This is an extremely rare report of SCLC with VGCC antibody-positive PLE. A recent report had documented that antibodies to VGCC and Hu were found in 5% and 25.5%, respectively, of patients with SCLC without neurological disease (n=200), but their presence did not correlate with the extent of disease or outcome [
4]. VGCC antibodies had been described to be recognized in 41% of patients with paraneoplastic cerebellar degeneration and SCLC [
5]. However, patients with SCLC who have PLE have been rarely reported in the English literature, moreover, only four patients yielded a positive finding of VGCC antibody including our present case [
6‐
8]. Although the reason for the preferential association of PLE with SCLC is unclear, several researchers hypothesize a mechanism whereby the tumor expression of brain proteins is the trigger of autoimmunity against the nervous system [
1]. Patients who are anti-Hu-positive usually have multifocal neurological symptoms and SCLC is frequently associated with anti-Hu antibody. It has been reported that patients who are anti-Hu-negative with SCLC and limbic encephalitis are more likely to improve with treatment [
2]. Our patient also has a negative anti-Hu antibody; therefore, his neurological symptoms may improve after systemic chemotherapy. Furthermore, recent reports had documented that some neurological symptoms were improved after systemic treatment in patients with SCLC with VGCC antibody-positive PLE [
1,
6‐
8]. However, it remains unknown whether the presence of VGCC antibody is correlated with a good response to therapy.
In the present series, a brain MRI is helpful for excluding other diseases with similar neurological disorders. It has been described that the brain MRI of patients with PLE shows a typical finding of high signal intensity on flair or T2-weighted imaging in bilateral or unilateral medial temporal lobes and/or brain stem [
9,
10]. Cerebrospinal fluid tapping is also necessary to exclude evidence of malignant cells or infection; this corresponds to the results of our present case. However, it is difficult for oncologists to diagnose PLE with lung cancer as an initial presentation.