The purpose of the research study is intended to use specimens (such as tissue) and medical information in the Laboratory of Musculoskeletal Oncology at the Van Andel Research Institute for laboratory research in Grand Rapids, Michigan. Small tissue samples of cutaneous neurofibromas will be collected as part of this research. The samples will help researchers learn more about cutaneous neurofibroma and help them better understand NF1. There are many different types of studies, both now and in the future, that can be done using the specimens the investigators receive. These include using the specimens and information to look for new ways to diagnose and treat Neurofibromatosis Type 1 (NF1). The specimens may be used to study how genes affect health and disease, or how genes affect the way a disease or condition responds to treatment. Some of these studies may lead to new products, such as treatments or tests for diseases. Through this study, the investigators hope to find better ways to understand and treat NF1 in the future.

Skin tumors in Neurofibromatosis Type 1 (NF1) are very common and diminish quality of life. Apart from surgery, very few treatment options exist. In comparison to other types of tumors in NF1, skin tumors receive less attention in the research world because they almost never turn into cancer. Under the microscope, skin tumors and plexiform tumors look similar, however they do not share the same growth potential, nor do they appear at the same time during development. These differences suggest that skin tumors are driven by different factors than plexiform tumors.

In this study the investigators will be harvesting CNFs from 3 groups of subjects in order to obtain a minimum of 18 tumors in three size categories: <5mm, 5-10mm, and >1cm. These sizes were selected based on the variable natural history of CNF progression where incipient lesions (typically <5mm) are more numerous and demonstrate a less aggressive growth pattern, whereas the intermediate group (5-10mm) represent a transition state towards growth to larger (>1cm) lesions. Interestingly, CNF growth tends to stall out at 3cm. The investigators plan to do experiments that identify which factors are important to CNF progression, and then find matching drugs that can shrink the tumors.

Inclusion Criteria:

1. Any subject with an established diagnosis NF1 and CNFs. The diagnosis may be based on clinical criteria or genetic testing.
2. Age >18 years.

Exclusion Criteria:

1. Adults with diminished decision-making capacity with no defined legal guardian.
2. Prisoners.
3. Pregnant women.

3) Breastfeeding mothers.

Anyone with an established diagnosis NF1 and CNFs. The diagnosis may be based on clinical criteria or genetic testing.