What Are the Most Common Diseases Misdiagnosed as Mesothelioma?

Mesothelioma is a rare cancer that forms in the lining of the lungs, abdominal cavity, heart and testes. These linings, which are composed of tissue and fluid, can be infiltrated by sharp asbestos fibers and irritated, causing tissue to turn cancerous.

However, cancers forming in other parts of the body can spread to these linings, which can lead to mistakes in the diagnostic process.

There are approximately 3,000 cases of mesothelioma diagnosed in the U.S. each year. That number has been dropping for a few years, and some cases are not actually mesothelioma.

A study published in the Annals of Diagnostic Pathology reviewed more than 4,000 cases of mesothelioma and identified 311 that were misdiagnosed. Mesothelioma misdiagnosis – or misdiagnosis for any illness – causes errors in patients’ treatment plans and the prognosis they receive. It is critical to get a second opinion from a specialist if you were diagnosed with mesothelioma by a general oncologist.

The cancers and other health conditions misdiagnosed as mesothelioma were:

• Metastatic carcinoma to the pleura (lining of the lungs) or peritoneum (lining of the abdomen)
• Primary lung cancer
• Other cancers arising from or near serosal membranes
• Fibrous pleurisy

 

Reasons for Misdiagnosis of Mesothelioma

Researchers said there were several common errors among the misdiagnosed cases. One was “failure to consider important radiographic information regarding the gross distribution of tumor,” meaning the doctors did not notice or consider tumors outside of the mesothelial linings.

Two other errors were “lack of awareness of consideration of another malignancy” and “overreliance on certain immunohistochemical results.” Lastly, some doctors failed to perform certain diagnostic studies.

Here’s more information about each of the diseases misdiagnosed as mesothelioma.

 

Metastatic Carcinoma to the Pleura or Peritoneum

Metastatic carcinoma to the pleura or peritoneum is a case where the tumors have spread to either of these linings (the pleura lines the lungs; the peritoneum lines the abdominal cavity). There were 129 cases of metastatic carcinoma misdiagnosed as mesothelioma.

Lung carcinomas accounted for the most (73). Carcinomas are a type of cancer that forms in epithelial tissue, which lines most of your organs, the internal passageways in your body (like your esophagus), and your skin. Most cancers that affect organs such as the lungs or pancreas are carcinomas.

 

Primary Lung Cancer

Primary lung cancer refers to lung cancer that has not metastasized to the pleura or peritoneum. There were 111 cases of primary lung cancer misdiagnosed as mesothelioma. Doctors noticed tumors on or near the lungs and misdiagnosed the disease as mesothelioma.

Pleural mesothelioma (a type of mesothelioma in the pleura) forms near the lungs, and it’s common to misdiagnose lung cancer as pleural mesothelioma or vice versa.

 

Other Cancers Arising From or Near Serosal Membranes

Serosal membranes are linings of organs and cavities such as the lungs, heart and abdominal cavity. Mesothelioma can arise from serous membranes, but there are other serous membranes in the body, such as linings of the ovaries. 

There were 33 misdiagnosed mesothelioma cases in this category. 

Another possibility is types of cancers forming near serous membranes. An example is malignant endothelial neoplasms. This type of cancer comes from endothelial cells, which form a cell layer that lines all blood vessels and regulates exchanges between the bloodstream and surrounding tissues. One study found 14 cases of endothelial cell cancer closely resembling mesothelioma.

 

Fibrous Pleurisy

Fibrous pleurisy, also called pleural fibrosis, is a noncancerous condition defined by thickening and stiffening of the pleura. This condition is a result of pleural inflammation or exposure to asbestos, which can irritate the pleural lining and cause thickening.

There were 38 cases of fibrous pleurisy (also called pleural fibrosis) misdiagnosed as mesothelioma.

Pleural thickening is a symptom of pleural mesothelioma, and doctors sometimes misdiagnose this symptom as cancer.

If you have been diagnosed with mesothelioma, connect with our patient advocate and registered nurse Karen Ritter. She can connect you with top mesothelioma specialists to help you receive the best treatment possible. Karen can also put you in contact with a specialist to offer a second opinion on your mesothelioma diagnosis. Email Karen at karen@mesotheliomaguide.com to learn more.