The Children's Tumor Foundation
10/09/2026 | Press release | Distributed by Public on 10/09/2026 08:11
New CTF-Supported Research Provides a Clearer Picture of Cancer Risk in NF1
People living with NF1 have long been known to face an increased risk for certain cancers. But important questions remain, including how that risk changes throughout a person's lifetime, whether having one cancer increases the likelihood of developing another, and how breast cancer risk changes as women with NF1 age.
A CTF-supported study led by Roope Kallionpää, PhD, Sirkku Peltonen, MD, PhD, and Juha Peltonen, MD, PhD, and their colleagues in Finland is providing a clearer picture.
Published in the Journal of the National Cancer Institute, the study draws on decades of data from Finland's population-based NF1 cohort, one of the world's most comprehensive resources for understanding the long-term health of people living with NF1.
The findings provide new insight into cancer risk across the lifespan and reinforce the importance of continued research to inform appropriate screening, counseling, and care for people with NF1.
Following NF1 across a lifetime
Some of the most important questions about NF can't be answered in a year or even several years.
To understand something like lifetime cancer risk, researchers need to follow large groups of people over decades. That is especially challenging in a rare condition like NF1.
Researchers in Finland have been building and studying a population-based NF1 cohort for years. In this latest study, they expanded the cohort to include 1,811 people with confirmed NF1, with more than 30,000 person-years of follow-up between 1987 and 2020.
By linking that cohort with Finland's nationwide cancer registry, the research team was able to examine not only the occurrence of first cancers, but also what happened to people who had already experienced cancer.
What did researchers learn?
The study confirmed that people with NF1 have a higher overall incidence of cancer than the general population, and that the cumulative risk of cancer continues to increase throughout life.
But researchers also found some reassuring news.
Among people with NF1 who had already experienced a cancer, having that first cancer did not, overall, predict a greater risk of developing a second primary cancer beyond the cancer risk already associated with NF1.
The researchers caution that some subgroups may still be particularly susceptible to developing multiple primary cancers, an area that will require further study.
"Understanding the overall patterns of cancer risk over age forms the basis of efficient surveillance. It is important that individuals with NF1 and clinicians are aware of the risks associated with NF1, as the timely detection of cancers improves treatment outcomes."
Juha Peltonen, MD, PhD
Professor Emeritus, University of Turku, Finland
An important finding about breast cancer risk
The study also provides important new information about breast cancer in women with NF1.
Previous research has established an increased risk of breast cancer in women with NF1, particularly at younger ages. The new study shows that the increased incidence continues beyond age 50.
Researchers estimated the lifetime risk of breast cancer among women with NF1 at 20.9% and found significantly elevated incidence both before age 50 and among women ages 50 and older.
The findings support the classification of NF1 as a moderate-risk breast cancer predisposition gene across the lifespan, rather than a risk concentrated only in younger adulthood.
This does not, by itself, change current screening recommendations. But better understanding when and how cancer risk changes over a person's lifetime can provide important evidence for future discussions about screening, risk assessment, and clinical care.
People with NF1 should talk with their healthcare providers about their individual risk factors and the screening recommendations appropriate for them.
Why long-term investment matters
This research also demonstrates something fundamental about progress in a rare disease: some answers take time.
CTF's research strategy includes investments across the entire path toward better outcomes for people with NF, from understanding the fundamental biology of NF and identifying new drug targets to clinical trials, patient registries, and long-term studies that can improve care today.
Longitudinal research is an important part of that work.
By supporting research programs that follow people with NF over many years, CTF helps researchers answer questions that shorter studies simply cannot. How does risk change as people age? Who may need closer monitoring? Are there groups of patients who face different risks? And how can that knowledge ultimately inform better care?
The Finnish NF1 cohort demonstrates the value of sustaining that work over time. With each additional year of follow-up, researchers can build a more complete picture of NF1 across a lifetime and generate evidence that can help clinicians and patients make more informed decisions.
For people living with NF1, progress isn't only about finding new treatments. It's also about understanding NF well enough to anticipate risks, improve care, and help people live longer, healthier lives.
Read the research
The study, Cancer incidence and the risk for multiple primary cancers in neurofibromatosis type 1, was published in the Journal of the National Cancer Institute in August 2026.
READ THE FULL PUBLICATION
The research was supported by the Children's Tumor Foundation, Cancer Foundation Finland, Päivikki and Sakari Sohlberg Foundation, Turku University Hospital, and HUS Helsinki University Hospital.
The Children's Tumor Foundation published this content on October 09, 2026, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on October 09, 2026 at 14:11 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]