Paraneoplastic syndromes associated with anti-Hu antibodies

Paraneoplastic syndromes are disorders associated with cancer but without a direct effect of the tumor mass or its metastases on the nervous system. S mall cell carcinoma of lung associated with paraneoplastic sensory neuronop athy and/or paraneoplastic encephalomyelitis with the presence of anti-Hu a ntibodies has been termed "anti-Hu syndrome." Anti-Hu associated PSN-PEM is an immune disorder in which both cell-mediated and humoral mechanisms are involved, Patients are considered affected by Anti-Hu associated PSN-PEM wh en they develop clinical signs and symptoms of CNS dysfunction and/or senso ry neuropathy not caused by metastases or other disorders, and serum or cer ebrospinal fluid is positive for Hu abs, SCLC is found in more than 90% of patients with cancer and positive Hu abs. Individual patients with Hu abs a ssociated to SCLC may suffer PSN-PEM, limbic encephalitis, brainstem enceph alopathy, opsoclonus-myoclonus, paraneoplastic cerebellar degeneration or m yelopathy. Hu abs have a specificity of 99% and sensitivity of 82% in detec ting paraneoplastic neurological syndromes. There are two types of treatmen t: the first is to treat the cancer, the second is to suppress the immune r eaction with the use of corticosteroids, cyclophosphamide, azathioprine, pl asma exchange, intravenous immunoglobulin and immunoadsorption; however, tr eatment of paraneoplastic syndromes is generally unsatisfactory.