Prognostic signs in the surgical management of plexiform neurofibroma: the Children's Hospital of Philadelphia experience, 1974-1994.

OBJECTIVES: To estimate the rate of progression of plexiform neurofibroma after surgery and to identify prognostic factors that predict progression. STUDY DESIGN: A retrospective review of the inpatient and outpatient records of 121 patients, who had 302 procedures on 168 tumors over a 20-year period at a single large pediatric referral center. Data on age, location, indication for surgery, and extent of resection was analyzed for prognostic significance. RESULTS: The overall freedom from progression was 54%. Children < 10 years old had a shorter interval of tumor control than older children (p = 0.0004). Tumors of the head/neck/face fared worse than tumors of the extremities (p = 0.0003). Less extensive resection predicted shorter interval to progression (p < 0.0001). Indication for surgery was not of prognostic importance. In multivariable analysis older age and location in the extremities were predictors of a better outcome. CONCLUSIONS: Tumor progression is a serious problem for children with plexiform neurofibroma. Younger children, children with tumors of the head/neck/face, and tumors that cannot be nearly completely removed are at particular risk. These data may be useful in helping clinicians decide which patients and which tumors are most likely to benefit from surgical intervention.

Neurofibromatosis type 1: brain stem tumours.

We describe the clinical and imaging findings of brain stem tumours in patients with neurofibromatosis type 1 (NF1). The NF1 patients imaged between January 1984 and January 1996 were reviewed and 25 patients were identified with a brain stem tumour. Clinical, radiographical and pathological results were obtained by review of records and images. Brain stem tumour identification occurred much later than the clinical diagnosis of NF1. Medullary enlargement was most frequent (68%), followed by pontine (52%) and midbrain enlargement (44%). Patients were further subdivided into those with diffuse (12 patients) and those with focal (13 patients) tumours. Treatment for hydrocephalus was required in 67% of the first group and only 15% of the second group. Surgery was performed in four patients and revealed fibrillary astrocytomas, one of which progressed to an anaplastic astrocytoma. In 40% of patients both brain stem and optic pathway tumours were present. The biological behaviour of brain stem tumours in NF1 is unknown. Diffuse tumours in the patients with NF1 appear to have a much more favourable prognosis than patients with similar tumours without neurofibromatosis type 1.

Brainstem tumors in patients with neurofibromatosis type 1: a distinct clinical entity.

The natural history and the clinical and neuroimaging features of brainstem tumors in neurofibromatosis type 1 (NF1) are poorly understood. Magnetic resonance imaging (MRI) has been useful in NF1 in detecting intracranial abnormalities, especially of the brainstem. Brainstem tumors in NF1 have been confused clinically with non-NF1 brainstem tumors and radiographically with the increased T2 signal abnormalities, also known as "unidentified bright objects" (UBOs), which are common in NF1 and often located in the brainstem. This study, which evaluated 17 NF1 patients with brainstem tumors, is the largest series to date. Fifteen of 17 patients (88%) had neurologic signs and symptoms referable to brainstem dysfunction, including dysarthria, cranial neuropathies, and gross motor incoordination. Tumors were located primarily in the medulla in 14 of 17 NF1 patients (82%), in contrast to the pontine tumor location in the non-NF1 population. Seven NF1 patients (41%) required shunt placement for hydrocephalus at initial diagnosis, more frequent than in non-NF1 brainstem tumor patients. Six of 17 patients (35%) had evidence of radiographic tumor progression, but only three of them (18%) had correlative clinical progression. Two patients with progressive symptoms had partial surgical resection, and pathology revealed either fibrillary or anaplastic astrocytomas. Three patients were treated with radiation therapy, chemotherapy, or both, with two deaths. With a median follow-up of 52 months, 15 of 17 patients remain alive; 14 of them did not require adjuvant therapy. In our series, we describe NF1 brainstem tumors as a distinct clinical entity, much less aggressive than non-NF1 pontine tumors but more symptomatic than brainstem UBOs in NF1.