NF 1 is an autosomal dominant genetic disorder of chromosome 17q11.2 characterized by skin tumors derived from peripheral nerves [2
]. The affected gene is responsible for the production of neurofibromin as a tumor suppressor, possibly through modulation of the oncogenic pathways [2
]. Moreover, Schwann cells were discovered to be the origin of neurofibroma, but a more complicated interplay of multiple cell types, such as mast cells and fibroblasts, was observed in tumor genesis, with important implications for surgical treatment of these tumors [12
Since one of the most devastating consequences of NF 1 is the psychological impact of the cutaneous lesions, it is the main reason for visiting the hospital.
There are various modalities for treatment of cutaneous neurofibromas; however, none is universally accepted to be the gold standard of treatment. Traditional surgical excision with a scalpel has been used, but it is a time consuming procedure allowing only a small number of neurofibromas to be excised. In addition, radiofrequency excision or ablation causes less scarring than traditional surgical excision ().
Scar comparing with surgical and radiofrequency excision
Because the size of cutaneous neurofibromas varies from millimeters to centimeters, laser therapy has been used, but it was only useful in removing superficial neurofibromas and caused complications such as hypertrophic scars. Additionally, electro-surgical excision was introduced for the treatment of multiple cutaneous neurofibromas, which was a time sparing process and presented with lower frequencies of intra- and postoperative bleeding but the thermal necrotizing zone of normal tissue was a challenging problem.
Radiofrequency waves as applied in medicine cause thermal ablation of a defined volume of tissue [8
]. The RF ablation electrode acts as the cathode of an electrical circuit, which is closed by the application of dispersing pads on the patient's thighs [7
]. Because of the small cross-sectional area of the electrode tip, there is a very high energy flux around it. As a result, tissue damage is limited to the part of the circuit that surrounds the electrode tip. However, some disadvantages have been reported, such as skin pad burns and operator-dependent technique. These disadvantages can be overcome with careful monitoring of the skin pad site and coaching by senior operators.
Therefore, instead of time consuming traditional surgery with a scalpel, which produces uncertain results or affects normal adjacent tissue, treatment of neurofibromas with radiofrequency ablation and excision can be considered the best choice of treatment for patients with a large number of neurofibromas because of its effectiveness and time saving characteristics.
The critical factor of the surgical procedure is the depth of delamination. The removal of tissue below the depth of the pilosebaceous unit will result in a smooth atrophic scar. Furthermore, an uncertain depth of ablation will result in the recurrence of cutaneous neurofibroma. However, it is not easy to ensure the ablation depth during surgery because hundreds of cutaneous neurofibromas are handled in one operation. Some neurofibroma remnants can exist after incomplete ablation while ablation too deeply can result in smooth atrophic scars. For this reason, careful attention is required for every single ablation or excision.
Despite the need for particular conditions for the best outcome, radiofrequency ablation or excision is easy to learn and relatively simple to perform, requires minimal postoperative care, and provides a satisfactory cosmetic outcome with virtually no complications. The only disadvantage is the high price of the instrument.
This study has the limitation of comparison between traditional excision surgery and radiofrequency ablation due to the lack of pathologic studies. Furthermore, it is uncertain whether radiofrequency ablation can remove cutaneous neurofibromas entirely with a single treatment. The pathologic findings of cutaneous neurofibroma lesions ablated by a radiofrequency unit should be helpful in proving the superiority of radiofrequency ablation.
The most common and characteristic findings of Von Recklinghausen disease or NF 1 are multiple and recurrent cutaneous neurofibromas associated with psychosocial distress. It is a challenge for plastic surgeons to remove as many as thousands of cutaneous neurofibromas with acceptable scars within a limited operation time [13
]. The RF technique should be the treatment of choice for ablation and excision of cutaneous neurofibromas since it is almost bloodless and quick, creating a smaller necrotizing zone. RF ablation is likely to remain the mainstay of ablation therapy for a large number of cutaneous neurofibromas until sufficient experience emerges for the widespread acceptance of alternative ablative modalities.