This is a multi-center observational study in subjects with a diagnosis of small cell lung cancer. Screening and/or medical record review for symptoms associated with Lambert Eaton Myasthenic Syndrome (LEMS) will be conducted.

This is a multi-center observational study in subjects with a diagnosis of small cell lung cancer. All eligible subjects enrolled will undergo a brief, symptom directed neurological evaluation and VGCC antibody testing (to be performed at a participating Quest laboratory). The results (positive/negative) of VGCC antibody testing will be documented as well as the receptor type P, Q or N.

These tests will be repeated quarterly (Q3 months) for the duration of the study.

If at any visit the subject is found to be BOTH neurologically suggestive of having LEMS and the VGCC Ab test is positive, then the subject is considered to be Clinically Suspicious of having LEMS. At any visit if a subject meets the criteria of Clinically Suspicious of LEMS. the end of study visit will be completed. Once the End of study visit is completed no further treatment information will be collected.

Inclusion Criteria:

1. Adult men or women meeting Age of Majority (AOM) at the time of consent
2. Provide voluntary consent to participate in this study, documented via a signed informed Consent Form (ICF)
3. Any diagnosis of SCLC
4. Willing to provide clinical and medical information related to his/her cancer diagnoses to the study team as required
5. Willing to comply with the requirements of the study

Exclusion Criteria:

1. Has been diagnosed with non-tumor Lamber-Eaton Myasthenic syndrome (LEMS) > 1 year prior to the SCLC diagnosis.
2. Known existence of an uncontrolled intercurrent illness including, but not limited to, psychiatric illness or social situations that would impair compliance with study requirements

United States