Background
- Paraneoplastic syndrome of weakness that is associated primarily with small cell lung cancer, other solid cancers, or lymphoproliferative diseases
- Can be non-paraneoplastic (primary autoimmune)
- Pathophysiology is decreased acetylcholine release from the presynaptic nerves
Clinical Manifestations
- Slowly progressive proximal muscle weakness without significant atrophy
- Legs often more than arms
- Recovery of lost DTRs with exercise or muscle activation (postexercise/postactivation facilitation)
- Autonomic dysfunction can include dry mouth, slow pupillary light reflex, and erectile dysfunction
- Can affect cranial nerves
- Can cause respiratory failure late in the course
