Topical Imiquimod 5% Cream for Treatment of Cutaneous Neurofibromas in Adults With Neurofibromatosis 1

• Three of the participant's tumors will be treated with imiquimod cream and one tumor (out of all the remaining tumors) will be followed without treatment (control tumor).
• Participants will be given a tube of imiquimod cream and be asked to apply it to the three tumors 5 times per week, for a full 6 weeks (Monday through Friday).
• Participants will be required to come to the hospital for examinations on Week 1, 2, 4 and 6 (+/- 3 calendar days) and after their last dose of imiquimod cream on Weeks 9, 12 and 18 (+/- 5 calendar days. The following tests and procedures will be performed: skin test; vital signs and measurements and photographs of the tumors. Participants will be asked to participate in an optional skin biopsy on Week 4 and research blood tests wil lbe taken on Day 1.

Inclusion criteria

• Patients must have a diagnosis of NF1 based on NIH criterial with two or more of the following characteristics:

• six or more cafe-au-lait macules (1.5cm or greater in size)
• skin fold freckling in the axilla or groin
• optic pathway glioma
• two or more Lisch nodules of the iris
• distinctive bony lesions such as dysplasia of the sphenoid wing or of a long bone such as the tibia
• two or more neurofibromas of any type of 1 or more plexiform neurofibroma
• first degree relative with NF1
• Participants must have at least four cutaneous neurofibromas on skin exam with the following qualities:

• the lesion must be discrete by clinical exam and must not be contact with another skin tumor
• the lesion must be amenable to measurement with calipers with minimum dimension of 5mm and maximum dimension of 30mm
• the lesions must be located on the trunk, neck, or extremities (excluding the hands and feet) and must be located in an area that can be photographed
• histologic confirmation of tumor type is not required in the setting of compatible clinical setting
• No treatment with an investigation agent for cutaneous neurofibromas within the last 3 months
• 18 years of age or older

Exclusion criteria

• Pregnant and nursing women
• Patients who have had chemotherapy or radiotherapy within 6 weeks prior to entering the study or those who have not recovered from adverse events due to agents administered more than 6 weeks earlier
• Patients may not be receiving any other investigational agents
• History of allergic reactions attributed to compounds of similar chemical or biologic composition to imiquimod
• Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.