BCSE Practice Exam 2026 – Complete Study Resource

Lambert-Eaton myasthenic syndrome (LEMS) is a neuromuscular disorder often associated with small cell lung cancer (SCLC). In many cases, LEMS can present with muscle weakness that improves with repeated use, due to a defect in the neurotransmitter release at the neuromuscular junction. One significant aspect of LEMS is that it may be one of the earliest manifestations of an underlying malignancy, particularly SCLC.

In a clinical setting, the onset of symptoms like fatigue and muscle weakness can occur before the detection of the lung cancer itself. Recognition of this syndrome may prompt further investigation for malignancy, leading to an earlier diagnosis of SCLC. This makes the association between LEMS and SCLC particularly notable, as patients exhibiting symptoms of LEMS may be identified as having an underlying malignancy sooner than if the cancer had manifested through other means.

The other options do not accurately capture the established relationship between LEMS and SCLC. Muscle wasting and respiratory failure may occur in advanced disease but are not as directly linked as the onset of LEMS symptoms in relation to cancer diagnosis. Impaired cognitive function and memory loss are not typical features of LEMS, and while gastrointestinal disturbances can occur due to other side effects