Confirm Cancer-Associated LEMS with a VGCC-Ab test, both P/Q and N types

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Signs of Cancer-Associated LEMS:

Boulder with exclamation point carved into the side
Line drawing of person with crooked lines emanating outward from midsection, indicating the classic triad of signs of cancer-associated LEMS

Include the classic triad of proximal muscle weakness, autonomic dysfunction, and hyporeflexia or areflexia2,15

  • Proximal leg muscle weakness
  • Proximal arm muscle weakness
  • Dry mouth
  • Impotence
  • Constipation
  • Areflexia
  • Orthostatic hypotension
Line drawing a wheelchair, indicating worsening weakness and loss of mobility

Are progressive, leading to worsening weakness and the loss of mobility2,16

Line drawing of a cancer cell

May be mistaken for cancer or the side effects of cancer treatment4,16

>
90
%
UNDIAGNOSED
More than 90 percent of LEMS cases associated with SCLC may be undiagnosed

Estimated prevalence of patients with co‑occurring SCLC and LEMS (US patients 2014-2022)17

An analysis of claims data suggests that > 90% of LEMS cases associated with SCLC may be undiagnosed17

Review this poster presentation

LEMS presents with symptoms SCLC patients commonly experience, such as fatigue, weakness, and restricted mobility4,16

  • It is difficult to clinically differentiate these SCLC symptoms from LEMS—a VGCC-Ab test can help confirm the diagnosis3,12,18
  • SCLC patients with suspected LEMS pattern of weakness (either on chemotherapy or not) may benefit from VGCC-Ab testing3,12,13

If symptoms of weakness are caused by LEMS, an FDA-approved therapy is available.5

Patients with SCLC and Cancer-Associated LEMS exhibit more favorable survival rates than those with non-LEMS SCLC, with a median overall survival of 17 months compared to 7 months (P < 0.0001)10

Median Overall Survival Rate10

( P < 0.0001) 17 MONTHS CANCER-ASSOCIATED LEMS SCLC 7 MONTHS NON-LEMS SCLC NON-LEMS SCLC CANCER-ASSOCIATED LEMS SCLC 7 MONTHS 17 MONTHS ( P < 0.0001)

Testing for Cancer-Associated LEMS

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References:

  1. Gandhi L, Johnson BE. Paraneoplastic syndromes associated with small cell lung cancer. J Natl Compr Canc Netw. 2006;4(6):631-638.
  2. Titulaer MJ, Lang B, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies. Lancet Neurol. 2011;10(12):1098-1107.
  3. Gilhus NE. Lambert-Eaton myasthenic syndrome; pathogenesis, diagnosis, and therapy. Autoimmune Dis. 2011;2011:973808.
  4. Bebb DG, Murray C, Giannopoulou A, Felip E. Symptoms and experiences with small cell lung cancer: a mixed methods study of patients and caregivers. Pulm Ther. 2023;9:435-450.
  5. Yoon CH, Owusu-Guha J, Smith A, Buschur P. Amifampridine for the management of Lambert-Eaton myasthenic syndrome: a new take on an old drug. Ann Pharmacother. 2020;54(1):56-63.
  6. Wirtz PW, Smallegange TM, Wintzen AR, Verschuuren JJ. Differences in clinical features between the Lambert-Eaton myasthenic syndrome with and without cancer: an analysis of 227 published cases. Clin Neurol Neurosurg. 2002;104(4):359-363.
  7. Hartmann GG, Sage J. Small-cell lung cancer neuronal features and their implications for tumor progression, metastases, and therapy. Mol Cancer Res. 2024;22(9):787-795.
  8. Maddison P, Gozzard P, Grainge MJ, Lang B. Long-term survival in paraneoplastic Lambert-Eaton myasthenic syndrome. Neurology. 2017;88:1-6.
  9. Titulaer MJ, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: tumor versus nontumor forms. Ann N Y Acad Sci. 2008;1132:129-34.
  10. Lipka AF, Boldingh MI, van Zwet EW, et al. Long-term follow-up, quality of life, and survival of patients with Lambert-Eaton myasthenic syndrome. Neurology. 2020;94(5):e511-e520.
  11. ARUP Laboratories. Accessed August 2, 2025. https://ltd.aruplab.com/Tests/Pub/3002046
  12. Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Small Cell Lung Cancer V.2.2026. © National Comprehensive Cancer Network, Inc. 2025. All rights reserved. Accessed September 26, 2025. To view the most recent and complete version of the guideline, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use or application and disclaims any responsibility for their application or use in any way.
  13. Kunii E, Owaki S, Yamada K, et al. Lambert-Eaton myasthenic syndrome caused by atezolizumab in a patient with small-cell lung cancer. Intern Med. 2022;61:1739-1742.
  14. Giannoccaro MP, Avoni P, Liguori R. Presynaptic paraneoplastic disorders of the neuromuscular junction: an update. Brain Sci. 2021;11(8):1035.
  15. Titulaer MJ, Lang B, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies. Lancet Neurol. 2011; Appendix:1-4.
  16. Harms L, Sieb JP, Williams AE, et al. Long-term disease history, clinical symptoms, health status, and healthcare utilization in patients suffering from Lambert Eaton myasthenic syndrome: results of a patient interview survey in Germany. J Med Econ. 2012;15(3):521-530.
  17. Morrell D, Drapkin B, Shechter G, Grebla R. Lambert-Eaton myasthenic syndrome is underrecognized in small cell lung cancer: an analysis of real-world data. Presented as a poster at the International Association for the Study of Lung Cancer (IASLC) – WCLC Annual Meeting 2023. September 9-12, 2023, Singapore.
  18. Sanders DB. Lambert-Eaton myasthenic syndrome: diagnosis and treatment. Ann N Y Acad Sci. 2003;998:500-508.
  19. Catterall WA. Voltage-gated calcium channels. Cold Spring Harb Perspect Biol. 2011;3:a003947.
  20. Schampel A, Kuerten S. Danger: High voltage—the role of voltage-gated calcium channels in central nervous system pathology. Cells. 2017;6(4):43.
  21. Loser V, Vicino A, Théaudin M. Autoantibodies in neuromuscular disorders: a review of their utility in clinical practice. Front Neurol. 2024;15:1495205.
  22. Alhammad RM, Alshamian Y, Alneseyan R, Al-Harbi TM, Ajhijab A, Alanazy MH. Clinical presentations, electrophysiologic features, and long-term follow-up in Lambert-Eaton myasthenic syndrome: a series of six patients. Front Neurol. 2024;15:1525155.
  23. Labcorp. Voltage-gated calcium channel antibody (VGCCA). Accessed August 16, 2025. https://www.labcorp.com/tests/140640/voltage-gated-calcium-channel-antibody-vgcca
  24. Kesner VG, Shin JO, Dimachkie MM, Barohn RJ. Lambert-Eaton myasthenic syndrome. Neurol Clin. 2018;36(2):379-394.
  25. Silva T. Understanding lambert-eaton myasthenic syndrome: pathophysiology, diagnosis, and treatment. J Neurol Neurorehab Res. 2024;9(1):1-2.
  26. Ivanovski T, Miralles F. Lambert-Eaton myasthenic syndrome: early diagnosis is key. Degener Neurol Neuromuscul Dis. 2019;13:27-37.

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