Peritoneal Mesothelioma Diagnosis

Quick Summary

Peritoneal mesothelioma is a rare diagnosis that can only be made by experienced gastrointestinal specialists with a background in peritoneal mesothelioma research and treatment. It’s crucial for patients to receive an accurate diagnosis so that they can receive potentially life-saving peritoneal mesothelioma treatments.

Peritoneal Mesothelioma Diagnosis Overview

If you suspect you have symptoms of peritoneal mesothelioma and you have been exposed to asbestos in the past, then it’s vital to see a top peritoneal mesothelioma specialist.

Here is what everyone with peritoneal mesothelioma needs to know about diagnosing this rare disease:

  • Peritoneal mesothelioma can only be diagnosed by an experienced specialist
  • Specialists diagnose peritoneal by cell type and determine whether it’s early or advanced stage
  • A peritoneal mesothelioma diagnosis needs to be accurate as it informs a patient’s treatment plan
  • Doctors use image scans, blood tests, and tissue samples to help diagnose peritoneal mesothelioma
  • The only conclusive way to diagnose peritoneal mesothelioma is through a biopsy, which tests tissue samples from the abdomen
  • Common misdiagnoses with peritoneal mesothelioma include irritable bowel syndrome (IBS), hernias or other cancer types like ovarian
  • Patients are encouraged and within their right to seek a second opinion from another peritoneal mesothelioma specialist to confirm their diagnosis and receive new treatment options

How Peritoneal Mesothelioma is Diagnosed

Peritoneal mesothelioma is a complex disease that acts differently from other cancers. Tumors grow in irregular shapes and can quickly spread to distant sites and deep tissues within the abdomen. Even when doctors do identify the condition as malignant, it can be difficult to know the primary location of the tumor, which is the place where it first formed. Without adequate experience, an oncologist can easily mistake peritoneal mesothelioma for other abdominal malignancies that affect the peritoneum surface.

Peritoneal Mesothelioma Diagnosis Update

Because there are so many parties working together on a diagnosis, the process can take several weeks or months to complete. One publication showed that the median time from symptoms to diagnosis was 122 days. Doctors often need to rule out other more common conditions before they can reach peritoneal mesothelioma diagnosis.

Here are the steps involved in diagnosing peritoneal mesothelioma:

  1. Physical examination
  2. Image tests
  3. Blood and biomarker tests
  4. Biopsies

1. Physical Examination

When patients first develop peritoneal mesothelioma symptoms, they report them to their general practitioner. Usually, by the time patients notice symptoms, the condition is already quite advanced, making an early diagnosis of peritoneal mesothelioma difficult. The most common early peritoneal symptoms patients reports are abdominal pain and abdominal swelling. Patients may be inexplicably losing weight and report anorexia as a symptom as well.

Doctors examine their patients based on the symptoms they report. For peritoneal mesothelioma symptoms, doctors will tap on your abdomen and see if this results in acute pain or any other signs. Using a stethoscope, doctors can also listen for peritoneal fluid buildup (ascites), which is a key indicator of mesothelioma.

Patients should report their history of asbestos exposure to their doctor. Describing details such as when and how you used asbestos products can help doctors piece together the overall picture of your condition.

2. Image Tests

Imaging tests are a crucial step in helping doctors diagnose your condition. Scans allow doctors to see inside your abdomen and look for fluid buildup and tumor masses. Different types of tests show different things and they are all helpful in showing doctors the location and extent of the mesothelioma.

Common tests used in diagnosing peritoneal mesothelioma include:

  • Abdomen X-Ray: X-ray images were taken of the abdomen give doctors a 2D look at any abnormalities, such as ascites (Fluid buildup) or peritoneal thickening. Depending on how advanced the condition is, x-rays may also show masses of tissue, which can indicate a malignant (cancerous) tumor.
  • CT Scan: Because x-rays only show doctors a 2D view of the abdomen, they may also order CT (computed tomography) scans to get a series of images taken across the abdomen. With more detailed images, doctors can see if tumor masses have spread and to where which helps them identify the best locations for biopsy samples.
  • MRI: MRIs (magnetic resonance imaging) uses magnetic waves to take pictures of your soft tissues to reveal any abnormal masses. Like CT scans, MRIs can help doctors see the extent of the disease and show them where to pull tissue samples from for testing.

All patients going through this diagnostic process should be aware that imaging scans alone cannot diagnose mesothelioma. Imaging scans are tools doctors use to find abnormalities, but they cannot tell doctors whether you have cancer or what type you have.

3. Blood and Biomarker Tests

With ongoing research into peritoneal mesothelioma, doctors continue to identify unique biomarkers—substances within the patient—that can indicate a possible likelihood of mesothelioma.

One biomarker called soluble mesothelin-related peptides (SMRP) has elevated levels in 84% of mesothelioma cases. Using the MesoMark® test—which tests for high SMRP levels—doctors can determine a possible presence of mesothelioma cells.

Currently, doctors also look at many other proteins and substances that could indicate mesothelioma. But none of these tests are reliable enough yet to use as a conclusive diagnostic or screening tool for peritoneal mesothelioma.

4. Biopsies

Currently, the only way for doctors to diagnose peritoneal mesothelioma conclusively is through biopsy. A biopsy is a process of removing tissue or fluid from the abdomen to test it for cancer cells.

A few biopsy techniques can be used when diagnosing peritoneal mesothelioma:

  • Paracentesis: Doctors can test for mesothelioma by withdrawing fluid from the peritoneum. Using a small, hollow needle, doctors collect and drain peritoneal fluid into a catheter and test it for mesothelioma cancer cells.
  • Laparoscopy: Using a laparoscope—a tiny camera inserted into the abdomen—doctors can see peritoneal tissues. By withdrawing samples of these tissues, doctors can test them for cancer cells.
  • Laparotomy: When doctors open up the abdomen to remove tissues, it’s called a laparotomy. By conducting open surgery to the abdomen, doctors can also have a closer look at the extent of the disease.

Histology and Cytology for Peritoneal Mesothelioma

Histology and cytology are two fields that study diseases. Histology looks at diseased tissues while cytology looks at diseased fluid. It can be difficult for doctors to identify mesothelioma from cytologic tests because the fluid may contain low, undetectable levels of cancer cells.

Tumor biopsies are much more effective and can conclusively show mesothelioma cells. By looking at tissues under a microscope, histopathologists can identify whether the tumor is composed of epithelioid, sarcomatoid or mixed mesothelioma cell type—a key factor in receiving the right treatments.

Common Peritoneal Mesothelioma Misdiagnoses

Peritoneal mesothelioma is frequently misdiagnosed because it is so rare and remains unknown in the broader medical community. Even experienced general oncologists can misidentify this type of malignancy. This is both because of the vague symptoms, like abdominal pain, and because mesothelioma cells can be mistaken for other types of cancer cells.

Some of the possible misdiagnoses that peritoneal mesothelioma patients can receive include:

  • Irritable bowel syndrome
  • Hernias
  • Intestinal or stomach cancers
  • Ovarian cancer in women

In the event that doctors do diagnose your condition as peritoneal mesothelioma, it’s still possible to receive a misdiagnosis in cell type or stage. Patients with biphasic (mixed) tumors may only be diagnosed as having one cell type if samples weren’t collected from multiple parts of the tumor.

Though there is no official staging system for peritoneal mesothelioma, patients may be told that their condition is either more or less advanced than it actually is. Only peritoneal mesothelioma specialists with extensive experience treating this disease can properly stage your condition.

Second Opinions From Peritoneal Mesothelioma Specialists

All patients are encouraged to seek the second opinion of a highly experienced peritoneal mesothelioma specialist to confirm your cell type and stage.

Some of the top peritoneal mesothelioma specialists available for consultation with include:

If you’ve been diagnosed with peritoneal mesothelioma or you are experiencing symptoms, then contact Mesothelioma Help Now today. Our Patient Advocates can answer your questions and advise you on next steps after your diagnosis.

View Author and Sources

  1. MedGen Medicine: “Peritoneal Mesothelioma: a review.” Retrieved from: Accessed on December 28, 2017.
  2. American Cancer Society, “How is Malignant Mesothelioma Diagnosed?” Retrieved from: Accessed on December 28, 2017.

Last modified: May 7, 2018