Location, symptoms, and management of plexiform neurofibromas in 127 children with neurofibromatosis 1, attending the National Complex Neurofibromatosis 1 service, 2018–2019

Abstract

We report on the location, symptoms, and management of plexiform neurofibroma (PN) in children with Neurofibromatosis Type 1 (NF1) attending the 2 National Complex Neurofibromatosis 1 Services at Guy's and St. Thomas' NHS Foundation Trust, London and St Mary's Hospital, Manchester. Retrospective data collection was performed from patient chart reviews from April 2018 to April 2019. There were 127 NF1 patients with PN, age range 0.8-17.0, mean age was 9.9 years (SD ± 4.2 years). The main location of the PN was craniofacial in 35%, and limb in 19%. Disfigurement was present in 57%, pain in 28%, impairment of function in 23%,and threat to function in 9% of children. Fifty-four percent of patients were managed conservatively, 28% surgically, and 19% are either taking or due to start a mitogenactivated protein kinase kinase (MEK) inhibitor (selumetinib or trametinib), either through a clinical trial or compassionate usage scheme. This national study provides a comprehensive overview of the management of children with PN in an era where new therapies (MEK inhibitors) are becoming more widely available. We anticipate that there will be a shift to more patients receiving MEK inhibitor therapy and combination therapy (surgery and MEK inhibitor) in the future.

Neurofibromatosis Type 1-Associated Plexiform Neurofibromas of the Face and Adjacent Head Regions: Topography of Lesions and Surgical Treatment Data of 179 Patients

“…Topographic analysis of craniofacial PNF tumor spreads is an important contribution to assessing the treatment needs of these patients. Among NF1-associated PNF, craniofacial PNF requires the most surgical treatment [ 3 , 13 ]. Both classifications of the facial surface used for topographic evaluation show PNST frequency symmetry illustrated by the tumor-affected regions marked with the same intensity of color on both sides, namely eyes/orbits, temples, cheeks, and lateral forehead.…”

“…Likewise, the diagnosis of PNF was not further specified. Other studies suggest that craniofacial PNF is among the most common tumor sites in NF1 patients requiring surgical intervention [ 3 , 13 ]. However, from clinical judgment, the differences between PNF and diffuse neurofibroma appear to be gradual (Table 2 ).…”

“…Data on the frequency of FPNF are uncertain because the records are based on different sources or evaluation criteria [ 1 , 2 ]. Among the body regions, craniofacial manifestations of PNF are frequently detected [ 3 ].…”

Diagnosis and Treatment of Peripheral and Cranial Nerve Tumors with Expert Recommendations: An EUropean Network for RAre CANcers (EURACAN) Initiative

“…Localized neurofibromas occur as polypoid lesions without any anatomical preference, while diffuse neurofibromas appear as plaque-like lesions mainly in the head and neck region. PN are large, massive lesions with “bag of worms” aspects, close to large spinal roots of the shoulder or pelvic girdle in adult population [ 15 ], while craniofacial site with disfigurement (35%), or location along limbs (19%), in association with pain and impairment of function, are typical of childhood [ 16 ]. The presence of multiple neurofibromas or PN is strongly suggestive of NF1, especially when associated with typical findings (see Section 4 “Genetic tumor syndromes correlated with cranial and peripheral nerve sheath tumors”).…”

Neurofibromatosis type 1-associated plexiform neurofibromas of the neck: topography of lesions and surgical treatment data of 69 patients

“…Clinical diagnosis distinguishes mainly two types of neurofibroma: cutaneous and plexiform (PNF). Unlike cutaneous neurofibromas, which are usually numerous and limited in extent to the integument, reaching a maximum size of only a few centimeters in diameter, PNFs are invasive tumors that often destroy the tissues [ 4 , 7 , 8 ]. PNF can cause significant esthetic disfigurement and functional impairment.…”