Written By: Devin Golden

Pleural Mesothelioma Diagnosis

A pleural mesothelioma diagnosis is only given by a medical professional – usually a doctor or cancer specialist – at a hospital or cancer center. There are specific steps doctors follow in diagnosing pleural mesothelioma.

Karen Ritter, RN BSN

Medically Reviewed By

Karen Ritter, RN BSN

Registered Nurse

Karen Ritter, RN BSN

Medically Reviewed By

Karen Ritter, RN BSN

Registered Nurse


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Important Facts About How Pleural Mesothelioma Is Diagnosed

  • Diagnosing pleural mesothelioma involves imaging tests (X-ray, CT scan, and MRI scan) and a biopsy.
  • The only definitive way to diagnose pleural mesothelioma is with a tissue biopsy. There are a few techniques that can be used to obtain tissue biopsies from the chest cavity.
  • Doctors often use a systematic approach called differential diagnosis when determining a mesothelioma diagnosis. It involves compiling a list of conditions that present similar symptoms.

How Is Pleural Mesothelioma Diagnosed?

The final pleural mesothelioma diagnosis test — the only way to get a definitive diagnosis — is a tissue biopsy. During a pleural mesothelioma tissue biopsy, doctors remove a piece of tissue and send it to a pathologist for evaluation.

What Is the Pleura? Icon

What Is the Pleura?

The pleura is a thin lining around your lung cavity where pleural mesothelioma forms. This very thin lining is made up of tissue and fluid, and its job is to be a buffer between the lungs and your chest wall. The pleura allows for the lungs to expand and contract as needed.

The cells in the pleura are called mesothelial cells. The pleura is part of your body’s mesothelium, which are a set of protective linings around specific organs and organ cavities.

Mesothelioma Differential Diagnosis Icon

Mesothelioma Differential Diagnosis

The challenge of diagnosing mesothelioma is it can act like many other health conditions. This is called a mesothelioma differential diagnosis: when mesothelioma can mimic or have the same symptoms of other diseases. Doctors usually compile a list of possible causes and diseases based around the symptoms. This list is the mesothelioma differential diagnosis, and it helps doctors determine which tests to perform.

The pleural mesothelioma diagnosis steps and additional testing should help differentiate between mesothelioma and other conditions.

Some conditions to consider in the differential diagnosis of pleural mesothelioma are:

  • Non-small-cell lung cancer
  • Benign asbestos-related pleural disease
  • Pleural sarcomas and lymphomas
  • Pleural fibrosis
  • Pleural effusions
  • Pulmonary tuberculosis

Steps to Get a Pleural Mesothelioma Diagnosis

The steps to getting a pleural mesothelioma diagnosis involve recognizing symptoms of pleural mesothelioma, visiting a doctor and getting multiple tests. The steps may change depending on which tests you or your loved one receives, but the steps of getting a pleural mesothelioma diagnosis usually are as follows:


Meet with your primary physician to discuss symptoms.


Get a chest X-ray to look for abnormalities.


Get a computed tomography (CT) scan for a three-dimensional view of your chest cavity.


Get an MRI scan for detailed images of the chest.


Get a biopsy to test tissue samples.

Pleural Mesothelioma Diagnosis Testing

There are a few different imaging scans and biopsy tests that may be used as part of pleural mesothelioma diagnosis testing. We’ve listed them below to help you understand the process of a diagnosis:

Diagnosis Testing Options

X-Ray Icon


Provides a two-dimensional image to show any signs of a tumor, mass or fluid buildup near the lungs

CT Scan Icon

CT Scan

Provides three-dimensional images of the chest cavity and pleura

PET Scan Icon

PET Scan

Sends radioactive sugar into the blood for cancerous cells to absorb while a special camera sends a picture of the radioactive energy back to the medical team for real-time footage

MRI Icon

MRI Scan

Creates detailed images of soft tissue to help locate any abnormalities or tumors

Biopsies Icon


Removes a tissue or fluid sample from the pleural cavity to examine under a microscope. A tissue biopsy is the only way to get a definitive diagnosis of pleural mesothelioma

Types of Biopsies for Pleural Mesothelioma Diagnosis

There are a few different types of biopsies used to diagnose pleural mesothelioma. These biopsies are split into two groups: tissue biopsies and fluid biopsies. Tissue biopsies are the only way to get a true diagnosis of mesothelioma, but require a slightly more invasive approach.

The procedures used to obtain tissue biopsies for a pleural mesothelioma diagnosis are:

  • Thoracotomy – Traditional biopsy technique to obtain tissue from the chest cavity by making an incision in the chest
  • Thoracoscopy – An alternative, less-invasive chest biopsy procedure, where doctors make a small incision in the skin and deep tissue and then insert a small tube with a camera attached to remove tissue samples
  • Mediastinoscopy – Examines the mediastinum, which is the space in the middle of the chest between the lungs, and allows the doctor to remove lymph nodes and tissue samples to help determine whether pleural mesothelioma has spread

Non-surgical biopsies involve removing fluid from the chest cavity to test for evidence of pleural mesothelioma cancer cells. Doctors use a needle to extract fluid. Another term for this is mesothelioma pleural fluid analysis.

Diagnosing the Pleural Mesothelioma Stages

Part of diagnosing pleural mesothelioma cancer is determining the stage. This is an important part of the diagnosis process since the stage of pleural mesothelioma impacts the prognosis and treatment options.

Some people ask, “What stage is malignant pleural mesothelioma?” The truth is there are four stages of pleural mesothelioma. Stage 1 is the earliest form of the cancer, meaning it has not yet spread to nearby organs or grown thick. Stage 4 is the latest form of pleural mesothelioma, meaning it has spread to distant areas of the body.

Symptoms are often different depending on the pleural mesothelioma stage. For instance, stage 1 usually has fewer and less severe symptoms of mesothelioma. Stage 4 has the most severe symptoms.

Frequently Asked Questions About Pleural Mesothelioma Diagnosis

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What Are the Tests for a Pleural Mesothelioma Diagnosis?

The main tests used for a pleural mesothelioma diagnosis are imaging scans and a tissue biopsy. People who suspect they may have pleural mesothelioma cancer need to see their physician for a detailed evaluation, chest X-ray, followed by a CT scan and an MRI scan, if indicated. If there’s enough evidence of the cancer, then doctors will recommend a tissue biopsy. These are the most likely steps to pleural mesothelioma diagnosis testing.

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What Biopsies Are Used for a Pleural Mesothelioma Diagnosis?

The three tissue biopsy procedures for a pleural mesothelioma diagnosis are thoracotomy, thoracoscopy and mediastinoscopy. These all involve making an incision in the patient’s chest and removing a sample of tissue to test for pleural mesothelioma. Another biopsy technique involves removing fluid from the chest and sending it for a mesothelioma pleural fluid analysis. This is less conclusive than a tissue biopsy.

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Are Mesothelial Cells Normal in Pleural Fluid?

Yes. Mesothelial cells are normal in pleural fluid. The pleura is a thin lining around the lungs. It serves as a protective barrier between the lungs and chest wall. The pleura has two tissue linings, which are made of mesothelial cells. In between the tissue linings is fluid (pleural fluid), so it’s normal for mesothelial cells to be found in pleural fluid.

Sources & Author

  1. Tests for Malignant Mesothelioma. American Cancer Society. Retrieved from: https://www.cancer.org/cancer/malignant-mesothelioma/detection-diagnosis-staging/how-diagnosed.html. Accessed: 04/10/19.
  2. Types of biopsies used to look for cancer. American Cancer Society. Retrieved from: https://www.cancer.org/treatment/understanding-your-diagnosis/tests/testing-biopsy-and-cytology-specimens-for-cancer/biopsy-types.html. Accessed: 04/10/19.
Devin Golden

About the Writer, Devin Golden

Devin Golden is a content writer for Mesothelioma Guide. He produces mesothelioma-related content on various mediums, including the Mesothelioma Guide website and social media channels. Devin's objective is to translate complex information regarding mesothelioma into informative, easily absorbable content to help patients and their loved ones.