NCCN Guidelines and Management of CA-LEMS in the Practice

This segment reviews how recent NCCN guideline updates influence oncologic practice in evaluating suspected cancer-associated Lambert-Eaton myasthenic syndrome (LEMS). Expert faculty explains that the guidelines now recommend symptom checklists and comprehensive voltage-gated calcium channel (VGCC) antibody testing—including both P/Q-type and N-type antibodies—to maximize diagnostic yield. They compare this approach to modern oncology’s reliance on broad DNA and RNA next-generation sequencing: incomplete testing increases the risk of missing clinically relevant findings. Despite these updates, they note that awareness among oncologists remains a barrier, as clinicians often rely less on guideline documents the longer they practice. The panel emphasizes the importance of early neurology referral, given that 10–15% of patients test seronegative and require expert evaluation. The discussion highlights the need for stronger outpatient neurology networks, the value of multidisciplinary collaboration, and recognition that patients with LEMS often present earlier and experience better prognoses than typical small cell lung cancer populations—reinforcing the importance of early identification and guideline-aligned care.