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PTS500 MPE
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About PTS500-Malignant Pleural Effusion (MPE)


(Picture Source: American Thoracic Society)


 

The lungs and chest wall are both lined with thin membranes called “pleura”. The space between the lungs and the chest wall is called “pleural space”. Usually, the two thin membranes are close together, and there is only little fluid (about 5-15 ml) in the pleural space as a lubricant for the expansion of the lungs during breathing.
 

When effusion is an abnormal build-up in the pleural space, the lungs will be compressed, and the fluid is called “pleural fluid” or “pleural effusion”.
 

The normally little pleural effusion will increase in certain diseases. When osmotic pressure changes in a systemic disease cause an increase in pleural effusion, this pleural effusion is usually “transudate”. On the other hand, when chest-related diseases such as pneumonia and malignant tumors cause local inflammation of the lungs, this pleural effusion is mostly “exudate”.
 

If the cause of the effusion is due to cancer cells in the fluid, the effusion is called a “malignant pleural effusion (MPE)”.
 

MPE is the buildup of fluid and cancer cells between the chest wall and the lung. Depending on the degree of malignancy, a great amount of fluid may compress lung causing dyspnea, cough and chest pain and severely reducing patient’s quality of life.
 

The symptoms of a MPE can be extremely variable and sometimes patients have no symptoms. Below is a list of common symptoms of MPE:

  • Shortness of breath at rest or with activity
  • Chest pain or pressure
  • Cough
  • Pain when taking a deep breath, or the feeling of not being able to take a deep, satisfying breath
  • Fever
  • Fatigue

In the early stage of lung cancer, only 15% of patients will develop MPE, and about 50% of cancer patients will have MPE in the middle and late stages of their disease. High morbidity cancer like lung cancer and breast cancer account for about 50-65% of MPE [1]. Once MPE is diagnosed, depending on the cause of malignancy, the average survival period is between 3 to 12 months [1]. Also, if a lung cancer patient has MPE, it is defined as stage IV lung cancer based on the definition of lung cancer staging.
 

The treatment of MPE is aimed at palliating symptoms and maintaining life quality since no intervention has been shown to improve survival in this population.
 

The current recommendation for MPE management is pleurodesis by chemical (talc or other agents) or physical (indwelling pleural catheter, IPC) approaches to obliterate the pleural space for MPE accumulation. Care must be taken to control the particle size of talc to avoid complication such as acute respiratory distress syndrome (ARDS); IPC would require weeks before successful pleurodesis may take effect, and risks of infection have been reported [2].
 

In either case, pleurodesis leads to adhesion between the parietal and the visceral layers of the pleura without killing the cancer cells in the pleural cavity. Therefore a safe and effective option to treat MPE is still in need.

 

Reference
 

[1] Clinico- pathological profile and course of malignant pleural effusion in a tertiary care teaching hospital in western U.P. with special reference to lung cancer. Lung India. 2015 Jul-Aug; 32(4): 326–330.
 

[2] Fenton KN, Richardson JD., Diagnosis and management of malignant pleural effusions. Am J Surg 1995;170:69-74.Feller-Kopman DJ, et al. 2.Management of malignant pleural effusions. An official ATS/STS/STR clinical practice guideline. Am J Respir Crit Care Med. 2018 Oct 1;198(7):839-849.