- Patients must have a documented germline NF1 mutation in a Clinical Laboratory Improvement Amendments (CLIA) certified laboratory or a diagnosis of NF1 based on clinical National Institutes of Health (NIH) consensus criteria of at least one other diagnostic criterion in addition to the presence of a PN; NF1 mutation analysis will be performed on germline deoxyribonucleic acid (DNA) as described by Messiaen & Wimmer; histologic confirmation of tumor is not necessary in the presence of consistent clinical and imaging findings, but should be considered if malignant transformation of a PN is clinically suspected; additional criteria are as follows: