A retrospective examine confirmed that Lambert-Eaton myasthenic syndrome (LEMS) related to small cell lung most cancers (SCLC) could also be underdiagnosed in real-world remedy settings, in accordance with findings printed in Frontiers in Oncology.1
What did the retrospective examine present about LEMS in SCLC?
Of 867,170 sufferers with eligible lung most cancers claims from 2017 to 2022, 46,995 (5.4%) who had been presumed to have SCLC had claims for remedy containing etoposide and platinum. Of this inhabitants, 77 (0.16%; 95% CI, 0.13%-0.20%) had a declare for LEMS through the examine interval, and of 8513 sufferers with presumed SCLC and at the least 12 months of follow-up, 16 (0.19%; 95% CI, 0.10%-0.28%) had a LEMS declare.
Amongst 76 sufferers with SCLC and LEMS diagnoses within the main inhabitants and at the least 12 months of claims historical past, the median time between diagnoses was 37 days (IQR, 1-155), and 19 (25%) had LEMS claims previous lung most cancers claims, most of whom (84%) had a lung most cancers prognosis inside 90 days. When evaluating the incidence of LEMS earlier than and after the standardization of immune checkpoint inhibitor use in SCLC care based mostly on a cutoff of March 2019, the prevalence charges had been 0.15% and 0.18%, respectively (P = .49).
“As a result of diagnostic challenges lengthen the time to LEMS prognosis in each tumor- and non-tumor LEMS [populations], it turns into clear that LEMS diagnoses could also be missed altogether. Certainly, fewer than half of sufferers with out there data in our examine had been recognized with LEMS by a neurologist. When LEMS diagnoses adopted SCLC diagnoses, the prognosis was even much less prone to be made by a neurologist relative to LEMS diagnoses previous SCLC prognosis, reflecting the alternatives for oncologists to acknowledge and make sure the situation,” Benjamin Drapkin, MD, PhD, an assistant professor within the Division of Inside Medication at UT Southwestern Medical Middle, wrote with coauthors within the publication.1 “[I]n a big, consultant, and up to date real-world inhabitants, over 90% of SCLC-associated LEMS circumstances seem to go undetected. This marked underdiagnosis happens regardless of availability of efficient LEMS remedy that may enhance sufferers’ high quality of life.”
What’s LEMS, and the way is it associated to SCLC?
The examine investigators described LEMS as an autoimmune neurologic dysfunction and a paraneoplastic complication of SCLC. Scientific hallmarks of LEMS embrace proximal muscle weak spot, autonomic dysfunction, and areflexia, which can be misattributed to most cancers or cancer-directed remedy, or go undetected solely. The refined presentation of LEMS within the confounding presence of SCLC, the authors famous, could heighten the danger of missed or delayed prognosis.
How was the real-world LEMS examine designed?
Investigators performed a retrospective evaluation of patient-level knowledge collected from Symphony Well being’s PatientSource database, which included medical and pharmacy well being care claims for greater than 300 million people within the US. Extracts for oncology had been restricted to October 2017 to April 2022, and LEMS knowledge had been restricted to March 2014 to July 2022 for the evaluation. Investigators collected data on affected person age, intercourse, insurance coverage kind, and geographic space.
The first final result concerned figuring out LEMS claims amongst sufferers with lung most cancers claims between 2017 and 2022 who additionally acquired etoposide plus platinum-based chemotherapy. Sensitivity analyses had been additionally performed by modifying the claims-based method to incorporate LEMS diagnoses based mostly on a single LEMS declare and at the least 3 LEMS claims spanning for 90 days or longer.
Throughout the first pattern, in circumstances with out LEMS (n = 46,918) and with LEMS (n = 77), the imply age was 66.3 years and 64.5 years, respectively. Most sufferers in every inhabitants had business insurance coverage (52.0% vs 62.3%) and resided within the South (44.8% vs 42.9%). Of word, sufferers with LEMS and lung most cancers (n = 390) had been considerably older (imply, 65.7 years) than these with LEMS with out lung most cancers (n = 1446; imply, 58.7 years; P <.001).
In August 2025, the
References
- Drapkin BJ, Morrell DJ, Grebla R, Shechter G, Gerber DE. Marked under-diagnosis of Lambert-Eaton myasthenic syndrome in small cell lung most cancers: an evaluation of real-world claims knowledge. Entrance Oncol. Entrance Oncol. 2025;15:1650373. doi:10.3389/fonc.2025.1650373
- Lambert Eaton myasthenic syndrome (LEMS) antibody testing and remedy suggestions added to NCCN Scientific Follow Pointers for small cell lung most cancers (SCLC). Information launch. Catalyst Prescription drugs. August 6, 2025. Accessed August 31, 2026. https://tinyurl.com/y35jr9ww
- NCCN. Scientific Follow Pointers in Oncology. Small cell lung most cancers, model 1.2026. Accessed August 31, 2026. https://tinyurl.com/yfxv8b5b
