Amyotrophic lateral sclerosis mimic syndrome due to a dorsal spinal cord neurofibroma

Actually amyotrophic lateral sclerosis (ALS) presentation is highly variable, in term of site and rate of progression and it is often subtle. The lack of a specific biological marker and the several differential diagnoses (the so-called ALS mimic syndromes) contributes to a frequent delayed diagnosis. We report a case of neurofibroma of the dorsal spinal cord with a presentation mimicking ALS. A 57-year-old man presented with a progressive muscle wasting and weakness at both legs. A diagnosis of possible ALS was considered but, after multiple examinations, the patient performed a MRI dorsal scan, which showed a large space-occupying lesion at the D10 to D12 level, extradurally pressing the spinal cord. The patient underwent an intervention for the exeresis of the lesion followed by stabilization of the column with peduncolar screws and bars. The pathological diagnosis was neurofibroma. The clinical follow-up showed an improvement of the lower limb strength. This case emphasizes the importance of a continuous review of the diagnosis of all cases with suspected or possible ALS and an atypical course.