We describe three patients with known or suspected small-cell lung cancer (SCLC), paraneoplastic neurological syndromes, and antineuronal antibodies who had unusually benign clinical courses. One patient survived 8 years free of disease and was positive for the anti-Hu antibody. A second patient survived 6 years after spontaneous tumour regression and had an atypical antineuronal antibody. A third patient with both the anti-Hu and atypical antineuronal antibody had spontaneous regression of a lung mass. All three patients had a subacute sensory neuropathy. Since paraneoplastic antineuronal antibodies also bind to tumour cells, these cases suggest that some (paraneoplastic) neurological syndromes without identifiable tumour may result from immune-mediated eradication of tumour cells.