Medication Adherence in Children, Adolescents and Adults With Neurofibromatosis Type 1(NF1) on Clinical Treatment Trials

Background: * Neurofibromatosis type 1 (NF1) is a genetic disorder that affects approximately 1 in 3,500 individuals and is associated with a broad variety of symptoms and physical findings. * Plexiform neurofibromas (PN) are histologically benign tumors which occur in 25-50% of patients with NF1 and can lead to significant morbidity. * Oral therapeutic options for the treatment of plexiform neurofibromas are being actively developed, however early clinical data indicate that prolonged treatment over the course of months to years will likely be needed to maintain clinical efficacy * Long-term medication adherence is an ongoing challenge for patients with many types of chronic illness, and clinical experience makes us strongly suspect patients with NF1 will likely have this issue as well. * In other diseases, such as human immunodeficiency virus (HIV) and Acute Lymphoblastic Leukemia, decreased medication adherence has been associated with poorer clinical outcomes, and this may be the case for NF1 as well. * The medication event monitoring systems (MEMS\^TM) uses a computerized method of tracking the dates and times of a pill bottle being opened and has been shown to be a more accurate measure of medication adherence than patient diaries or pill counts in other patient populations. * Assessing medication adherence over time in this unique population will be essential for assessing any impact on medical outcomes, identifying potential behavioral interventions, and targeting patients most at risk for nonadherence moving forward. Objective: \- To establish the feasibility of using MEMS\^TM to monitor medication adherence in the NF1 population Eligibility: * Subjects must have a diagnosis of NF1 and be between 3 and 59 years of age * Participants must be enrolled on a clinical trial for an oral medication in pill (tablet or capsule) form directed at the treatment of plexiform neurofibroma(s) Design: * This single-site, longitudinal study will recruit children and adults with NF1 who are currently enrolled in a treatment protocol for a drug targeting PN volume reduction. * MEMS\^TM caps will be used to monitor adherence over time along with patient diaries and pill counts. * Patients with MEMS\^TM cap data indicating \<90% adherence at any study visit (typically across 3 - 6 cycles) will be administered a measure assessing barriers to adherence electronically and will be interviewed to evaluate what factors might contribute to decreased medication adherence and what potential interventions they consider useful.