Testicles

What is Testicular Cancer

Testicular cancer is rare and accounts for 5% of all cancer cases among men. Unlike other tumors, such as prostate cancer, testicular cancer is more common in the younger population, between 15 and 50 years of age.

It is also known as germ cell tumor (GCT) – benign or malignant neoplasms derived from germ cells, which give rise to sperm cells (in men) and eggs (in women).

Subtypes of testicular cancer

The testicles are composed of many types of cells, and each of them can develop one or more types of cancer. It is important to know the type of cell in which the cancer started and what type of tumor was developed because this determines the treatment and helps predict the prognosis.

• Germ cell tumors – more than 90% of testicular cancers begin in cells known as germ cells, which produce sperm. The main types of germ cell tumors (GCT) in the testicles are seminomas and non-seminomas. Many testicular cancers contain both seminoma and non-seminoma cells. These mixed tumors are treated as non-seminomas because they grow and spread like non-seminomas.
• Seminomatous tumors – seminomas tend to grow and spread more slowly than non-seminomas. The two main subtypes of these tumors are classical (or typical) seminomas and spermatocytic seminomas. More than 95% of seminomas are classical. They usually occur in men between 25 and 45 years old. Spermatocytic seminoma is rare and tends to occur in older men (on average, at age 65).
• Non-seminomatous tumors – this type of testicular cancer occurs in men between late adolescence and early 30s. There are four main types of non-seminoma tumors: embryonal carcinoma, yolk sac carcinoma, choriocarcinoma, and teratoma. Most tumors are a mixture of different types, but this does not change the treatment for most non-seminomatous cancers. They account for 60% of all testicular tumors.

Each subtype of non-seminomatous tumor can express proteins that enter the bloodstream and are useful not only for its diagnosis but also for prognosis and monitoring. These proteins are called tumor markers.

• Carcinoma in situ – Testicular cancers can start as a non-invasive form of the disease called carcinoma in situ. This type of cancer does not always progress to an invasive type. It is difficult to diagnose because it does not cause symptoms and often does not form a mass that can be felt.
• Stromal tumors – These develop in the tissues that produce hormones and in the supportive tissues of the testicles. They account for less than 5% of testicular tumors, but up to 20% of childhood testicular tumors. There are two main subtypes: Leydig cell tumors, which are usually benign and develop in the cells that produce male sex hormones, and Sertoli cell tumors, which develop from the cells that support and nourish the germ cells that produce sperm. They are usually benign, but if they spread, they tend not to respond to chemotherapy and radiation therapy.
• Secondary testicular cancer – This type starts in another organ and spreads to the testicle. It is treated focusing on the organ of origin. Lymphoma is the most common secondary testicular cancer and occurs more frequently than primary testicular tumors in men over 50 years old. Prognosis depends on the type and stage of the lymphoma.

Symptoms and signs of testicular cancer

The most common sign of testicular cancer is the development of a hard lump that sometimes causes pain, but in most cases, it does not. Patients may also feel the testicle enlarging and experience a heaviness or abdominal pain.

Other symptoms that should be noted include:

• Increased or decreased testicle size;
• Hardening;
• Vague pain in the lower abdomen;
• Blood in the urine;
• Nipple tenderness (rare); and
• Early puberty, with growth of facial and body hair before expected.

Diagnosis of testicular cancer

One of the difficulties in detecting the tumor in young men is that it can be confused or even masked by orchid epididymitis – inflammation of the testicles and epididymis, tubes located behind the testicles that collect and carry sperm. Orchid epididymitis is sexually transmitted.

The first phase of diagnosing a testicular tumor is through a clinical examination, checking for palpable nodules or changes suggestive of cancer. One of the tests for diagnostic confirmation is scrotal ultrasound, which identifies homogeneous lesions (suggestive of seminomatous tumors) or heterogeneous lesions (indicative of non-seminomatous tumors).

Laboratory tests are also performed to identify tumor markers (alpha-fetoprotein, beta-HCG, and LDH).

Once the diagnosis is confirmed, it is necessary to define the clinical management – this is when a computed tomography (CT) scan of the chest, abdomen, and pelvis is essential. It allows for the staging of the disease and the definition of post-orchiectomy therapeutic management – removal of the testicle to control cancer.

Treatment for testicular cancer

The treatment of testicular tumors is based on staging, histological type, and risk classification. Each stage of the disease requires a different approach. The main available therapeutic alternatives are:

• Partial orchiectomy – surgical procedure in which one or both testicles are removed through a small incision in the scrotum. It should be indicated in tumors smaller than 2 cm in the absence of contralateral testicle or severe functional deficit due to high risk of local recurrence; and
• Radical orchiectomy – this surgical procedure, even when performed alone, cures most patients. In this surgical technique, the incision is made in the abdominal region, not in the scrotum. Testicular prosthesis implantation can be performed in the same surgery.
• Chemotherapy – there are several chemotherapy regimens described for the treatment of testicular cancer. Because it is a systemic treatment, administered intravenously, it has more side effects because it also affects healthy cells; and
• Radiotherapy – radiotherapy is reserved for seminomatous tumors, as they are more sensitive to this therapy. The application is indicated in localized tumors (Stage I) and low-volume retroperitoneal tumors (Stages II a and b).

The choice of therapies to be used alone or in combination depends on the stage of cancer, as described below.

Stage I (except IS), seminoma and non-seminoma – patients present with disease localized or restricted to the testicle and spermatic cord. The risk of metastasis is about 20% – that is, cure is achieved in 80% of cases with radical orchiectomy alone.

Stage II A or B, non-seminoma – in patients with non-seminomatous tumors, limited retroperitoneal disease (<5cm), and normal tumor markers, there are two treatment options with a good prognosis. The most commonly used strategy is initial chemotherapy followed by surgical intervention. This combination is associated with high cure rates, and as it is a systemic treatment method, the incidence of distant metastases is also reduced.

Stage II A or B, seminoma – in this case, an alternative to chemotherapy is radiation therapy at higher doses than those administered for stage I, also with a good prognosis.

Stage II C, III, and IS, seminoma and non-seminoma – the cure rate for patients with testicular tumor and metastatic disease of large volume can reach 90%, depending on the risk classification. The reason for the success of the therapy is the development of chemotherapy regimens based on cisplatin. The number of cycles will depend on the risk classification. Three cycles may be performed in patients with a good prognosis, or four in patients with intermediate and poor prognoses.

Prevention of testicular cancer

There is no known way to prevent testicular cancer. However, early detection through self-examination is crucial, as it greatly increases the chances of cure. It is recommended to perform self-examination once a month, after a warm bath. The warm water relaxes the scrotum and makes it easier to detect any changes in size, sensitivity, or abnormalities.