Differential Diagnosis of CA-LEMS and Improving Its Early Recognition

In this segment, expert faculty discuss one of the most challenging aspects of clinical practice: distinguishing chemotherapy-related fatigue from the neuromuscular weakness of cancer-associated Lambert-Eaton myasthenic syndrome (LEMS). They note that autonomic symptoms may help raise suspicion, but emphasize the need for objective tools and neurology involvement. The panel explains widely adopted LEMS-specific screening instruments are lacking, and oncology practices could benefit from incorporating neurology-oriented questionnaires, particularly for patients with newly diagnosed small cell or other neuroendocrine tumors, as well as those receiving immune checkpoint inhibitors. The discussion then shifts to underdiagnosis, which they attribute to the overlooked nature of early symptoms. The panel stresses the importance of longitudinal assessment, identifying worsening weakness, and initiating early neurology referral. They note prompt evaluation can accelerate diagnostic accuracy, facilitate appropriate t