Thoracic endometriosis syndrome (TES) is so rare that doctors have a hard time estimating how many lives it disrupts. One MyEndometriosisTeam member wrote, “Just because this type of endometriosis is not common does not mean your doctor should dismiss your symptoms or the possibility that you have thoracic endometriosis.”

Thoracic endometriosis can occur as a solitary condition, but it usually appears in people who have endometriosis in other parts of the body as well. Between 50 percent and 84 percent of people diagnosed with TES also have pelvic endometriosis.

It’s important to learn about thoracic endometriosis syndrome and its symptoms. If you notice any of these symptoms, talk with your doctor so you can make sure you receive the best care possible.

What Is Thoracic Endometriosis Syndrome?

The lining of your uterus is called the endometrium. During your menstrual cycle, it grows, swells, and bleeds with your period. When endometrial-like tissue grows outside your uterus, it is called endometriosis. This tissue that grows outside your uterine cavity can cause pain and symptoms because it can respond the same way as your endometrium to menstrual hormones. Endometriosis can happen anywhere in your body, but it tends to occur most frequently in the pelvis.

Thoracic endometriosis syndrome occurs when endometrial-like tissue grows in or around your lungs and diaphragm, and along the surfaces of your thoracic cavity. Your thoracic cavity is the space inside your ribs that holds your lungs, heart, and diaphragm — the muscle between your lungs and your stomach that helps you breathe.

There are four main signs of TES:

• Catamenial pneumothorax — A collapsed lung caused by air trapped in the chest cavity
• Catamenial hemothorax — A collapsed lung caused by blood in the chest cavity
• Catamenial hemoptysis — Coughing up blood
• Lung nodules — Bits of endometrial-like tissue in the lungs

“Catamenial” comes from the Greek word “katamenios,” meaning “monthly.” “Pneumothorax” is the medical term for what happens when your lung collapses. Gas or air can become trapped outside your lung in the chest cavity, preventing it from fully filling with air. Catamenial pneumothorax is the most common of these four TES signs.

A hemothorax happens when blood from the endometrial-like tissue builds up in your chest cavity, in between your lungs and ribs. This prevents your lungs from being able to fill completely. If your lungs fill with blood, you may cough up blood, called catamenial hemoptysis.

The spots of endometrial tissue sometimes found in the lung tissue of people with thoracic endometriosis are called lung nodules. TES with lung nodules is a very rare condition.

What Are the Symptoms of Thoracic Endometriosis?

The most commonly reported symptoms of thoracic endometriosis are:

• Shortness of breath
• Chest pain
• Coughing up blood
• Shoulder pain (usually on both sides, but it can be felt on just one side)
• Dyspnea (trouble breathing)
• A crackling sensation in the lower chest
• Dizziness or feeling tired

If your lung collapses, you may experience sudden, severe chest pain and shortness of breath. These symptoms can bring people with thoracic endometriosis to emergency rooms with each menstrual cycle.

Having fluid in your lungs or endometrial-like tissue in your diaphragm (diaphragmatic endometriosis) can cause referred pain. Referred pain radiates up your back to your shoulder blades and neck. Stomach ulcers and acid reflux can cause similar symptoms, so individuals with diaphragmatic endometriosis are often misdiagnosed.

The telltale clue for thoracic endometriosis syndrome is the connection in timing between menstruation and your symptoms. MyEndometriosisTeam members describe feeling “out of breath with most menstrual cycles, feeling like someone is sitting on my chest” and a “tightness in my chest, neck, and lungs whenever I have my period.” Other members report these symptoms can last up to a week and also happen when ovulating.

A catamenial pneumothorax usually happens within 72 hours of the start of your period. Even though they can recur, they don’t reliably happen with every menstrual cycle, which can make the cause hard to diagnose.

How Do Doctors Diagnose Thoracic Endometriosis?

If you have endometriosis in the pelvic area, explaining your symptoms can help doctors diagnose your endometriosis. Because thoracic endometriosis syndrome is a rare condition, doctors and emergency health care providers don’t jump to TES as their first diagnosis when someone has shortness of breath or chest pain. Instead, you may be examined for a heart attack, lung cancer, a blood-clotting disorder, or a lung infection. The diagnosis of thoracic endometriosis may be missed or delayed by months or years.

Doctors diagnose thoracic endometriosis when they find endometrial-like tissue in or on your lungs, diaphragm, or thoracic cavity. Very often, doctors diagnose thoracic endometriosis while treating a collapsed lung or other breathing problems related to your endometriosis.

Video-assisted thoracoscopic surgery (VATS) is the most common surgical procedure used to diagnose and treat thoracic endometriosis. Using a tiny camera inserted through small incisions in your chest wall, your surgeon can see, biopsy (take tissue samples), and remove endometrial tissue, adhesions, or excess fluid and blood.

Sometimes surgeons will also do procedures such as bronchoscopy or thoracoscopy. In bronchoscopy, a tube with a camera is inserted into your lungs through your mouth. In thoracoscopy, the tube enters through a small cut in your chest to look for the cause of your breathing difficulties or chest pain.

Doctors may use a combination of chest X-rays, computed tomography (CT) scans, and positive emission tomography (PET) scans to identify lung nodules. Unfortunately, TES lung nodules are often first misdiagnosed as benign or malignant pulmonary nodules, again delaying diagnosis of thoracic endometriosis.

How Do Doctors Treat Thoracic Endometriosis?

Because the symptoms caused by TES can be severe and painful, most people first get treated for their symptoms before addressing the underlying cause.

Most people with thoracic endometriosis also have pelvic endometriosis. The most effective treatment for thoracic endometriosis combines the surgical removal of endometrial tissue from your thoracic area and your pelvis. Ideally, surgeons do both surgeries simultaneously, so you only have to be under anesthesia once, and the recovery is easier.

The VATS procedure is the most common type of surgery for thoracic endometriosis, combined with laparoscopy to remove pelvic endometrial tissue. A combined surgical treatment plan, overseen by a thoracic surgeon and a gynecologist, is the most comprehensive and successful treatment option for thoracic endometriosis.

As one MyEndometriosisTeam member advised, “It's important to find an endometriosis specialist who treats thoracic endometriosis. Because it is so rare, not all endometriosis specialists or thoracic surgeons are trained in the surgery you need for treatment.”

Seeking care from a combination of experts in thoracic surgery and gynecology is especially important if you are experiencing infertility or planning a future pregnancy.

Doctors often follow surgical treatment with contraceptives or hormonal medications to prevent ovulation. These hormonal medications decrease the chances of symptoms recurring, although there currently is no cure for thoracic endometriosis.

Find Support and Information

It can be exhausting to navigate a health care system that does not know how best to treat you. One MyEndometriosisTeam member shared, “It helps to bring along articles or studies that reference thoracic endometriosis — that way your doctor is more likely to believe you.”

If you have the symptoms of thoracic endometriosis, especially if you also have pelvic endometriosis, talk to your doctor or gynecologist.

Talk With Others Who Understand

MyEndometriosisTeam is the social network for people with endometriosis and their loved ones. On MyEndometriosisTeam, more than 127,000 members come together to ask questions, give advice, and share their stories with others who understand life with endometriosis.

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