Overview

Testicular cancer begins when normal cells in a testicle begin to change and grow uncontrollably, forming a mass called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). Testicular cancer is almost always curable if found early and is often curable even when at an advanced stage.

The testicles are part of the male reproductive system. Each man has two testicles, and they are located under the penis in a sac-like pouch called the scrotum. They can also be called testes or gonads. The testicles produce sperm and testosterone, a hormone which plays a role in the development of the reproductive organs and other male characteristics.

Most types of testicular cancer develop in the sperm-producing cells known as germ cells, and are referred to as germ cell tumors. Germ cell tumors most commonly start in the testicles but can also develop in other parts of the body, such as the retroperitoneum (the back of the abdomen near the spine), the mediastinum (the central portion of the chest between the lungs), the lower spine, and very rarely, the pineal gland (a small gland in the brain).

There are two different categories of germ cell tumors that occur in the testicles: seminoma and non-seminoma. Generally, seminoma is relatively slow growing, while non-seminoma tends to grow and metastasize (spread) more quickly.

Teratoma is a unique type of non-seminoma. Unlike the other types of germ cell tumors, it is not very sensitive to chemotherapy. The primary treatment for teratoma is to remove it with surgery. Although a teratoma is less likely to spread, it needs to be removed because it can become a much more dangerous cancer if left in place.

This section provides information only on germ cell tumors (seminoma and non-seminoma) of the testicles. Other, less common types of testicular tumors include Leydig cell tumor, Sertoli cell tumor, and carcinomas of the rete testis. These can often be successfully treated by surgically removing the affected tissue; however, if they spread to other areas of the body, they are more difficult to treat. Other types of cancer, such as lymphoma and leukemia, occasionally spread to the testicles. To find out more about cancer that started in another part of the body and spread to the testicles, read about that specific type of cancer.

Statistics

In 2009, an estimated 8,400 men in the United States will be diagnosed with testicular cancer. It is estimated that 380 deaths from this disease will occur this year. The deaths are from cancer that has spread to other parts of the body and could not be effectively treated with chemotherapy, radiation therapy, and/or surgery.

The overall five-year relative survival rate of people with testicular cancer is 96%. What this means is that, within the first five years after diagnosis, a man’s risk of dying from testicular cancer is about 4%. This number includes all men diagnosed with testicular cancer. The survival rate is higher for men diagnosed with early-stage cancer and lower for men with later-stage cancer. For men with cancer that shows no evidence of having spread beyond the testicles (Stage 1; see Staging), the survival rate is about 99%. For men with cancer that has spread to the back of the abdomen (Stage 2), the survival rate is about 96% but depends on the size and number of tumors.

For patients with more widely spread cancer (Stage 3), the survival rate is about 71% overall but for men with advanced stage cancer, the disease is classified into one of three categories - good risk, intermediate risk, and poor risk - to better predict a man’s prognosis (chance of recovery). For men in the good-risk advanced-stage group, the five-year survival rate is 94%. Men in the intermediate-risk group have a five-year relative survival rate of 83%, and men in the poor-risk group have a five-year relative survival rate of 71%. Testicular cancer may be more difficult to treat if it has spread to the liver, bones, or brain, but even in those cases, men can often be cured.

Cancer survival statistics should be interpreted with caution. These estimates are based on data from thousands of cases of this type of cancer in the United States each year, but the actual risk for a particular individual may differ. It is not possible to tell a man how long he will live with testicular cancer. Because the survival statistics are measured in five-year intervals, they may not represent recent advances made in the treatment or diagnosis of this cancer.

Statistics adapted from the American Cancer Society's publication, Cancer Facts & Figures 2009.

Find out more about basic cancer terms used in this section.