Benign Occurrences Of Mesothelioma

Contrary to popular belief, mesothelioma is not always malignant or cancerous.

In some cases, though rare, patients have been diagnosed with a benign form of mesothelioma. The mechanisms and causes behind these forms of mesothelioma are not understood, but it is treatable with surgery. Success rates with surgical removal are highly encouraging.

The benign form of mesothelioma is not asbestos-related, like the more well-known malignant mesothelioma. The malignant forms usually have a latency period of around 20 to 50 years after exposure before they begin to show evidence of mesothelioma, but the benign forms can occur at any age since they are not linked to asbestos exposure.

Just like malignant mesothelioma, there are several types of benign mesothelioma as well and each is more rare than its malignant cousins. Some are so rare, that there are only a handful of documented cases that have ever occurred. For example, benign multicystic peritoneal mesothelioma has only been reported 153 times in all of medical literature and a variety called well-differentiated papillary mesothelioma has been encountered less than 60 times in all of written history.

Another difference between benign and malignant mesothelioma is the survival rate. Malignant mesothelioma has a very high mortality rate, meaning most people will die of causes related to the illness. Benign mesothelioma, on the other hand, has an incredibly high rate of effective treatment and recovery, with full recovery being possible for most diagnosed cases. There have been cases, however, where the tumors have come back and on relapse they are malignant. This is one of the reasons that doctors will monitor patients closely for possible new tumors.

Benign versus Malignant

Tumors, whether they are malignant or benign, form when otherwise healthy cells begin to divide and multiply too quickly, leading to a lump of matter.

It is important to keep in mind that benign tumors are not considered “cancerous” and that the term cancer is reserved for malignant tumors specifically.

One of the key differences between the two types of tumors is their tendency to move or spread throughout the body. Benign tumors will not spread or metastasize and they will not invade nearby tissues, organs, or systems. This is the main reason benign tumors are considered much less serious, even though they can still cause other issues. It is also why these benign tumors are more responsive to surgery.

Types Of Benign Mesothelioma

There are a number of different types of mesothelioma that are benign, often delineated by physical cell characteristics. These tumors are frequently easy to treat and the prognosis is often encouraging. 

Types of benign tumors include:

  • Well-Differentiated Papillary Mesothelioma
    • Mostly benign, but have been encountered as a malignant variety
    • Most common in the abdominal cavity of 30-40-year-old women
    • Can occur in the heart sac, pleura, and testicular lining
  • Benign Multicystic Peritoneal Mesothelioma
    • Begins in the peritoneal cavity
    • More common in women, though it does happen in men and children as well
    • Most common symptoms include abdominal pain and swelling
    • Most likely variety to become malignant on relapse
  • Adenomatoid Tumor
    • Common on the testicular lining