Management Approach for Neurofibromas
The management of neurofibromas should follow a multidisciplinary approach with specialized NF1 clinic coordination, focusing on observation for asymptomatic lesions and surgical intervention for symptomatic or concerning neurofibromas. 1
Initial Assessment and Monitoring
- Annual general medical evaluation should include questions about signs and symptoms of malignant peripheral nerve sheath tumor (MPNST), chronic pain, and bothersome cutaneous neurofibromas 1
- Physical examination should assess for concerning features such as progressive severe pain, changes in tumor volume, or new unexplained neurologic symptoms 1
- Consider baseline MRI of known or suspected nonsuperficial plexiform neurofibromas 1
- For newly diagnosed plexiform neurofibromas, close observation with serial imaging evaluations is recommended since many will not progress or cause significant symptoms 1
Management of Asymptomatic Neurofibromas
- Observation is the standard approach for asymptomatic neurofibromas without concerning features 1
- Regular monitoring should continue as part of routine NF1 care 1
- For small asymptomatic lesions, surveillance imaging may be appropriate rather than immediate intervention 1
Indications for Intervention
- Symptomatic neurofibromas (pain, functional deficit, cosmetic concerns) 1
- Visual decline or other sensory/motor deficits 1
- Progressive tumor growth that may soon invade critical structures 1
- Rapidly growing tumors (raising concern for malignant transformation) 1
- Progressive disfigurement affecting quality of life 1
Diagnostic Workup for Concerning Lesions
- For concerning lesions, obtain at least 6 core biopsies using 14-18G needles, targeting radiologically concerning areas 1
- Histologic evaluation should assess for cytologic atypia, loss of neurofibromatous architecture, hypercellularity, mitotic count, and necrosis 1
- Immunohistochemical and molecular studies should be performed to evaluate for features of atypical neurofibromatous neoplasm of uncertain biologic potential (ANNUBP) or MPNST 1
- FDG-PET or diffusion-weighted MRI may help identify concerning areas for biopsy 1
Surgical Management
- For symptomatic cutaneous or nodular neurofibromas, complete surgical excision is the treatment of choice 2
- For deep-seated nodular plexiform neurofibromas, enucleation while preserving nerve fascicles should be attempted first 2
- En bloc resection may be necessary when the parent nerve is entrapped by the tumor 2
- For adults with plexiform neurofibromas, a more definitive surgical approach might be considered as these lesions are less likely to have continued growth compared to children 1
- Multiple surgical procedures may be required for long-term tumor management, particularly for head and neck lesions 1
Special Considerations
- Balance present function with the risk to future function imposed by surgical intervention 1
- Radiation therapy should be avoided as it is a known risk factor for malignant transformation 1
- For unresectable or symptomatic tumors, medical therapies may be considered 3
- Patients with NF1 should be evaluated by and receive care coordination with a specialized NF1 clinic 1
- Gastrointestinal manifestations, including gastrointestinal stromal tumors (GISTs), require specific surveillance and management approaches 4
Warning Signs for Malignant Transformation
- Progressive severe pain 1
- Rapid increase in tumor size 1
- Changes in tumor volume 1
- New unexplained neurologic symptoms 1
- Decreased apparent diffusion coefficient (ADC) on diffusion-weighted MRI 1
- Increased avidity on FDG-PET 1
Follow-up Recommendations
- Regular follow-up with a multidisciplinary team including specialists in neurology, oncology, surgery, and genetics 1
- Annual general medical evaluation to monitor for NF1-related complications 1
- Patient education regarding warning signs of malignant transformation 1
- Consider referral to specialized NF1 clinic for optimal care coordination 1