What Is Testicular Mesothelioma?

Testicular Mesothelioma Tumors

Mesothelioma is an aggressive and rare cancer that forms in the mesothelium throughout several areas of the body. A tumor can form in tissue with a mesothelial membrane, including the lining of the lungs, stomach, thoracic cavity, and testes.

The most common site of mesothelioma is in the pleural lining of the chest, followed by the lining of the abdomen and chest cavity. Testicular mesothelioma, the rarest site, occurs when tumors develop in the mesothelium covering areas of the testes, including the tunica vaginalis, epididymis, sporadic cord, or tunica albuginea. 

When mesothelioma tumors form, patients can experience a swollen testicle and fluid buildup in the scrotum. Symptoms first occur while a mass of tissue builds up in the testicle, known as thickening of the tunica vaginalis tissue.

During the tissue buildup process, an abnormal rate of cell growth occurs. The body attempts to counteract the process with inflammation and fluid buildup, which can cause further malignant cell growth. Testicular mesothelioma tumors are hard to diagnose. The swelling and formation of masses are often mistaken for more common conditions or diseases.

Testicular Mesothelioma Causes and Symptoms

Testicular mesothelioma occurs in male patients of varying ages, but most commonly in men between the ages of 55 and 75 years old. Researchers still do not know the mechanisms by which testicular mesothelioma develops. Exposure to asbestos, however, is a commonly linked risk factor. Other risk factors include trauma, long-term hydrocele, and herniorrhaphy.

In rare cases, patients with this site of mesothelioma are younger than 55 and exhibit no risk factor or known history of asbestos exposure. Researchers are currently studying more causes of testicular mesothelioma.

The common misdiagnosis of the disease happens because its symptoms appear in other types of testicular cancers and medical issues. The most common symptom of this disease is the formation of a fluid-like sac around the testes, called a hydrocele. Often, patients do not experience pain with a hydrocele. Since testicular mesothelioma spreads quickly,  doctors recommend performing regular checks for abnormalities.

Diagnosing and Treating Testicular Mesothelioma

Diagnosing testicular mesothelioma caused by asbestos can be challenging and may require a specialist. First, a patient with symptoms undergoes a physical examination followed by radiography to detect any lesions that could indicate an underlying disease. Medical ultrasound is very accurate in detecting testicular tumors. 

Doctors will not officially confirm a definitive diagnosis until performing a biopsy. The biopsy process involves removing tissue from the tumor detective on the ultrasound. The tissue sample gets sent to the lab for testing. The doctor evaluates the results from the biopsy to determine if the patient has mesothelioma.

Treatment of testicular mesothelioma typically starts with surgery to remove the tumor and affected tissue. Patients in later stages may undergo a multi-modal treatment involving a combination of surgery, chemotherapy, and immunotherapy. 

After surgery, patients in earlier stages typically undergo radiation therapy followed by chemotherapy. Common chemotherapy drugs for testicular mesothelioma treatment following surgery include cisplatin and pemetrexed. Both drugs are designed to help prevent disease recurrence.

Survival Rates and Life Expectancy

Life expectancy provides an estimated amount of time a patient is likely to live after a mesothelioma diagnosis.  Although this type of mesothelioma is extremely rare, the life expectancy is better than in other sites. In one study of 113 testicular mesothelioma patients, the 5-year overall survival rate was between 49% and 58%. By comparison, the average survival rate for mesothelioma, in general, is typically between 4-18 months after diagnosis.

Survival rates reflect the percentage of people with the same type and stage of cancer who survive for a specified amount of time after their diagnosis. In the same study, researchers reported the 10-year overall survival was between 33% and 45%. Patients in later stages of cancer had significantly less survival time compared with those with stage I or stage II.