How Pleurodesis Treats Mesothelioma
A pleurodesis is a palliative treatment for mesothelioma patients experiencing pleural effusions. Undergoing a pleurodesis does not improve survival rates and has no curative capabilities. However, the treatment does improve a patient’s overall quality of life by alleviating symptoms caused by the buildup of fluid.
Pleural Effusion Symptoms
- Breathlessness (dyspnea)
- Dry cough
- Dull chest pain
If a malignant mesothelioma patient presents with pleural effusion symptoms, their doctor will use imaging scans to confirm the fluid buildup. Pleural effusions are detectable on chest X-rays and CT scans. Once the pleural effusion is confirmed, the patient and their healthcare team must decide how to best treat the condition.
There are two palliative treatment options for pleural effusions, a pleurodesis or a pleurocentesis. A pleurodesis is the more invasive of the two possible procedures. While the pleurodesis involves closing the pleural cavity to prevent the fluid buildup, a pleurocentesis drains the excess fluid using a needle. A pleurocentesis may be completed multiple times for symptom relief and may be used on patients who have undergone pleurodesis with recurring fluid buildup. Between 10 – 40% of patients experience recurring fluid accumulation following a pleurodesis. Patients that decline the repeated pleurocentesis may treat the recurrence with an indwelling pleural catheter, a small tube specifically designed to remove fluid from the lungs.
If a pleurodesis is deemed the best treatment option for a patient’s specific case, the procedure may be completed one of three ways: chemical injection to cause irritation, mechanical irritation or a rapid procedure, which involves chemical injection and use of a pleural catheter.
During chemical pleurodesis, a patient’s malignant pleural effusion is treated through the injection of a chemical substance into the pleural space. When introduced to the body, these medications, called sclerosing agents, irritate the tissue and cause inflammation. This inflammation inhibits further fluid accumulation. Mesothelioma doctors commonly use talc or doxycycline to adhere the two layers of the pleura (lung linings) together.
A talc slurry, made from a talc and saline mixture, is most often used as the sclerosing agent in a chemical pleurodesis. After any excess pleural fluid is drained from the pleural space, the talc slurry is administered through a chest tube between the lung and the chest wall. The patient will need to change positions during the procedure to fully coat the chest cavity in the sclerosing agent. The entire procedure may take a few hours to complete. Following a chemical pleurodesis, a patient may experience mild discomfort. A chemical pleurodesis is often completed under anesthesia to ensure patient comfort.
According to a 2017 retrospective study, malignant pleural mesothelioma patients treated with talc pleurodesis achieved a mean survival of 14 months. In general, pleural mesothelioma patients’ median survival time is six months to one year following diagnosis.
While talc has shown to be the most favorable chemical used for pleurodesis, patients who have compromised respiratory function may benefit from other sclerosing agents. Studies have found those with preexisting respiratory compromise may be at greater risk for acute respiratory distress syndrome (ARDS) following a talc pleurodesis. A patient’s medical team will be able to discern if chemical pleurodesis is the best option for their specific case, as well as what sclerosing agent would be the most beneficial and safe.
Mechanical or Surgical Pleurodesis
A mechanical or surgical pleurodesis is a more invasive procedure than chemical pleurodesis. Pleurodesis achieved mechanically involves manual irritation of the pleura. Doctors achieve the desired inflammation through use of rough materials including gauze, pads or surgical tools.
Studies show that pleural fluid buildup treated with a mechanical pleurodesis may be less likely to recur when compared to pleural effusion treated with other treatment modalities. A 2015 study analyzing pleural effusion in patients with breast cancer found those treated with mechanical pleurodesis had better symptom control than those treated with a chemical pleurodesis. Researchers also found mechanical pleurodesis to be a safer procedure to complete than chemical pleurodesis.
A rapid pleurodesis is a combination of chemical pleurodesis techniques and the use of a catheter instead of a larger chest tube. Using a tunneled pleural catheter (TPC, most commonly a PleurX catheter) allows for a shorter hospital stay compared to the other pleurodesis options. Typically, patients are only hospitalized for two days following the rapid pleurodesis procedure. Patients who undergo the other pleurodesis types may stay in the hospital for up to 10 days following their procedure.
One retrospective study from 2016 found 29 patients with pleural effusions treated with rapid pleurodesis experienced reduced dyspnea (breathing difficulties) and improved quality of life following the procedure. While uncommon, the study did have one participant incur a lung injury due to the talc particles used during the procedure. This injury emphasizes the need for patients to understand the potential risks of a procedure, regardless of how common and typically safe a treatment is considered. Additionally, the study found patients recently treated with chemotherapy required a catheter for longer than patients who hadn’t undergone the treatment type. Patients who’ve been treated with chemotherapy in the past should discuss the potential impact of that treatment on their recovery from a rapid pleurodesis with a medical professional before treatment.
Resources for Mesothelioma Patients
Eligibility for Mesothelioma Pleurodesis
Due the variety of pleurodesis treatments available, many pleural mesothelioma patients are eligible for one of the procedure types. The procedure is best tolerated by patients whose mesothelioma is still in the early stages, which may also be used in conjunction with more aggressive surgeries.
Once the cancer has metastasized, or spread, and overtaken the pleural cavity, a patient may no longer be eligible for the procedure. Patients with trapped lungs (from pleural tumors that inhibit lung expansion) are not eligible for pleurodesis. Additionally, pleurodesis is not a viable treatment option for mesothelioma patients whose tumors have blocked an airway or those that have pleural loculation (fibrotic scar tissue that prevents fluid drainage).
03. Side Effects and Risks
Side Effects and Risks of Pleurodesis
Depending on the type of pleurodesis a patient undergoes, their hospital stay can vary from just two days to more than 10 days. Following release from the hospital, a patient’s lung function may remain impaired for approximately six months after the procedure. This impairment is due to the necessary scarring incurred to achieve the closing of the pleural space. Total lung function should return six months after the pleurodesis.
Besides the desired scarring, pleurodesis side effects are generally mild. Most commonly, patients will only experience mild chest pain and slight fever after the procedure. Pleural mesothelioma patients that have undergone chemotherapy within one month of their pleurodesis may be at a greater risk of infection following the procedure due to a suppressed immune system.
Common Side Effects of Mesothelioma Pleurodesis
- Chest pain
- Hypoxemia (low oxygen concentration in the blood)
- Hypotension (low blood pressure)
- Rarely, lung injury
- Tachycardia (rapid heart rate)
No thoracic surgery is without risks, though for many, these may be outweighed by the potential benefits. Risks are exacerbated if patients undergo a pleurodesis when they’re not the best fit for the procedure. According to one study, some 30% of patients that are recommended for pleurodesis are unfit and would be better served with a pleurocentesis or other treatment.
For appropriate patient populations, a pleurodesis may help to mitigate shortness of breath and other uncomfortable effects of a pleural fluid buildup. Reducing the amount of fluid has been shown to improve overall quality of life for patients. Clinical trials are underway to further improve pleurodesis outcomes in order to best treat pleural mesothelioma patients.
When the pleurodesis is completed by an experienced mesothelioma doctor, existing risks may be reduced. A patient’s healthcare team can discern which pleural effusion treatment is most beneficial for their specific mesothelioma case.