefit — tumor shrinkage and, importantly, improvement in symptoms like pain — usually builds gradually over months rather than appearing right away. Because they work by damping down a growth signal throughout the body, they have side effects to monitor: skin rash (often acne-like) is common, along with nail changes around the fingers/toes, gastrointestinal effects like diarrhea, and less commonly effects on the heart's pumping or on the eyes — so treatment includes regular checks (skin, heart scans, eye exams, and blood tests). Many side effects are manageable with dose adjustments and supportive care. The medicine controls the tumor while it is being taken; tumors can regrow if it is stopped, so the decision about how long to continue is individualized. These are powerful, genuinely helpful drugs for the right situation — symptomatic plexiform neurofibromas that can't be fully removed surgically — and the decision to start, and which one, is made together with an NF specialist who weighs the likely benefit against the side effects for you.

Treating other features

• Optic pathway glioma — many are watched; those threatening vision are treated (traditionally with chemotherapy, and increasingly with MEK inhibitors).
• High blood pressure — checked at every visit and treated; sometimes it has a specific cause that needs investigation.
• Scoliosis and bone problems — monitored and managed by specialists; some bone abnormalities need orthopedic care. NF1 can affect the spine (curvature, or scoliosis) and, less commonly, cause specific bone problems such as bowing or fragility of the lower leg (which sometimes needs orthopedic surgery) or a difference in the bone around the eye. Bone density can also be a bit lower, so attention to bone health (calcium, vitamin D, and activity) is worthwhile. Most of these are managed straightforwardly when watched for, which is why spine checks are part of children's monitoring.
• Learning and attention difficulties — addressed with educational support, accommodations, and (for ADHD) treatment as appropriate.
• Pain — taken seriously and managed, and also evaluated as a possible warning sign (see below).

A note on optic pathway gliomas, because they worry parents. These are tumors of the visual pathway that occur mainly in young children with NF1; many are present without causing any problems and simply need watching, and only some ever threaten vision. That is exactly why young children with NF1 have regular eye exams — not because a problem is expected, but so that the small number that do progress are caught early, when treatment (traditionally chemotherapy, and increasingly the same MEK-inhibitor medicines) can protect sight. Most children with an optic pathway glioma do well. The key message for families is reassuring but actionable: keep up with the scheduled eye checks, and report any new vision changes promptly — the monitoring system is designed to catch issues before they cause lasting harm. As children grow past early childhood, the risk of a new optic pathway glioma falls, and the eye-monitoring schedule is adjusted accordingly.

Learning, attention, and school support

Because learning and attention difficulties affect around half of children with NF1, this deserves its own focus — and it is one of the most rewarding areas to address, because support works. The difficulties are usually specific (such as trouble with visual-spatial skills, organization and planning, reading, or sustained attention) rather than a general intellectual problem, and most children with NF1 have normal overall intelligence. The key is to identify needs early with a proper educational or neuropsychological assessment, rather than waiting for a child to struggle and lose confidence. With that information, schools can put accommodations and an individualized education plan in place, and attention problems (ADHD) can be treated effectively, just as in any other child. Parents are powerful advocates here: requesting evaluation, keeping in touch with teachers, and celebrating strengths all make a difference. Adults with NF1 who have lifelong organizational or attention challenges can also benefit from strategies and, where appropriate, treatment. Addressing the learning side of NF1 is every bit as important as the medical monitoring for long-term wellbeing and independence.

Questions to ask your doctor

• Do any of my tumors need treatment now, or watching?
• Am I (or my child) a candidate for a MEK inhibitor?
• What exactly should prompt an urgent call about a tumor?
• How are my blood pressure, spine, and (for children) eyes being monitored?

Serious Complications, Pregnancy & Trials

This section covers the more serious complications to be aware of, special situations, and the research bringing new options.

Pain and other symptoms — when to speak up

Pain deserves special mention in NF1, for two reasons. First, it is worth treating in its own right: neurofibromas and other features can cause discomfort, and there are good ways to manage pain — you should not have to simply put up with it, so tell your team. Second, and importantly, certain kinds of pain are a warning sign that needs prompt evaluation: pain that is new and persistent, that is deep or unrelenting, that wakes you at night, or that is associated with a lump that is growing or has become hard. This kind of pain doesn't usually mean something serious — but it always deserves to be checked, because it can be the earliest sign of a tumor changing. The same goes for new weakness, numbness, or changes in how a part of the body works. The rule of thumb is simple: don't assume a new or changing symptom is “just NF1.” Reporting it promptly costs little and, in the rare case where it matters, allows treatment at the earliest, most effective stage. Your care team would always rather hear about a symptom that turns out to be nothing than miss one that turns out to be important.

MPNST — the complication to know

A malignant peripheral nerve sheath tumor (MPNST) is a cancer that can develop, usually from a pre-existing plexiform neurofibroma. Over a lifetime, roughly 1 in 10 people with NF1 may develop one, and it is the leading cause of NF1-related death — which is why awareness matters so much. The good news is that early detection saves lives: knowing the warning signs (new or persistent pain, rapid growth, a hard lump, new neurological symptoms) and reporting them promptly allows early imaging (often a special scan called FDG-PET) and biopsy. Treatment is mainly surgery to remove the tumor completely, sometimes with chemotherapy or radiation. This is the single most important reason to stay engaged with monitoring and to never ignore the warning signs.

What monitoring looks like, and why

Because NF1 is so variable and a few complications are serious but treatable when caught early, monitoring is the backbone of care — and understanding it makes it less daunting. For everyone, this generally means a yearly check that includes a look at the skin and any tumors, a blood-pressure measurement, and a review of any new symptoms (especially the tumor warning signs). For children, it adds regular eye exams (to catch an optic pathway glioma early), monitoring of growth and the spine, and attention to learning and development. At the transition into adulthood, some people have a whole-body MRI scan to get a baseline picture of any internal tumors and to help judge future risk. For women, enhanced breast-cancer screening usually begins earlier than in the general population. The schedule is tailored to you — someone with a large internal plexiform neurofibroma will be watched more closely than someone with only a few skin spots. The point of all this is not to make you anxious but to keep you safe: most checks are reassuringly normal, and the system exists so that the rare serious problem is found at its most treatable stage.

Other health risks to monitor

NF1 carries a modestly increased risk of some other tumors and conditions, which is why surveillance is individualized. These can include certain brain tumors, an adrenal gland tumor (pheochromocytoma) that can raise blood pressure, gastrointestinal tumors, and — importantly for women — a higher risk of breast cancer, for which earlier and enhanced screening is recommended (often starting around age 30). Your NF specialist tailors surveillance to your specific features and history. Most people will never develop these, but knowing about them allows sensible, proactive monitoring.

Pregnancy and family planning

Pregnancy is an important consideration in NF1. Neurofibromas can grow or become more noticeable during pregnancy (likely due to hormonal changes), and women with NF1 may have a somewhat higher rate of pregnancy complications, including high blood pressure — so pregnancy is best managed by a team aware of the condition. Because NF1 is inherited (a 50% chance of passing it to each child), genetic counseling is valuable for anyone planning a family, and options such as prenatal testing and preimplantation genetic testing can be discussed. None of this should discourage having children — many women with NF1 have healthy pregnancies — but planning with informed care makes it safer.

Understanding inheritance and what it means

Because NF1 is genetic, families naturally have questions about passing it on. NF1 follows an “autosomal dominant” pattern, which means each child of a person with NF1 has a 50% chance of inheriting the gene change — the same for each pregnancy, regardless of previous children. About half of all people with NF1 are the first in their family to have it, caused by a brand-new gene change; in those cases, the person's parents and siblings are usually not affected, though the person can still pass it to their own children. A crucial point is that inheriting the gene does not tell you how severely someone will be affected — a parent with mild features can have a more significantly affected child, and vice versa — because NF1 is so variable. For anyone planning a family, a genetic counselor can explain all of this in your specific situation and discuss options, which can include prenatal testing during a pregnancy or preimplantation genetic testing (testing embryos before pregnancy) for those who wish to consider it. There is no “right” choice — the aim is simply to give families clear, supportive information to make their own decisions.

>Clinical trials and research

NF1 research is unusually active, and the recent approvals of MEK inhibitors grew directly out of clinical trials:

• Mirdametinib was approved based on the ReNeu trial (NCT03962543), which tested it in children and adults with symptomatic plexiform neurofibromas.
• Selumetinib was approved for children based on the SPRINT trial (NCT01362803), and its benefit in adults was studied in the KOMET trial (NCT04924608).
• Trials continue for new and better tumor treatments, for optic pathway glioma, for MPNST, and for other NF1 features.

It's worth appreciating why NF1 research has moved so quickly. Scientists worked out that the NF1 gene normally puts a “brake” on a specific cell-growth signal (the RAS–MEK pathway), and that without that brake the signal runs too high — driving tumor growth. The MEK inhibitors were designed to step in and damp down that overactive signal, which is exactly why they can shrink plexiform neurofibromas. This understanding has opened the door to testing similar and newer targeted treatments for other NF1 problems — including the cancerous MPNST tumors (a major focus, because better treatments are badly needed there), optic pathway gliomas, and even the cutaneous neurofibromas that affect appearance. Researchers are also studying the learning and attention difficulties. The practical takeaway is that the treatment landscape for NF1 is genuinely expanding for the first time, and clinical trials are how these advances are tested and reach patients — so staying connected to an NF center and to organizations that track trials means you'll hear about relevant new options as they emerge.

Questions to ask your doctor

• What is my personal level of MPNST risk, and how are we monitoring for it?
• What cancer screenings (including breast screening for women) do I need, and when?
• If I'm planning pregnancy, how should we prepare?
• Are there clinical trials relevant to me?

Support & Resources

Below are guidance on living well, support organizations, a glossary, what does not work, and the sources behind this guide.

Working with your care team

Getting the most from NF1 care is partly about how you work with your team. Because so many specialists may be involved, it helps to have one main doctor or NF clinic coordinating — someone who holds the overall picture and your monitoring schedule, so things don't fall through the cracks. Come to appointments with a short list of questions and any new symptoms or changes you've noticed (photos of changing skin lesions, with dates, are genuinely useful). Don't hesitate to ask “what are we watching for, and what should make me call sooner?” — understanding your own plan makes you a more effective partner and reduces anxiety. Keep copies of key results and a simple summary of your NF1 features to share with new clinicians, including in emergencies. And speak up about things that matter to you, whether that's a bothersome visible neurofibroma, pain, worries about your children, or the emotional side of the condition — all of these are legitimate parts of NF1 care. A good team wants this engagement; you are the one constant across all your specialists, and your observations and priorities help steer the care in the direction that's right for you.

Living well with NF1

Beyond medical monitoring, several things help daily life. Keep up with your regular check-ups and know your personal warning signs — this is the foundation of safety. For visible features, remember that treatment options exist for bothersome neurofibromas, and support is available for the emotional impact of a visible condition. For children, advocate early for school assessment and support if learning or attention is affected — this is one of the highest-value things a parent can do. Attend to emotional wellbeing: living with an unpredictable condition can be stressful, and counseling, peer support, and NF community connections genuinely help. And build a relationship with an NF clinic or knowledgeable specialist who can coordinate the multispecialty monitoring NF1 needs.

For parents of a child with NF1

If your child has just been diagnosed, the diagnosis can feel frightening — but there is a lot you can do, and most children with NF1 grow up to live full lives. A few priorities help. First, set up regular check-ups, including the yearly eye exams young children need (to catch an optic pathway glioma early) and blood-pressure and spine checks. Second, watch development and learning: because about half of children with NF1 have learning differences or attention difficulties, early educational assessment and support — well before problems become entrenched — is one of the most valuable things you can do, and many children thrive with the right accommodations. Third, learn the warning signs (new or persistent pain, a fast-growing or hard lump, new weakness) so you know when to call, without living in fear of every bump. Fourth, support your child's self-esteem, especially around visible skin features, and answer questions honestly and age-appropriately. Finally, connect with an NF clinic and with other families through the Children's Tumor Foundation — both the expert coordination and the community make the journey far less daunting. You are your child's best advocate, and you don't have to do it alone.

The emotional and visible side

NF1 is not only a medical condition — it can carry an emotional and social weight that deserves acknowledgment. Visible neurofibromas or skin features can affect self-image and invite unwanted questions or comments, which can be hard at any age and especially in adolescence. The uncertainty of a variable, lifelong condition — not knowing exactly what will happen — can cause anxiety. None of this is a sign of weakness, and it is worth treating as seriously as the physical features. Things that help include counseling or therapy, connecting with others who have NF1 (in-person or online communities through NF organizations), being open with trusted people, and remembering that bothersome visible neurofibromas can often be treated. For many, focusing on what they can control — staying on top of monitoring, treating specific problems, building a supportive network — restores a sense of agency. If low mood or anxiety becomes persistent, tell your care team; mental-health support is part of good NF1 care, not separate from it.

Practical day-to-day strategies

Some practical habits make living with NF1 smoother. Keep a simple personal record of your NF1 features, your monitoring schedule, current medicines, and the warning signs — useful for new doctors and for emergencies. Track any changes in tumors (a photo with a date can help) so you can show your team what's new, and don't hesitate to call about the warning signs rather than waiting for the next routine visit. Stay on top of the routine but easy-to-forget basics: blood-pressure checks, children's eye exams, and (for women) breast screening on schedule. For visible features, know that bothersome neurofibromas can often be treated, and that clothing, skin care, and — if you wish — cosmetic options are reasonable to discuss. Build your team and support network: a coordinating NF clinician, the specialists you need, and connections through NF organizations. And take care of your mental health alongside the physical — the stress of a variable condition is real, and support helps. None of these are complicated, but together they keep you safe and in control.

Mountain West / Utah

• University of Utah Health & Primary Children's Hospital (Salt Lake City) — neurology/neuro-oncology, medical genetics, ophthalmology, and pediatric specialty care relevant to NF1; appointments via University of Utah Health (801-585-7575).
• Huntsman Cancer Institute — for tumor-related care and cancer-risk surveillance.
• Intermountain Health — regional pediatric and adult specialty services.
• George E. Wahlen VA Medical Center (Salt Lake City) — for eligible veterans.

National organizations

• Children's Tumor Foundation (CTF) (ctf.org) — the leading NF organization: education, an NF Clinic Network directory, research and trial information, and support; helpline available.
• Neurofibromatosis Network (nfnetwork.org) — advocacy and patient support.
• NF specialty clinics — the CTF maintains a directory of recognized NF clinics offering coordinated multidisciplinary care.
• National Cancer Institute / NINDS and ClinicalTrials.gov — for research and trial information.

Getting good care wherever you are

NF1 benefits from coordinated, specialized care, but not everyone lives near an NF clinic — and there are ways to get good care regardless. Even an occasional visit to a recognized NF center (the Children's Tumor Foundation maintains a directory) can establish a clear monitoring plan that your local doctors then help carry out, and many centers offer telehealth consultations. The essentials that should happen wherever you are seen are: confirming the diagnosis, the age-appropriate monitoring (eye exams for children, blood pressure, spine, development), and — above all — that you and your local clinicians know the MPNST warning signs and act on them promptly. Keep your own brief summary of your NF1 features and monitoring plan to share with any new doctor. National organizations can help you find experienced clinicians, navigate insurance and access to the newer medicines, and connect with the NF community and clinical trials. Because NF1 research and awareness are growing quickly, access to knowledgeable care and to effective treatments is improving over time.

International access

NF1 is recognized worldwide, and the foundation of care — clinical diagnosis, monitoring, and treatment of complications — is achievable wherever genetics, neurology, ophthalmology, and oncology services exist; international consensus guidelines (including the European ERN GENTURIS tumor-surveillance guidance) inform care across regions. The MEK inhibitors selumetinib (Koselugo) and mirdametinib (sold as Gomekli in the United States and as Ezmekly in the European Union) are approved in the United States and a growing number of countries, though availability and exact indications vary by region; access to specialized NF clinics also differs. The universal priorities are the same everywhere: confirm the diagnosis, establish appropriate surveillance (especially eye monitoring in children and awareness of the MPNST warning signs), and connect with a knowledgeable center.

What does not work

Being clear about limits helps. There is currently no cure for NF1 and no treatment that prevents neurofibromas from forming. MEK inhibitors can shrink certain tumors but do not eliminate them or work for everyone, and they are reserved for specific situations (symptomatic, inoperable plexiform neurofibromas) rather than for all NF1 features. Removing every neurofibroma is neither possible nor necessary — surgery is targeted to tumors that cause problems. And no supplement or alternative therapy treats NF1 or prevents its complications; be cautious of products marketed as cures. Importantly, ignoring the MPNST warning signs — assuming pain or a growing lump is “just NF1” — is a dangerous mistake; prompt evaluation is what protects you.

A hopeful, realistic close

Living with NF1 means holding two truths together. It is a serious, lifelong genetic condition with the potential for significant complications — that is real, and it is why monitoring and awareness matter. But it is also a condition where most people do well, where the majority of features are mild or treatable, where serious problems are uncommon and most treatable when caught early, and where the treatment landscape is genuinely expanding for the first time in decades. The people who do best are not those with the “mildest” NF1 by luck, but those who stay engaged: keeping up with monitoring, knowing and acting on the warning signs, treating specific problems as they arise, supporting children's learning early, and staying connected to knowledgeable care and a supportive community. You did not choose NF1, and nothing caused it — but you can shape how it is managed. Use this guide as a practical companion, lean on your care team and on organizations like the Children's Tumor Foundation, and remember that a full, meaningful life with NF1 is not just possible but typical.

Key sources

Based on the revised international diagnostic criteria for NF1; international and European (ERN GENTURIS) NF1 tumor-surveillance and management guidance; standard genetics, neurology, ophthalmology, and oncology references on NF1 features, MPNST and optic-pathway-glioma surveillance, and complications; and the MEK-inhibitor approvals and trials — selumetinib (Koselugo; SPRINT, NCT01362803; KOMET, NCT04924608) and mirdametinib (Gomekli; ReNeu, NCT03962543) — plus ClinicalTrials.gov registry data. This guide is educational and is not a substitute for advice from your own medical team.