Lymphangioleiomyomatosis (LAM)

The UT Southwestern Medical Center Lymphangioleiomyomatosis (LAM) Clinic is one of 33 LAM Foundation clinical sites in the nation and one of only two in Texas. Since its designation in September 2010, the UTSW LAM clinic has provided patients an array of diagnostic and therapeutic services from a diverse team of specialists. 

Specialized Treatment for Lymphangioleiomyomatosis (LAM)

Lymphangioleiomyomatosis (LAM) is a rare, progressive lung disease that affects primarily women, usually ages 20-40 and during their childbearing years. More than 2,000 U.S. women have been diagnosed with LAM, although population analysis suggests approximately 250,000 women worldwide might have the disease undiagnosed. 

LAM is caused by an abnormal growth of smooth muscle-like cells (LAM cells) blocking bronchial tubes and lymphatics, which includes the body’s 600 lymph glands (nodes), the liver, and the spleen. The growth leads to development of destructive lung cysts and progressive airflow obstruction. Other organs may be involved with fluid buildup in the chest cavity around the lungs (chylous pleural effusion) or abdominal fluid accumulation; fatty kidney tumors called angiomyolipomas; lymphangioleiomyomas (benign muscle and lymphatic-like tumors); and lymphangiomas (sacs filled with lymph fluid) in the chest and abdomen.

UT Southwestern Medical Center’s LAM Clinic has been recognized by the LAM Foundation as meeting the criteria for accurate diagnosis and treatment of the disease, as well as managing its many complications. The LAM team consists of pulmonologists, radiologists, and pathologists with expertise in LAM diagnosis; interventional radiologists with expertise in kidney tumor embolization; and cardiothoracic surgeons specializing in performance of pleurodesis (procedure for pleural effusion) and lung transplantation. These specialists are supported by respiratory therapists, nutritionists, and physical therapists who provide a full range of services to our patients.

Causes of LAM

The exact causes of LAM are unknown but thought to be related to mutations (changes) in the TSC1 and TSC2 genes. One form of LAM is hereditary, meaning the gene mutation is passed from parent to child. Another form is sporadic and not hereditary, and the reason for the gene mutations within the organs and tissues is not known.

Symptoms of LAM

LAM causes symptoms that worsen over time and may worsen during pregnancy. Symptoms include:

• Shortness of breath, especially with exercise
• Chest pain
• Cough, sometimes with phlegm or blood
• Pleural effusion (fluid buildup in the chest cavity around the lungs)
• Pneumothorax (collapsed lung), which can have symptoms such as sharp chest pain, severe difficulty breathing, rapid heartbeat, dizziness, and low blood pressure
• Wheezing

Diagnosing LAM

Symptoms of LAM can mimic those of bronchitis and asthma. The diagnosis is usually made when a computed tomography (CT) scan is performed to evaluate for unexplained shortness of breath, pleurisy, or a lung collapse (pneumothorax) and it reveals numerous lung cysts.

Our experienced pulmonologists carefully assess each patient for an accurate diagnosis. We begin with a thorough evaluation that includes a:

• Discussion of symptoms
• Review of personal and family medical history
• Physical exam

Patients often need one or more additional tests, such as:

• Blood tests: To measure the level of the hormone VEGF-D, which can indicate LAM
• Bronchoscopy: Minimally invasive procedure to view the airways using a thin, flexible tube with a tiny light and camera (bronchoscope) and to take mucus or tissue samples (biopsy) to examine under a microscope
• Chest X-ray: Images of the lungs to check for signs of disease
• Computed tomography (CT) scan: Imaging to look for lung cysts, using specialized X-ray technology that takes cross-sectional images to produce detailed 3D images
• Pulmonary function tests: Procedures to evaluate lung function, such as the rate of air flow in and out and how well the lungs move oxygen into the bloodstream
• Surgical biopsy: May be required for diagnosis by obtaining a lung tissue sample
• Ultrasound: Imaging that uses sound waves to produce images inside the abdomen to check for growths in the kidneys or lymph vessels

Treatment for LAM

The latest treatments to relieve symptoms and help prevent the condition from worsening include:

• Sirolimus (Rapamune®) or everolimus (Affinitor®): The only medications approved by the U.S. Food and Drug Administration (FDA) to treat LAM can improve lung function and shrink kidney tumors.
• Oxygen therapy: Supplemental oxygen can help with breathing.
• Bronchodilators: Inhaled medications help open airways and improve air flow for breathing.
• Minimally invasive or surgical procedures: We can remove fluid from the chest or remove or shrink angiomyolipomas.
• Pulmonary rehabilitation: We offer specialized rehab to help patients breathe better and improve their ability to exercise or do other activities.
• Lung transplant: People with severe cases of LAM can benefit from lung transplant as a last resort.

For more information about lymphangioleiomyomatosis, visit thelamfoundation.org. 

Clinical Trials

Our LAM Clinic is currently participating in the Multicenter International Durability and Safety of Sirolimus in Lymphangioleiomyomatosis Trial (MIDAS Trial). This study is an observational registry study hoping to enroll 300 LAM patients who are on, have previously taken, or are considering starting sirolimus or everolimus for treatment of LAM, with close follow-up of lung function tests and recording any adverse events for at least two years. This study will help refine treatment for patients with LAM and determine whether therapy with sirolimus or everolimus prevents progression of the disease.

For more information on clinical trials for Lymphangioleiomyomatosis, visit thelamfoundation.org.