Neuronal autoantibodies might play a role in the cognitive impairment that affects two-thirds of patients with lung cancer, German researchers say.

Neurologists, immunologists and lung cancer specialists teamed up for a study in which serum from 167 patients with lung cancer (mean age 66 years, 63% men, 55% stage IV disease) was examined for the presence of neuronal autoantibodies.

Forty patients had small cell lung cancer (SCLC) and 127 had non-small cell lung cancer (NSCLC), the study authors reported in JAMA Oncology.

More than a third (37%) had brain-directed autoantibodies in their blood, with 20% having recognised neuronal autoantibodies and the remainder having autoantibodies to brain tissue that had not been reported before, the authors said.