Management and Treatment of Neurofibromatosis

Introduction to Neurofibromatosis Management

The American College of Medical Genetics recommends a specialized multidisciplinary approach coordinated through an NF clinic, with regular monitoring for complications and early intervention for symptomatic manifestations to reduce morbidity and mortality 1, 2

Regular evaluation by a specialized NF1 clinic is strongly recommended for all patients, including annual physical examination to detect new or changing lesions, and age and gender-specific health screening 1, 2, 3
Ophthalmologic evaluation for orbital-periorbital plexiform neurofibromas (OPPNs) is recommended, with highest risk of growth before age 8 4, 5, 6
Monitor for signs of malignant transformation: progressive severe pain, changes in tumor volume, new unexplained neurologic symptoms 1, 2

Indications for intervention in plexiform neurofibromas include visual decline or risk to vision, progressive tumor growth, new or worsening functional deficits, and progressive disfigurement 7
MEK inhibitor selumetinib has shown promising results with tumor volume decreases ≥20% in clinical trials for plexiform neurofibromas 8, 9

Pregnancy requires referral to a high-risk obstetrician, and patients should be educated about 50% offspring recurrence risk 1, 2
Preimplantation genetic diagnosis (PGD) and prenatal diagnosis are available options for patients with neurofibromatosis 1, 2

A core team including medical genetics, neurology, oncology, ophthalmology, orthopedics, and dermatology is recommended for multidisciplinary care, with additional specialists as needed for specific manifestations such as OPPNs or GI manifestations 1, 2, 4, 6, 3

Selumetinib is FDA-approved for children aged 2 years and older with NF1 who have symptomatic, inoperable plexiform neurofibromas, producing clinically meaningful tumor shrinkage and functional improvement with an acceptable safety profile, as recommended by the American College of Medical Genetics and Genomics 10, 11
The National Comprehensive Cancer Network recommends selumetinib for tumors that are surgically inoperable 10, 11

Early intervention with selumetinib may prevent progression and facial disfigurement in children with established but small orbital-periorbital plexiform neurofibromas, according to the American Academy of Ophthalmology 12, 13

Trametinib can be used as an alternative MEK inhibitor when selumetinib is unavailable, with demonstrated efficacy in plexiform neurofibromas, as suggested by the National Cancer Institute 10, 11

Cabozantinib, a receptor tyrosine kinase inhibitor, has shown activity in patients aged 16 years and older with NF1 plexiform neurofibromas, according to the National Comprehensive Cancer Network guidelines 14
It remains unknown whether MEK inhibitors modify the risk of transformation to atypical neurofibromatous neoplasm of uncertain biological potential (ANNUBP) or malignant peripheral nerve sheath tumor (MPNST), mandating close clinical monitoring throughout treatment, as recommended by the American College of Medical Genetics and Genomics 14

Screening with pain-interference scales should be implemented routinely, with referral to pain clinics employing both pharmacologic and non-pharmacologic approaches, as suggested by the American Academy of Pain Medicine 15
NF1-associated migraine, seizures, and sleep disorders should be treated with standard medications used in the non-NF1 population, according to the American Academy of Neurology 15 and the American College of Medical Genetics and Genomics 16

In advanced and metastatic MPNST, doxorubicin plus ifosfamide produces response rates of approximately 21% in multi-institutional retrospective studies, as reported by the National Cancer Institute 17
Surgery remains the cornerstone of treatment for high-grade MPNST, with the aim of achieving clear margins, demonstrating benefit even for large abdominal tumors, as recommended by the Society of Surgical Oncology 17
Adjuvant chemotherapy and radiation may have a role in some non-metastatic MPNST patients, though randomized studies are lacking, according to the National Comprehensive Cancer Network 17

Oral estrogen-progestogen or pure progestogen preparations appear safe, with 89% of women reporting no associated neurofibroma growth, as reported by the American College of Obstetricians and Gynecologists 16
High-dose depot contraceptives containing synthetic progesterone should be avoided, as 3% of women reported significant tumor growth with these formulations, according to the American College of Medical Genetics and Genomics 15 and the American College of Obstetricians and Gynecologists 16

Early use of the MEK inhibitor selumetinib in children < 8 years with small orbital‑periorbital plexiform neurofibromas can prevent tumor progression and facial disfigurement. 18

Complete surgical resection with clear margins is the cornerstone of curative treatment for high‑grade MPNST, even when the tumor is large and located in the abdomen. 19
Adjuvant chemotherapy and radiation may be considered for selected non‑metastatic MPNST patients, although no randomized trials have confirmed benefit. 19

Clinicians should vigilantly monitor NF1 patients for malignant transformation, looking for progressive severe pain, rapid tumor growth, new unexplained neurologic symptoms, and deep truncal plexiform neurofibromas. 19
Magnetic resonance imaging (MRI) is the preferred modality for routine NF1 surveillance because it avoids ionizing radiation, which itself increases MPNST risk. 19
18F‑FDG PET/CT identifies NF1‑associated MPNST with a sensitivity of 0.89 and specificity of 0.95; an SUVmax ≥ 3.5 should trigger biopsy for definitive diagnosis. 19

Disease progression does not cease after the second decade of life; NF1 patients can experience continued tumor growth into late adulthood. 18
Standard cytotoxic chemotherapy has not demonstrated benefit for plexiform neurofibromas and carries a risk of treatment‑induced secondary malignancies due to its mutagenic nature. 18