RESUMO
Anti-Hu syndrome is a paraneoplastic neurological syndrome, most frequently associated with small cell carcinoma of the lung. Subacute sensory neuronopathy is thought to be the most frequent presentation of the anti-Hu syndrome, but it seems that sensory-motor neuropathy is the most common form in the anti-Hu neuropathy. Neurological symptoms often appear before the associated cancer has been identified. Sometimes the tumor is discovered months or even a few years after the appearance of the neurological syndrome. FDG-PET scan seems a better method for finding the tumor in patients with paraneoplastic neurological syndrome and anti-Hu antibodies who had negative test results after an initial workup using radiological methods. In this case report we present a patient with the anti-Hu syndrome associated with an unclassified rhabdomyosarcoma with epitheloid cellular morphology and neuroendocrine differentiation.