Background:Neurofibromatosis type 1 affects quality of life (QoL) through association with severe complications, impact on cosmetic features, and uncertainty of the effects of the disorder.Objective: To evaluate the impact of the severity and visibility of neurofibromatosis type 1 on QoL.

The observation that malignant peripheral nerve sheath tumors are strongly associated with internal plexiform neurofibromas suggests that patients with neurofibromatosis type 1 with these benign tumors warrant increased surveillance for malignancy.

Neurofibromatosis type 1 (NF1) is a genetic disease with a wide range of neurological manifestations. To examine these, and to evaluate neurological morbidity in adulthood of patients with NF1, we studied a hospital-based series of 158 patients that included 138 adult patients aged >18 years and 20 children. NF1 evaluation included a multidisciplinary clinical and a clinically oriented radiological investigation. Neurological events occurring during childhood (in both children and adults of the series) and adulthood were recorded. One or several neurological manifestations have been observed in 55% of patients (adults and children) (n = 87). These included: headache (28 patients); hydrocephalus (7); epilepsy (5); lacunar stroke (1); white matter disease (1); intraspinal neurofibroma (3); facial palsy (1); radiculopathy (5); and polyneuropathy (2). Tumours included: optic pathway tumours (20); meningioma (2); cerebral glioma (3); and malignant peripheral nerve sheath tumours (6). Life-threatening complications were observed in five adults and included four malignant peripheral nerve sheath tumours and one meningioma. Pain was the leading symptom in 11 adults and was related to malignant peripheral nerve sheath tumours, complications of intraspinal neurofibromas, subcutaneous neurofibromas and peripheral nerve neurofibromas. NF1 in adults was not associated with other disabling or life-threatening neurological complications. Symptomatic optic pathway tumours, cerebral gliomas, symptomatic aqueductal stenosis and spinal compression due to intraspinal NF were observed exclusively during childhood. In this series, the predominant neurological features of adults with NF1 were chronic pain and malignant peripheral nerve sheath tumours.

From a practical point of view, pain, neurological deficit and enlargement of a pre-existing peripheral nerve sheath tumour in NF1 must lead to deep surgical biopsy to rule out malignant transformation.

Neurofibromatosis 1 (NF1) is a genetically transmitted disease occurring approximately once in 3000 live births and resulting from mutations of the NF1 gene that encodes a protein named neurofibromin, a negative regulator of the ras-dependent pathway. An excess of neoplasia especially tumours of neuroectodermal origin is classically observed. The occurrence of malignant melanoma in patients with NF1 has already been described in scattered clinical reports but little is known as to the characteristics of melanoma arising in NF1 patients. A multicentric retrospective study was conducted on a panel of French referring centres for a period of 13 years to identify patients with both melanoma and NF1. Patients with mucosal or ocular melanoma were excluded. The diagnosis of malignant melanoma was based on specific histology whereas NF1 was identified according to the criteria proposed by the NIH Consensus Conference. All patient fulfilling criteria for both melanoma and NF1 were investigated using a common procedure recording clinical and histological data along with prognostic factors for the two diseases. Eleven patients were identified with both diseases. The clinical pattern of NF1 was quite similar to the classical form of the disease, but some unusual features were present as regards to the melanoma: a sex-ratio of 10 women for one man and an average age lower than expected (median age=33 years) for melanoma occurrence. Among prognostic factors, median thickness was high compared to large series of melanoma in the literature (3.20 versus 1.5 mm). Another neoplasia occurred in three patients. An increase in melanoma incidence in patients with NF1 remains hypothetical but our small series of malignant melanoma arising in NF1 patients displays a large female preponderance, a higher thickness than expected and a frequent association with a second neoplasia. The peculiar female proneness for cancer whatever its localization and the risk of multiple neoplasias have already been reported in NF1 patients and could be true for malignant melanoma as well.