A 57-year-old woman presented with subacute sensory, ataxic neuronopathy. Clinical investigation revealed a right-sided non-small-cell lung cancer. Serum investigation for specific antineuronal antibodies was negative. Histology showed T lymphocytic infiltrates in dorsal root ganglia. The observed histological pattern is similar to that described in antibody-positive cases. Thus, these findings suggest similar pathways in specific antineuronal antibody-negative and -positive cases of paraneoplastic subacute sensory neuronopathy.