Peritoneal Mesothelioma Stages

Quick Summary

Peritoneal mesothelioma is an exceedingly rare diagnosis, with only around 500 new cases per year in the United States. Because it’s so rare and often isn’t diagnosed until it has reached significant metastasis (spreading), it’s difficult for specialists at this time to form an official peritoneal mesothelioma staging system. Instead, doctors describe a patient’s condition as early or advanced to help them determine which treatment options are available.

Peritoneal Mesothelioma Stages Overview

If you’ve been diagnosed with peritoneal mesothelioma, then here are some important things to know about the stages of this disease:

  • Unlike pleural mesothelioma, which doctors stage 1 to 4, peritoneal mesothelioma has no official staging system
  • Peritoneal mesothelioma is described as either early or advanced stage
  • Early stage peritoneal mesothelioma is still respectable by surgery
  • Late stage peritoneal mesothelioma is unlikely to be resectable by surgery
  • Peritoneal mesothelioma treatments and therapies exist no matter how far advanced the condition is
  • There are peritoneal mesothelioma specialists available now to treat your condition at any stage

What Are the Peritoneal Mesothelioma Stages?

Cancer staging is an important part of oncological care. Doctors need to look at different criteria for a patient’s condition to determine which treatment options are available and which ones will be most effective. Staging systems give doctors the criteria to help them make these decisions.

Unlike more common cancers which all have established and well-known staging systems, peritoneal mesothelioma does not yet have an official staging system.

Generally, doctors look at how far advanced the spreading is to help them determine which peritoneal mesothelioma treatments to use.

Peritoneal Mesothelioma Categories

A common cancer staging system is the TNM system, which looks at the tumor status (T), the lymph node involvement (N), and the rate of metastasis (M).

TNM staging can be used to help give specialists more details about a peritoneal mesothelioma case. Doctors may also use a general 1-4 categorization of peritoneal mesothelioma to determine its status.

Category 1 represents a fully resectable tumor contained to the abdominal cavity, while category 4 represents tumor growth outside the abdominal cavity.

Dr. Claire Verschraegen, one of the most experienced peritoneal mesothelioma specialists and researchers, has said that she uses 4 different categories of pleural mesothelioma:

  • Category 1: A fully resectable, localized tumor
  • Category 2: Tumors contained to the abdominal cavity’s peritoneal and organ surfaces that can only be debunked
  • Category 3: Mesothelioma spreads into organs but is still contained within the abdominal cavity
  • Category 4: Mesothelioma has spread outside the abdominal cavity and is now in the lymph nodes

Though these categorizations are helpful in determining effective treatments, Dr. Verschraegen also stresses that:

“Because of the uncertainty of these definitions, these numbers have to be taken cautiously.”

She also notes that based on this categorization, a completely localized peritoneal mesothelioma tumor at diagnosis is really rare in her experience.

Localized vs. Advanced Peritoneal Mesothelioma

Because doctors typically refer to cancer in terms of localized or advanced it’s helpful if patients understand exactly what is meant by this terminology.

By nature, cancer is a condition whereby healthy cells mutate and turn into unhealthy cells. These unhealthy cells grow and divide and abnormally high rates and don’t undergo normal apoptosis—the natural process of cells dying off. If cancer cells aren’t controlled through treatment, they will continue to grow and spread outward to distant sites.

The processing of spreading outward to distant sites is called metastasis. The more metastasis involved in a patient, the more advanced it is.

Localized mesothelioma means that the cancer cells (or masses of cancer tissue called tumors) are still contained to the initial site where the mesothelioma formed—the primary location. Localized mesothelioma means that cancer hasn’t yet had enough time to spread to distant sites, thereby making it still an early-stage disease.

Once the mesothelioma cells are found outside the primary location, it is considered an advanced condition due to the metastasis.

Resectable vs. Unresectable Peritoneal Mesothelioma

Using imaging scans, doctors can tell how far the mesothelioma has spread within the abdominal cavity.

With this information, surgeons can determine if they believe the tumor is resectable or not. Resectable refers to the ability for the tumor to be removed through surgery.

If a tumor is resectable, then specialists will recommend a potentially curative procedure called complete cytoreduction. Complete cytoreduction refers to removing all (or nearly all) visible signs of the tumor.

If the tumor remains unresectable, then doctors may still use cytoreduction (incomplete cytoreduction) to remove parts of the tumor even though the goal is no longer curative. Removing parts of the tumor through cytoreduction can help improve a patient’s quality of life.

Factors That Affect Peritoneal Mesothelioma Progression

Factors of Progression Update

Patients who have been diagnosed with peritoneal mesothelioma should be aware of different factors that affect how the disease spreads, which ultimately determines how advanced the condition may be.

Doctors look at peritoneal mesothelioma progression factors such as:

  • Patient health: The body’s immune system plays a key role in being able to combat mesothelioma. Healthy patients have healthier immune systems, which can contribute to a slower metastasis. Unhealthy patients have weakened immune systems, which allow mesothelioma to spread faster.
  • Cell type: There are two mesothelioma cell types that also determine the rate of metastasis. Epithelioid cell type has a more favorable prognosis while sarcomatoid cell type has a worse prognosis. A biphasic tumor is composed of both cell types, and its prognosis is determined by the ratio between epithelioid and sarcomatoid cell types.
  • Response to treatment: How quickly peritoneal mesothelioma advances is also based on how the individual patient responds to treatment. Different patients respond differently to various treatment approaches, especially certain types of chemotherapy drugs. Patients who respond favorably to treatments will experience a slower disease progression.

Early-Stage Peritoneal Mesothelioma Treatments

Peritoneal mesothelioma patients who are deemed to be in early-stage are usually eligible for a curative procedure called cytoreduction with HIPEC. Developed by Dr. Paul Sugarbaker, and coined the “Sugarbaker Technique”, cytoreduction with HIPEC is a two-part procedure that can dramatically improve the life expectancy of peritoneal mesothelioma patients.

Here is what is involved in cytoreduction with HIPEC:

  1. Cytoreduction Surgery: Surgeons open up the abdominal cavity and remove all visible signs of tumors. Typically, surgeons will remove the diseased peritoneum (peritonectomy), which is the abdomen lining. If any tumors are present elsewhere around other abdominal organs, surgeons will remove these as well.
  2. HIPEC: After cytoreduction and while the abdominal cavity is still open, doctors administer HIPEC—a heated chemotherapy drug combination—directly into the abdomen. The drugs circulate throughout the abdomen, bathing the organs in chemotherapy and killing off as many remaining mesothelioma cells as possible.

Different studies have shown that the cytoreduction with HIPEC technique on early-stage peritoneal mesothelioma patients can result in a life expectancy between 2 and 5 years.

Late-Stage Peritoneal Mesothelioma Treatments

Once a patient’s condition has reached advanced stages with significant metastasis, curative surgical procedures are no longer available. Instead, doctors focus on administering treatments that will make the patient as comfortable as possible. Some of these treatments, referred to as palliative therapies, may also help improve life expectancy though they may not lead to long-term survival.

The combination of chemotherapy and radiation is a standard late-stage peritoneal mesothelioma treatment. This combination helps to shrink tumors and slow down disease progression, which alleviates painful symptoms caused by metastasis to distant sites.

Pleurodesis is an important palliative surgery for peritoneal mesothelioma patients. During a pleurodesis, doctors drain fluid buildup (ascites) from the abdominal cavity to relieve swelling and pressure.

Seeking Treatment and Compensation for Peritoneal Mesothelioma

Peritoneal mesothelioma patients have a favorable prognosis compared to pleural or pericardial mesothelioma patients. Treatments, when sought early enough, can significantly improve life expectancy and may even lead to long-term survival.

If you’ve been diagnosed with peritoneal mesothelioma, then you may be eligible for legal compensation. As a victim of asbestos exposure, you have several legal courses available to you to cover the costs of your treatments and other damages. Contact our Patient Advocates today to review your case. We can put you in touch with top mesothelioma lawyers who will work your behalf to get you the compensation you deserve.

View Author and Sources

  1. Medscape general Medicine, “Peritoneal Mesothelioma: A Review” Retrieved from: Accessed on December 20, 2017.
  2. Claire F. Verschraegen, Charles R. Key, and Raffit Hassan, “Clinical Presentation and Natural History of Mesothelioma: Abdominal” Retrieved from: Accessed on December 20, 2017.

Last modified: May 7, 2018