Metastatic testicular cancer

Dr Daleen Geldenhuys describes how testicular cancer becomes metastatic and the treatment thereof.

Testicular germ cell tumours, broadly classified into seminomas and non-seminomas, are among the most curable cancers, with five-year survival rates of approximately 95%.

Men with advanced disease are classified into good-, intermediate-, and poor-risk groups. The grouping considers the site of the primary cancer as well as the sites of metastatic disease, and serum tumour marker levels. 

The primary cancer can be testicular or in the chest. This may sound strange, but it’s thought to be attributed to an abnormal migration of gonadal tissue (cells that are destined to become part of the testes) during embryogenesis (developing baby). 

Stage 4 risk groups

Poor-risk disease would include a chest origin as opposed to a testicular origin, metastases to organs other than lungs and lymph nodes, such as brain or liver, and very high tumour markers at diagnosis. These markers include alpha fetoprotein (aFP) and beta Human chorionic gonadotrophin (BHCG).

Good- and intermediate-risk groups are patients with lower blood markers, mainly lung metastases and primary tumours that don’t involve the chest.

Early stage spread predictable

The pattern of spread for men diagnosed with early stage testicular cancer is predictable. Men with clinical Stage 1 disease generally relapse in the retroperitoneum (behind the abdominal organs), and chest metastases in the absence of retroperitoneal disease are unusual, particularly for pure seminomas. 

Men whose prior treatment included chemotherapy often present with more widely-spread disease. In multiple studies evaluating second-line treatment, over 60% of patients have retroperitoneal disease, 40 to 50% have lung metastases, 26 to 32% have mediastinal node involvement, 10 to 20% have liver metastases, and 2 to 11% have bone involvement.

Brain metastases

Central nervous system (brain) metastases occur in approximately 1% of men with metastatic germ cell cancer at the time of diagnosis, and between 0,4 and 4% subsequently develop brain metastases. 

Brain metastases almost always occur in the setting of concurrent or prior disseminated disease and are associated with a poor prognosis. Brain metastases are more common with choriocarcinoma (variant of non-seminomatous testicular cancer), and these metastases tend to bleed both spontaneously and during treatment with chemotherapy.

The diagnosis of relapsed disease is made by an increase in serum tumour markers or evidence of disease progression on radiographic studies, physical examination, and patient symptomatology.

Treatment options

The main option for patients with Stage 4 disease is chemotherapy. 

A single brain metastasis can be surgically removed or treated with stereotactic radiation (Gamma Knife). Multiple brain metastases need whole brain radiation. 

Occasionally, when there is limited active disease after a course of chemotherapy, or even limited lung metastases, surgical removal of lymph nodes is an option to ensure long-term survival and even cure.

Patients who have relapsed after their initial therapy can often be salvaged and remain disease-free with second or subsequent lines of therapy. However, subsequent lines of therapy are associated with significantly increased toxicity in long-term survivors.

In special circumstances, an autologous bone marrow transplant can be an option for relapsed disease. The bone marrow of the patient is harvested and stored, and this allows for bigger doses of chemotherapy to be given. The bone marrow is then given back to the patient a few days later to reconstitute the patient’s own bone marrow and hopefully long-term survival.

It’s very important to pay attention to your body and to seek medical advice if you have any lump, ongoing pain, shortness of breath or unexplained weight loss. This can happen to men of any age, regardless if any of the well-known risk factors were present before: an undescended testis or a family history of testicular cancer.

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