Testicular Mesothelioma

Causes

Unlike mesothelioma, a cancer that can easily be traced to asbestos exposure, doctors do not yet understand how asbestos exposure can cause a primary tumor to develop on the tunica vaginalis, the pouch of serous membrane that covers the testes.

It appears as firm, white-yellow nodules on the surface of the tunica vaginalis. The nodules can eventually encase the contents of the scrotum and cause the membrane to thicken.

Local trauma and inflammation also may play a role in its development. Some cases present without any identifiable risk factors.

Prognosis and Survival Rate for Testicular Mesothelioma

Men with this cancer have a significantly better prognosis than most people with other types of mesothelioma.

Nearly 49% of patients survive five years after diagnosis, and 33% survive 10 years, according to a 2019 study published in the journal Urology.

Patients with the biphasic cell type of the cancer were associated with worse overall survival compared to other mesotheliomas and the epithelioid subtypes.

Of the 113 testicular mesothelioma patients in the study, 75% of cases had the epithelioid cell type. Older patients and those with tumors greater than or equal to 4 centimeters in size were associated with a worse survival.

Quick Fact:

Testicular mesothelioma is a clinically aggressive type of cancer, which means it can spread rapidly. The testicular type tends to recur within a few years, even in cases where tumors are surgically removed.

Symptoms and Diagnosis

There is no set of symptoms unique to testicular mesothelioma cancer. Many people with this cancer initially receive the wrong diagnosis because doctors mistake it for a more common condition such as a hernia.

The most common testicular mesothelioma symptom is a hydrocele, a buildup of fluid in the scrotum.

More than half of the patients in the 2019 Urology study had a hydrocele. About one-third of patients had a painless scrotal mass.

Because it is so rare and doesn’t present unique symptoms, testicular mesothelioma is often diagnosed during or after surgery.

The definitive way of confirming a cancer diagnosis is to perform a biopsy. This involves removing a tissue sample from the tumor and sending it to the lab for testing.

Evaluating the sample with a technique called immunohistochemical staining helps doctors determine if the patient has testicular mesothelioma or another disease.

Treatment for Testicular Mesothelioma

The most common treatment for testicular mesothelioma is surgery. Nearly all of the 113 testicular mesothelioma patients (98.2%) in the 2019 study underwent surgical resection of the tumor.

This procedure removes the affected testicle and the entire spermatic chord. If the cancer has spread to nearby lymph nodes, doctors will remove them as well with a surgery called lymphadenectomy.

Surgery may be followed by chemotherapy with cisplatin and pemetrexed, the longstanding standard-of-care treatment for mesothelioma. Doctors may offer radiation therapy next to kill any remaining cancer cells and prevent the cancer from returning.

Only 5.3% of patients received radiation therapy in the 2019 study. Researchers could not determine if adjuvant therapy has an impact on overall survival, given such a small cohort.

In some cases, testicular mesothelioma is a secondary tumor, with the primary tumor located within the peritoneum (the membrane that lines the abdominal cavity). For situations like this, doctors have to treat the patient for peritoneal mesothelioma as well.