Surgery is one of the major therapeutic modalities used in the treatment of mesothelioma. There are a number of procedures available and the doctor’s decision on which to perform will be based on each patient’s individual presentation. Important factors to be considered will include the overall treatment strategy, the disease’s histology, location and stage, as well as the patient’s general health and performance status. Improvements in surgical techniques and post-operative treatments have resulted in a higher “success” rate for many of these procedures, as well as a major reduction in perioperative and postoperative mortality rates. However, serious complications do still occur, so the decision to perform extensive surgery should always be very clearly considered.
Surgery – Surgical Strategies
There are two major surgical strategies employed in the management of this cancer: palliative surgeries and surgeries with curative intent. Palliative surgeries are procedures that treat particular symptoms of cancer without aggressively treating the disease itself. These surgeries run from low-impact, supportive care of the disease to aggressive attempts at individual symptom control (even though the underlying disease itself won’t be treated aggressively).
The goal of the surgeries with curative intent is to remove as much of the malignancy as possible. Ideally, this would mean that all of the cancer would be removed, but the disease’s complex growth pattern makes complete removal a very difficult task. Unlike other forms of cancer that present as individually-identifiable tumors with clear boundaries between the tumor and surrounding tissues, mesothelioma presents as a diffuse malignancy that spreads throughout a surface area. It generally appears as a sheath-like layer of malignant tissue made up by a large number of individual tumors, too numerous to individually remove. The boundaries between the malignant area(s) and the surrounding healthy tissues are often indistinct, which can complicate the decision on where to begin the extraction, as well as obscure the true extent of infiltration. This means that occult disease may remain after resection. Occult disease refers to microscopic cancer cells that are hidden or too small to be seen during surgery or post-operative analysis, but which are alive and still able to grow. When occult disease is present, the cancer will continue to grow and to return unless some type of post-surgical treatment is attempted to eradicate these cells.
In light of this issue, oncologists have concluded that surgery is rarely effective as a single modality therapy and that it must be combined with other therapeutic modalities to maximize patient survival time. The goal of surgery, then, is to achieve a macroscopically-complete resection, which refers to the removal of all visible tumor cells, and then adjuvant therapies will be used to treat the potential for occult disease.
Curative Surgery – Extrapleural Pneumonectomy
Pleural mesothelioma is a form of lung cancer that is almost always caused by asbestos exposure and is most commonly found in the outer lining of the lungs called the mesothelium. Although there are no cures for mesothelioma, it can be treated with varying degrees of success through the use of surgical procedures, chemotherapy and radiation.
Most often a diagnosis is not made until symptoms appear and the disease has progressed to an advanced stage leaving the patient with life-threatening complications. Early detection, however, can positively influence a patient’s prognosis by increasing treatment options and improving their quality of life while battling the cancer.
The goal of surgery is to achieve a macroscopically-complete resection, which refers to the removal of all visible tumor cells, however, the cancer often has a complex growth pattern making complete surgical removal a very difficult task.
An extrapleural pneumonectomy is a complex surgery for mesothelioma that features the removal of the affected lung and parietal pleura, as well as the possible removal of the diaphragm, the pericardium and other extrapleural tissue. The visceral pleura is attached to the lung and is therefore removed with it. Extrapleural pneumonectomy is an extensive and invasive surgery, but for the majority of patients with pleural mesothelioma, treatment protocols featuring it represent their best chance for long-term survival.
Extrapleural Pneumonectomy – Overview of the Procedure
Extrapleural pneumonectomy (EPP) is considered radical surgery due to the extensive amount of tissue resection attempted during the procedure and the highly invasive techniques necessary to complete the operation. Patients who undergo the procedure face an extended recovery period and serious complications are not uncommon. However, EPP-based treatment protocols are often the most effective at increasing survival times and improving prognosis.
Extrapleural pneumonectomy requires a posterolateral thoracotomy for entry into the interior of chest. The incision is likely to be even more extensive than a standard thoracotomy incision and is done to give the surgeon greater exposure to the patient’s thorax. In some cases, the 6th rib may be removed to facilitate entry into the pleural cavity. When the surgeon reaches this area, he or she will then begin the actual resection.
The parietal pleura and the area surrounding it are the surgeon’s initial target, and then he or she will move to the lung itself. Once both of the lungs have been freed from their adjacent tissues, the surgeon will move on to the diaphragm and pericardium. The degree to which these structures will be resected depends on how extensively the disease has infiltrated them, as well as on the personal preference of the surgeon conducting the operation. Some physicians feel that both the diaphragm and the pericardium should be removed even if they do not show any signs of infiltration, while other surgeons feel they can be safely left alone if there is no evidence of malignancy. In most cases though, at least a partial resection of the diaphragm and pericardium is likely. If these structures are removed, they will be reconstructed using a mesh fiber that has been designed to replace the tissues and the supporting functions they previously performed.
At certain points during the procedure, the surgeon will also remove lymph nodes located in adjacent areas, as well in surrounding tissue structures, for post-operative staging analysis. The lymph nodes will be packaged and identified, and then sent to a pathologist for analysis. This information will inform the follow-up treatment options that the patient may undergo.
Once all of the tissues have been resected and the diaphragm and pericardium reconstructed if needed, the surgeon will begin the exit procedure. Complications are not uncommon with extrapleural pneumonectomies, so the surgeon will check to make sure that everything has been properly completed and is in the appropriate state. Drainage tubes will be inserted in various locations to ensure fluid dissemination from the pleural cavity and surrounding areas. This should enable proper lung expansion and will aid in patient recovery. Should everything be order, the surgeon will step backward through each of the steps made during the initial approach, reconstructing and reattaching tissues that had to be cut during entry and closing up incisions as he or she goes along.
After surgery, the patient will be moved into the Intensive Care Unit for a few days of monitoring and initial postoperative recovery. The first 3-5 days of postoperative care are exceptionally important to maximize a patient’s recovery and long-term health. Extrapleural pneumonectomy and thoracotomy are major operations and feature significant post-operative healing, so it is important for patients to take their recovery slowly.
Extrapleural Pneumonectomy – Treatment Considerations
Historically speaking, extrapleural pneumonectomy was associated with significant perioperative or postoperative mortality rates, as well as a high number of serious complications. Advances in surgical technique and greater experience with the procedure have significantly lowered the mortality figures, but serious complications are still possible. Mortality rates have now dropped below 5%, but serious treatment complications are commonly described in around 30% of cases.
Despite this high complication rate, surgeons generally feel that if a patient is a candidate for an EPP then the patient should definitely undergo the procedure. Most of the complications associated with extrapleural pneumonectomy are now fairly well-known, so even if surgeons aren’t able to prevent their occurrence, they are at least able to plan for the likelihood of occurrence and will be ready to adjust should one appear.
Extrapleural Pneumonectomy vs. Pleurectomy-Decortication
A recurrent question in mesothelioma treatment has been to what extent extrapleural pneumonectomy should be chosen over pleurectomy-decortication and what, if anything, it “means” to choose one procedure over the other. Many people have thought that the treatments were relatively interchangeable and that meant pleurectomy-decortication was then the “better” option because it preserves the lung, while extrapleural pneumonectomy was the “worse” option because it was more radical and could take longer to recover from. However, studies have generally concluded that the two procedures are not interchangeable: they have different domains of application and are most effective for patients in different stages of the disease. Pleurectomy-decortication is generally performed on patients who present with locally-contained asbestos cancer that only evidences a sparse advancement into adjacent tissues offering better relief of the symptoms, while extrapleural pneumonectomy is most-often used for patients who exhibit more extensive spread of the disease.
The goal of all curative surgeries for mesothelioma is to achieve a macroscopically-complete resection, so the procedure that can best achieve that is in fact “the better” procedure for an individual patient. During the disease’s earliest stages, a pleurectomy-decortication may be all that is needed to achieve macroscopically-complete resection. For patients lucky to be diagnosed with this limited tumor burden, pleurectomy-decortication is likely to be a good option. However, for patients who present with more extensive tumor infiltration—which is the majority of the diagnoses—extrapleural pneumonectomy will be the surgery of choice because it is more likely to achieve a macroscopically-complete resection than is a pleurectomy-decortication.
In many instances, a surgeon will not know which procedure will be performed upon beginning thoracotomy. If preoperative imaging scans show only sparse tissue infiltration, the surgeon may assume that pleurectomy-decortication will be performed, but if, upon entry into the pleural cavity, it is discovered that CT or MRI failed to disclose the extent of the malignancy, the surgeon will then attempt an extrapleural pneumonectomy. Although less likely, the opposite could be true as well: the surgeon may begin thoracotomy with the assumption of extensive tissue infiltration and, therefore, the performance of an EPP, but upon entry into the pleural cavity, the surgeon may see a smaller area of infiltration and a PD will be performed instead.
Extrapleural Pneumonectomy – Conclusion
Extrapleural pneumonectomy is the standard curative surgery in many of the multimodal treatment protocols currently under investigation for the treatment of pleural mesothelioma. Because the disease is most often diagnosed after it has had a chance to spread, an EPP represents the best chance that most patients have to achieve a macroscopically-complete resection, which is the end goal that most mesothelioma specialists have identified as the strategic point of surgery. Extrapleural pneumonectomy is not available to all patients, but for those who are eligible to receive it, a number of studies have shown that an EPP performed as part of a multimodal treatment protocol can lead to longer—sometimes, significantly longer—median survival times for these patients.
Surgery – Techniques
Most surgeries that are performed for mesothelioma are completed by physicians trained as thoracic surgeons, that is, physicians who are experts in surgeries performed in the chest area, whose medical name is the thorax. Our chests contain two of our most vital organs—the heart and the lungs—so surgeries performed in the area require great skill and careful treatment, as well as excellent post-operative procedures that can maximize recovery, while attempting to minimize complications. One of the most important factors to achieving these goals is the surgical technique used for entry into the chest.
Two major techniques for entry are currently employed in most thoracic surgeries: thoracotomy and video-assisted thoracic surgery (VATS). To learn more about these procedures, please read through the summaries below and follow the “Learn More” link for greater background detail.
- Thoracotomy is a surgical procedure where a large incision is made to the chest so open surgery can be performed. It is a highly invasive technique, but is necessary for the completion of the curative surgeries.
- Video-Assisted Thoracic Surgery (VATS)
- Video-assisted thoracic surgery (VATS) is a minimally-invasive surgical technique that uses video imaging to guide the surgeon. VATS has replaced thoracotomy for a number of procedures, as it allows the same or similar treatments, but accomplishes them in a much less invasive manner.
Thoracotomy – Overview of the Procedure
The patient will be given general anesthesia before the incision and will be closely monitored during the thoracotomy and subsequent surgery. When the operation is ready to begin, the patient is placed on his or her side, with one shoulder and side facing up and the other tucked under the body. The side that is facing up is the side through which the surgeon will enter the body. The patient is secured in this position so he or she can’t be moved during the surgery. The patient’s legs and knees are positioned in a way to maximize blood flow and to prevent the development of any complications during surgery.
The surgeon is likely to mark the incision path on the exposed skin using a marker or felt-tipped pen. This path will follow the course of the underlying ribs. When the surgeon begins the incision, he or she will make multiple passes along this path, with each pass cutting through another layer of tissue, each one deeper that the next.
The surgeon will soon be faced with how to proceed through the latissimus dorsi, which is the large muscle that proceeds along the lateral side of the body and is involved in most movements of the body’s trunk. Traditional posterolateral thoracotomy cut through this muscle, which can significantly increase recovery time, while modern methods can sometimes fully or partially preserve the muscle, but at the expense of less thoracic exposure and longer time in surgery. The decision on how to perform this part of a thoracotomy will be determined by the surgeon.
Upon reaching the rib cage, the surgeon will use a rib spreader, which is a device that will expand the space between two ribs, to gain access to the organs and tissues contained therein. Once the spreader has been secured, he or she can then begin whatever procedure the thoracotomy was conducted for.
Upon completion of the intended procedure, the surgeon must backtrack his or her way out of the patient’s chest, one step at a time, being just as careful with his or her technique as during this exit as during the initial entry. After the procedure has been completed, the patient will be moved into the Intensive Care Unit for post-operative monitoring and then from ICU if he or she does not show any signs of post-operative complications.
There is often an extended recovery period for procedures involving thoracotomy.
Video-Assisted Thoracoscopic Surgery (VATS)- Overview of the Procedure
Video-assisted thoracic surgery (VATS) is a relatively recent advancement in the practice of thoracic surgery and has excellent application to the diagnosis and treatment of mesothelioma. It is a less-invasive technique than is thoracotomy and is associated with better patient response than is the traditional procedure.
In a VATS procedure, at least two small incisions are made in the patient’s side. The thorascope is inserted through one of the incisions, and the diagnostic/surgical instruments are inserted through the other(s). The thorascope is attached to a monitor that allows the surgeon to see a detailed view of the pleural cavity, the lungs and its surrounding tissues. Using the tools inserted through the other incision(s), the surgeon can then complete the chosen diagnostic test or surgical treatment without ever having to physically see inside the patient’s body. This is the feature that gives VATS a greater efficacy than thoracotomy: thoracotomy uses a large incision because doctors have traditionally required an entry point that allows good exposure of the interior spaces, while VATS can be deployed through small incisions that do not require the removal or transection of large muscles and tissue structures.
VATS can successfully be applied to many of the procedures that are associated with mesothelioma treatment and diagnosis. It allows the exploration of the visible tissue structures in the chest, as well as the removal of tissue or fluid samples for biopsy. VATS aids in the staging of patient disease through an analysis of tissue appearance and may also be used for lymph node resection if lymph node involvement is suspected. Surgically speaking, VATS represents a major improvement in the palliative use of pleurectomies and decortications.
VATS is also used to treat a variety of other cancers, including lung cancer.
Palliative Surgery – Debulking Pleurectomy
A debulking pleurectomy is a surgical procedure that attempts to reduce the gross volume of malignant disease without attempting a complete resection of all cancerous tissue. It can be performed in addition to pleurodesis to better control fluid build-up and prevent the recurrence of pleural effusions and the symptoms associated with them. The reduction in tumor volume after a successful procedure may also have therapeutic benefits, but a debulking pleurectomy is only attempted to control the symptoms associated with the disease—it is not considered a curative approach to the treatment of pleural mesothelioma. When the procedure is performed in a curative manner it is considered radical surgery and is completed in combination with a decortication of the lung and full resection of the visceral pleura. To learn more about the use of pleurectomy-decortication for the curative treatment, please read our article: Mesothelioma Treatment: Curative Surgery – Pleurectomy-Decortication.
Debulking Pleurectomy – Overview of the Procedure
The goal of a debulking pleurectomy is a reduction in gross tumor volume through resection of the parietal pleura. The procedure is also referred to as a subtotal debulking parietal pleurectomy. The extent to which the surgeon will excise the entire parietal pleura, only part of it, or the full pleura along with some diseased tissue that extends beyond it will be determined at the time of surgery, where the surgeon’s decision will be based on overall tumor burden, patient health, performance status and expected recoverability.
Debulking pleurectomy has traditionally been completed through a thoracotomy, but contemporary treatment protocols call for the use of video-assisted thoracoscopic surgery (VATS) techniques. As is the case with many thoracoscopic procedures, VATS techniques have increased the efficacy of the surgery while reducing operative complications. A number of studies have found both survival and quality-of-life benefits to successful VATS pleurectomies.
Pleurectomy performed through thoracotomy is no longer recommended for most patients. Due to its association with significant post-operative complications, it is difficult to recommend this form of pleurectomy for palliative purposes.
Debulking Pleurectomy – Treatment Considerations
Debulking pleurectomy is a potentially beneficial palliative treatment for pleural mesothelioma patients who are not eligible for radical surgery, but a number of factors must be considered before a final decision can be rendered. The most important of these focuses on the type of procedure deployed for the surgery. As we said above, VATS procedures are more effective than ones performed through thoracotomy, but not all patients are eligible for VATS. A major problem for successful VATS procedures is scar tissue from previous thoracic surgeries, so patients who have had prior chest surgeries are less likely to be eligible for VATS. For these patients, thoracotomy may be the only option for a debulking pleurectomy, but this raises questions about treatment response and expected survivability in a palliative context. In this situation, the benefits to the symptom control expected from pleurectomy must be weighed against the hazards of a highly invasive procedure.
Another important consideration is overall patient health and stage. Patients who may candidates for surgeries with curative intent, such as radical pleurectomy-decortication or extrapleural pneumonectomy, will not undergo a debulking pleurectomy if their physician feels a better long-term outcome is possible with the radical surgeries. At the other end of the spectrum, patients with very advanced disease will only be treated for local symptom control and pain management, as more serious surgeries will not be an option for them.
Debulking Pleurectomy – Conclusion
A successful debulking pleurectomy can have significant benefits to patients with pleural mesothelioma, especially when performed in addition to pleurodesis. Treatment of pleural effusions and relief from the dyspnea associated with them are the primary endpoints of the procedure. While the reduction of tumor volume is not considered a curative approach to treatment, some studies have identified a survival benefit to patients who undergo debulking pleurectomy.
Pleurodesis for Mesothelioma
A pleurodesis is a procedure that fuses together the parietal pleura and the visceral pleura, thereby obliterating the space between them. It is the most commonly-performed palliative treatment for patients with pleural mesothelioma because it helps prevent the most common symptom of the disease: pleural effusions, which are the result of fluid that builds-up in the pleural space. Pleural effusions can be quite painful and directly lead to shortness of breath (dyspnea), so a successful pleurodesis is an effective way to reduce some of the burdens associated with the disease.
Pleurodesis – Overview of the Procedure
Before the actual pleurodesis can be performed, the patient must have all of the fluid drained from his or her pleural cavity. Once the effusion has been drained and the pleural space emptied of fluid, the procedure can then begin. A pleurodesis is most commonly performed by introducing a chemical agent onto the surfaces of the two pleurae which causes surface irritation and inflammation. The pleural space is actually quite small, so the inflamed pleurae have only a small area in which to grow before their surfaces touch and the chemical “fusion” can be completed. A number of different agents have been used in the past, but contemporary treatment protocols specify talc as the standard agent deployed.
Although a chemical pleurodesis is the most common manner of performing pleurodesis, the procedure can also be performed surgically. In these situations, it is performed through thoracotomy or video-assisted thoracoscopic surgery (VATS). In a surgical pleurodesis, the surgeon will irritate one of the pleura—usually the parietal pleura—with a surgical instrument that causes it to become inflamed. The swollen pleura is then treated and fused to the visceral pleural, eliminating the space between them.
Pleurodesis – Treatment Considerations
Even though pleurodesis is an effective treatment for most patients with pleural mesothelioma, there are some downsides to the procedure. It can be quite painful to undergo, especially when performed through thoracotomy, so the patient must be sedated and then treated for the pain post-operatively.
However, the major problem associated with the procedure is that undergoing it can complicate further treatment. Because the very nature of the procedure is to bind together the pleural surfaces, curative surgical procedures whose effectiveness is based on the extraction of these tissues become more difficult, if not impossible, to perform. This is especially true for pleurectomy-decortication, where the visceral pleura and the parietal pleura are the major targets for resection. Patients who are set for an extrapleural pneumonectomy will be less compromised after pleurodesis compared to pleurectomy-decortication patients, but even for this group, a pleurodesis can complicate their surgery because the procedure adds another level of complexity to an already difficult surgery with historically high complication figures.
Pleurodesis – Conclusion
A pleurodesis will generally be performed on only those patients who are being treated palliatively. For patients who are not able to tolerate more advanced surgeries, such as a pleurectomy/decortication or an extrapleural pneumonectomy, successful pleurodesis is an effective treatment option in the management of symptoms. It can be combined with other treatments, such as palliative pleurectomy or a palliative decortication of the lung, for greater control of patient symptoms. However, for patients who may be candidates for curative surgeries, other options should be explored for the treatment of recurrent pleural effusions.