Endometriosis in the lungs
It is particularly common to find endometriosis tissue in the pelvis or on the ovaries. It is also possible, although rare, for endometriosis lesions to settle in the lungs.[1] This can be indicated by symptoms such as chest pain, shortness of breath, shortness of breath and cough.[2] But how does the unwanted tissue get into the lungs and what complications can this have? Today, we are clarifying these and other exciting questions together.
Thoracic Endometriosis Syndrome (TES)
Thoracic endometriosis is limited to the chest and what lies behind it. Physicians count this form of endometriosis as endometriosis extragenitalis. In this case, foci occur in various organs and tissues outside the uterus. Thus, the bladder, ureter or vagina can be affected. In rare cases, endometriosis lesions can also be found in the lungs. If the endometriosis-like tissue occurs in the pleura, diaphragm or lung parenchyma, physicians also refer to this as “thoracic endometriosis syndrome (TES)”. To explain: The lung parenchyma is tissue that is responsible for breathing.
Excursus: How the lungs work
Endometriosis in the lungs can have far-reaching consequences. To help you understand why diagnosis and treatment of endometriosis lesions in the lungs are so important, I would like to take a closer look at how the lungs work. As one of the most elementary organs, the lungs ensure that oxygen is absorbed from the air we breathe and transported through the body. This is important because energy production in the cells can only take place with sufficient oxygen. The sensitive organ, the lung, is hidden behind the ribs in the rib cage. The comparison with a tree is quite justified, because the trachea resembles a tree trunk. Two “branches”, the main bronchi, branch off from this trunk on both sides. In the two lungs, one on the left and one on the right of the trachea, the main bronchi branch out into smaller and smaller bronchi. At the end of the bronchial branches are the alveoli (alveoli).[1]
Respiration always proceeds in the same way:
- You breathe in, your chest expands.
- Oxygen-containing air passes from the trachea through the bronchi to the alveoli.
- The lining of the alveoli consists of fine blood vessels that transport oxygen into the bloodstream.
- Now the oxygen is “shipped” to every tiny cell and every corner of the body.
- You exhale as your lungs contract and the “used” air escapes.
Good to know
The alveoli are responsible not only for transporting oxygen into the blood, but also for reabsorbing carbon dioxide from the blood. The sophisticated mechanism is called gas exchange. Your body is supplied with sufficient oxygen only if everything runs smoothly in the lungs. Endometriosis lesions can disrupt the delicate balance in the lungs, leading to distressing symptoms.
Endometriosis in the lungs: symptoms
Breathing plays a major role in determining how efficient you are. Patients with lung disease can therefore be severely limited in their quality of life. Endometriosis in the lungs can also cause symptoms and complications that are distressing. Since endometriosis findings are quite rare in comparison, affected individuals do not immediately think of the corresponding lesions when symptoms become apparent.
The following symptoms occur with endometriosis in the lungs:
- Chest pain
- Pneumothorax (accumulation of air in the chest)
- Hemothorax (accumulation of blood in the chest)
- Hemoptysis (expectoration of bloody secretions)
- Pain that extends to the right shoulder
Special form of catamenial pneumothorax
A pneumothorax is characterized by air accumulating in the pleural space. The pleural space is located between the lung and the chest wall and is lined by a narrow layer of fluid. In addition, there is a slight negative pressure, so that the lung is firmly attached to the chest wall but can still be moved by the fluid when breathing. If air now enters the gap here, the lung is no longer held against the chest wall and collapses. Pneumothorax is therefore often referred to as lung collapse.
Among other things, the phenomenon can occur without an identifiable cause, as a result of medical intervention or an injury.[1] Catamenial pneumothorax is a special form associated with endometriosis. The associated complaints such as shortness of breath, pain in the chest and pulling into the shoulder are typical here. It is interesting that the complaints are temporally related to menstruation. Therefore, catamenial pneumothorax is also called menstrual pneumothorax. As a rule, the symptoms occur one to three days before menstruation. What is exciting in this context is what leads to the phenomenon in the first place.
There are two variants of how the air can get into the pleural space. From the lung itself, for example, if there are endometriosis lesions on the lung. Alternatively, there is also the phenomenon of air leaking from the uterus into the thoracic cavity. Air can enter the uterus through the vagina and through the fallopian tubes into the abdominal cavity even without endometriosis. However, if there is a defect in the diaphragm due to endometrial tissue of the diaphragm, this air enters the pleural cavity.[2][3]
Catamenial lung collapse is very rare in itself. Pneumothorax (lung collapse) is more common in young men than in women.
How common is a catamenial pneumothorax?
So it sounds like a real unicorn in the field of lung collapse, doesn’t it? Overall, yes, but when it comes to pulmonary collapse in a young woman, it’s something that should always be kept in mind, according to one study. If we take just those women who are of childbearing age and have pneumothorax, endometriosis is a common cause. In this group, the catamenial pneumothorax incidence was reported to be 7.3% to 36.7%. Admittedly, this is a wide range. However, it does underscore that menstrual pneumothorax is probably not as rare as perhaps thought. Incidentally, it has been observed that sufferers of catamenial pneumothorax were comparatively older than women with other types of endometriosis. In one scientific study, the average age was 35 years.10 Another study has provided even more exciting findings.[1]
- In 89 % of the cases, endometriosis was present at the diaphragm.
- In 93% of cases, the right half of the thorax was affected.
- In 55 % of the cases in which diaphragmatic endometriosis was present, endometriosis lesions were present in the pelvis.
- In 50% of the affected patients, the pelvic endometriosis lesions had been previously operated on.
Good to know!
You are probably wondering how endometriosis tissue manages to settle in the lungs. There are various theories for this. A widespread assumption is that the cells can spread through the peritoneum. However, this does not explain the presence of endometriosis in the lungs in patients who do not have corresponding tissue in the pelvis. Therefore, current studies neglect this theory. It is now being discussed whether endometriosis cells of a different nature may be taking over the lungs. However, more research is needed here.
Endometriosis in the lungs: examples from practice
Not many physicians get to see a patient with endometriosis in the lung. This makes it all the more important to share the evidence that is already available.
I would like to share with you some cases that have already been documented. This will give you an idea of how endometriosis in the lungs can present.
A practical example from Greece
A 29-year-old woman has been suffering for six months from complaints that occur on the third and fourth day during her period. During this period, the patient is always tormented by coughing attacks and bloody sputum. Examinations showed that the blood values were so far inconspicuous. Only an increase in a tumor marker (CA-125) was detected. Incidentally, tumor markers are substances that can be present in increased amounts in certain types of cancer. The patient also underwent imaging procedures such as X-ray, CT and MRI. During magnetic resonance imaging, the physicians detected a compression in the right lung, on the fourth day of menstruation. Subsequently, a laparoscopy was performed, during which the doctors discovered endometriosis – the fallopian tube was blocked. To treat the endometriosis, the patient was given GnRH agonists (leuprorelin). Such drugs are administered to achieve a lowering of estrogen levels. This can be crucial because the sex hormone estrogen supports endometriosis. By administering the drugs, the lung symptoms decreased, the patient became symptom-free and soon became pregnant. In a procedure performed by the doctors during the cesarean section, the foci were removed.[1]
A practical example from China
Here, a 29-year-old woman also presented to the doctor. She has chest pains and coughing fits at regular intervals. Mistakenly, the diagnosis of tuberculosis was initially considered and antibiotic therapy was prescribed. At first she felt better, but the symptoms returned. On her own authority, the patient discontinued her medication and sought advice from a lung expert. In a doctor-patient discussion, the woman stated that she only struggled with the symptoms once a month. This is an important clue. The woman had a computed tomography scan done, right when she was menstruating. The images showed that there was an inflammatory reaction and a nodule in the lung. With the help of a bronchoscopy, tissue was removed and examined in the laboratory. Thus, it was confirmed that the case was endometriosis in the lung. The endometriosis lesions were removed in a surgical procedure.[1]
How endometriosis is diagnosed in the lungs
The medical history, i.e. the conversation between doctor and patient, can provide decisive clues. If the symptoms occur mainly during the period, this may indicate endometriosis in the lungs. It is also interesting to know whether you have already been diagnosed with endometriosis and which treatment was chosen. To confirm the suspicion and to exclude other diseases, imaging techniques are useful. In particular, magnetic resonance therapy and computer tomography can help to visualize changes in the lungs. This may already reveal nodules or inflammatory changes in the form of shading. As in the practical example from China, a bronchoscopy can be performed to obtain tissue and examine it in the laboratory. Once the diagnosis is confirmed, this can be followed by targeted therapy.
How endometriosis in the lung is treated
In order for the symptoms to decrease and the risk of complications to be limited, therapy is necessary. The guideline program of the German Society for Gynecology and Obstetrics (DGGG) provides for drug therapy as a first step in the case of endometriosis in the lungs and a possible concomitant catamenial pneumothorax. Medications that downregulate estrogen levels can be used. Progestogen preparations or GnRH agonists are among them. If it becomes clear that the administration of drugs does not lead to the desired success, surgical intervention may be considered. Particularly good results can be achieved with a laparoscopic-thoracoscopic combination. In this procedure, the thoracic cavity and the abdominal cavity are examined in equal measure. This ensures that all endometriosis lesions in the area are detected. According to the guideline program of the German Society of Gynecology and Obstetrics, it is recommended that hormone suppression, in this case estrogen suppression, be performed following surgery. In this way, the risk of recurrence can be reduced.[1],[2],
Good to know!
Both diagnosis and treatment should include a gynecological evaluation. In addition, it is important to analyze the female menstrual cycle and observe the complaints in the lung area.[1]
In a nutshell
Endometriosis in the lung is rare. Symptoms tend to be nonspecific and thus are often not directly associated with endometriosis. Possible symptoms include chest pain, blood pooling in the chest (hemothorax), and pain radiating to the shoulder. Catamenial pneumothorax, also called menstrual pneumothorax, is associated with endometriosis. In this case, there is an accumulation of air in the chest and symptoms such as shortness of breath. Endometriosis in the lungs can be detected in the pleura, diaphragm or lung parenchyma, the tissue associated with breathing. Medical professionals call this “thoracic endometriosis syndrome (TES).” Why the tissue settles in the lungs is not yet entirely clear. Diagnosis relies primarily on imaging and bronchoscopy with associated biopsy. If it is certain that there is endometriosis in the lungs, conservative treatment with medication can be used. The focus here is on lowering the estrogen level. If the desired results cannot be achieved with medication, surgery is also a possibility. In this case, however, suppression of selected hormones with the aid of medication should also be planned in order to reduce the risk of recurrence.
References
- Pharmaceutical Companies and Their Influence on Scientific Research - 7. October 2023
- Identification of a Genetic Factor Linked to Endometriosis Development and Potential Therapeutic Targets - 6. October 2023
- Identification of a Genetic Factor Linked to Endometriosis Development and Potential Therapeutic Targets - 6. October 2023