SCREENING SCLC Patients FOR LEMS

SCREENING SCLC PATIENTS FOR LEMS

3 WAYS TO CHECK FOR SYMPTOMS OF LEMS

2. Ask your patient if they are experiencing any of these hallmark signs and symptoms of LEMS⁴

3. Order confirmatory testing when LEMS is suspected

Confirm suspected LEMS cases with an anti-voltage-gated calcium channel (anti-VGCC) antibody test and/or electrodiagnostic testing⁷

UNCOVERING LEMS ASSOCIATED WITH SCLC

A case study review of Lambert-Eaton myasthenic syndrome (LEMS) in a patient with small cell lung cancer (SCLC)

DIAGNOSTIC WORKUP AND FRONTLINE TREATMENT

• Male, age 71, with a >50 packs/year tobacco history, 15-pound weight loss
• Diagnosed using PET with extensive-stage SCLC and metastatic liver disease
• Cycle 1 chemoimmunotherapy is initiated with carboplatin, etoposide, and atezolizumab

FOLLOW-UP COMPLAINT

• 3 weeks later, the patient is brought to the oncology clinic in a wheelchair; his family expresses concern that he spends most of his time in bed or on the couch
• Patient complains of dry mouth and loss of appetite
• Labs show mild leukopenia, no hyponatremia, and normal TSH
• Pegfilgrastim is added to the patient’s Cycle 2 regimen, and the clinical team discusses early follow-up CT scanning prior to the next visit

CLINIC VISIT PRIOR TO START OF CYCLE 3 CHEMOIMMUNOTHERAPY

• CT CAP shows mild interval reduction in primary lesion and liver metastases; the patient remains weak with declining ECOG performance status
• Patient has difficulty standing and walking
  • Unable to get up from wheelchair on first 3 tries; once up, patient walks with a wide-based gait and hasdifficulty getting on the exam table
• Physician has a high index of suspicion for a paraneoplastic syndrome and is concerned the patient may betoo weak to continue SCLC treatment
• Palliative care and neurology referrals are placed, but due to a 6-month scheduling backlog, a blood-based paraneoplastic panel is ordered immediately

LEMS IS DIAGNOSED

• Paraneoplastic panel is positive for voltage-gated calcium channel (VGCC) antibodies (245.7 pmol/L)
• Patient is admitted to a neurology clinic where EMG findings are found to be consistent with LEMS

LEMS TREATMENT INITIATED WITH AMIFAMPRIDINE

• Patient is started on amifampridine for treatment of LEMS symptoms
  • Amifampridine dose is titrated over the next few weeks to achieve optimal therapeutic dose and frequency
  • Amifampridine increases availability of ACh—a key neurotransmitter enabling communication between nerves and muscle in the neuromuscular junction4
• At the next clinic visit for Cycle 4 chemoimmunotherapy, the patient’s LEMS symptoms have improved
• Risk of exacerbating autoimmune conditions is discussed with patient and family, but with good symptom control, the patient opts to continue immunotherapy

WHY LEMS MONITORING IS IMPORTANT IN PATIENTS WITH SCLC

• LEMS is the most common antibody-mediated neurologic paraneoplastic syndrome associated with SCLC42
• Estimates suggest >90% of LEMS cases associated with SCLC may be undiagnosed⁴⁵

ACh=acetylcholine; CT=computed tomography; CT CAP=CT of the chest, abdomen, and pelvis; ECOG=Eastern Cooperative Oncology Group; IHC=immunohistochemistry; MRI=magnetic resonance imaging; TSH=thyroid-stimulating hormone; TTF1=transcription termination factor 1.