Background: Twenty-four patients with neurologic involvement and anti-Hu antibodies were studied with the aim of defining the type of tumor associated, evaluating whether the clinico-pathologic picture agreed with the concept of paraneoplastic encephalomyelitis (PEM) and evaluating the treatments used.
Methods: The study was retrospective with the clinical histories being reviewed to define the neurologic syndromes, their evolution and response to the different treatments, time of appearance and type of tumor as well as the neuropathologic changes in the patients undergoing autopsy.
Results: In 18 patients a neoplasm was diagnosed as small cell pulmonary carcinoma (SCPC) in 89% of the cases. The neurologic picture preceded the tumor by an average of five months. The clinical pictures included: sensitive neuropathy (20 patients), cerebellous and truncus encephalicus involvement (8 patients), motor neuropathy (6 patients), cortical involvement (5 patients) and neurovegetative dysfunction (4 patients). In 55% of the patients more than one area was altered. Post mortem studies carried out on 5 patients demonstrated inflammatory infiltrates and neuronal loss in multiple areas of the nervous system. None of the patients improved with treatment. The 9 patients who only received immunodepressants evolved in a way similar to those who were not treated. In 7 of the 11 patients who received antitumoral therapy, the neurologic syndrome stabilized for at least 6 months.
Conclusions: The clinicopathological picture and the associated tumor seen in patients with anti-Hu antibodies are identical to those seen in PEM. Antitumoral treatment seems to be more effective than immunodepressant treatment.