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Frequently Asked Questions
Frequently Asked Questions
LEMS is a rare neuromusculara system in the body that includes nerve cells called neurons and the muscles they control disease that can have a profound effect on a person’s mobility and quality of life.
People with LEMS may also experience dry mouth, weakness of the head and neck muscles, constipation, dizziness upon standing, dry eyes, and blurred vision. Men may experience impotence erectile dysfunction.
LEMS is an autoimmune diseasea disease caused by a malfunction
in the body’s defenses. In LEMS, the body overproduces a particular set of antibodiesproteins made by the immune system that fight infections that mistakenly attack and damage nerve cell endings. These attacks disrupt communication between the nerves and muscles, leading to muscle weakness.
LEMS is a rare condition. It is estimated to affect approximately 3,000 people in the US.
LEMS typically affects men and women between the ages of 35 and 60. Both men and women are equally at risk for LEMS not associated with cancer. Individuals with LEMS not associated with cancer are more susceptible to autoimmune disorders.
If you’ve already been to your primary care physician and are still searching for answers, you should ask to be referred to a neurologist or neuromuscular specialist. These are physicians who specialize in diseases of the nerves and muscles and will know what tests to administer to identify the cause of your symptoms.
To search for LEMS specialists in your area, use the LEMS Physician Locator.
There is currently no cure for LEMS, but there are therapies available for managing symptoms, including one treatment that is FDA-approved and proven clinically effective for the treatment of LEMS. Your neurologist or neuromuscular specialist will recommend the treatment that’s right for you.
Today’s recommended oral medications usually provide relief of LEMS symptoms within hours of taking the pill or prepared suspension. Treatment must be taken every day in order to maintain this positive response.
LEMS can be difficult to diagnose for several reasons: It is a rare disorder, symptoms may come and go in some patients, and there are other neuromuscular diseases that cause similar symptoms of muscle weakness. In fact, LEMS is most often initially diagnosed as myasthenia gravis (MG), a closely related neuromuscular disorder. LEMS is also mistaken for multiple sclerosis, amyotrophic lateral sclerosis, myopathy, and Guillain- Barré syndrome.
The good news is that LEMS can be accurately diagnosed based on the results of a physical examination and confirmatory testing with a blood test or a nerve stimulation test known as electromyography.
LEMS is caused by an overactive immune system. However, in about 50% of cases, the overactivity is related to cancer, often small cell lung cancer (SCLC).
Most cases of SCLC LEMS occur in people with a history of smoking.
Your neurologist will refer you to an oncologist for treatment of the cancer, usually chemotherapy. Treating the cancer may also help improve the symptoms of LEMS.
Achieving successful remission of the underlying cancer does not guarantee relief of your LEMS symptoms. If those symptoms do persist, it’s important to speak to your neurologist about starting (or continuing) therapy that will specifically address your LEMS symptoms.
Onset of LEMS symptoms is variable, ranging from 6 years prior to cancer diagnosis to 5 years after cancer diagnosis. In many cases, LEMS symptoms will appear a year or more before cancer is diagnosed, which can be a helpful early warning sign to the doctor that their LEMS patient should be screened for cancer. Download this helpful Doctor Discussion Guide.
Yes, 50% to 60% of LEMS patients will have a co-occurrence of cancer. All patients diagnosed with LEMS should be screened for cancer. Learn more about cancer screening here.
Approximately 1 in 10 patients with lung cancer will have a co-occurrence of LEMS. Antibody testing is recommended for all patients diagnosed with lung cancer who exhibit signs of neuromuscular disease. Learn more about LEMS antibody testing here.
While cancer treatment is always the first priority, treatment of LEMS symptoms is important for helping maintain muscle strength and functional mobility, which can help you maintain a positive outlook as you receive your cancer care.
Caregiver FAQs
No, LEMS is not contagious.
Currently, no direct genetic link has been identified for LEMS, but genetics may play a role in how likely a person is to develop an autoimmune disease.
Reasons to contact your LEMS patient’s physician may include:
- Noticing a worsening of symptoms or the development of new symptoms despite taking the prescribed medicine. Refer to the “Could It Be LEMS?” page for a complete list of LEMS symptoms
- Your loved one refuses to take their prescribed medication
- The development of adverse events or side effects that seem to be related to the patient’s prescribed medicine
- Your loved one is scheduled for surgery, dental work, or another medical procedure that will require anesthesia. Refer to “Considerations for When…” to learn more
Information on treatment options for LEMS is available on the “Testing and Treating” page. The following organizations also offer information about treatments and ongoing research in LEMS: