Types of Testicular Cancer

November 22, 2024

This page was reviewed under our medical and editorial policy by Alexander Chehrazi-Raffle, M.D., assistant professor, Department of Medical Oncology & Therapeutics Research, City of Hope^® Cancer Center Duarte 

The testicles comprise many types of cells, each of which may develop into one or more forms of testicular cancer. More than 90% of testicular cancers start in germ cells, which are the cells that make sperm.

The main types of germ cell tumors are seminomas and non-seminomas.

This guide to testicular cancer types will provide more information for patients and their loved ones.

Seminoma

Seminoma is a type of testicular cancer that tends to grow and spread slowly, though it sometimes spreads to the lymph nodes. Seminomas originate in male germ cells — cells that play a role in sperm creation. For a testicular cancer to be classified as a seminoma, all of the cancer cells within the tumor must consist of 100% germ cells.

Seminomas have long been divided into two subtypes, classical and spermatocytic. However, with more information available today, spermatocytic tumors have been newly categorized into a more distinct grouping.

Classical seminoma: The germ cells in this subtype have not matured or specialized into their role yet. Accounting for 95% of cases, most seminomas are of the classical type. This subtype is most common in men in their mid-20s to mid-40s.

• Seminomas are diagnosed with a range of medical tests, including a physical examination, ultrasounds and blood testing. Blood tests look for tumor markers, which are high levels of certain types of protein, including alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG). Seminoma cancer types may have increased hCG amounts, but they never have increased AFP. A biopsy is not usually performed with testicular cancer, as it could cause the cancer to spread.
• Surgery is the most common treatment for seminoma. Oftentimes, this is a radical orchiectomy, which removes the tumor and the testicle. The treatment plan depends on the cancer’s stage and may include a period of active surveillance, then radiation therapy and chemotherapy when needed. Seminomas are known to respond well to chemotherapy, which may be given after surgery to reduce the chance of the cancer returning.

Non-seminoma

Non-seminomas are tumors that form in sperm cells. They are more common in younger men, from their teens to mid-30s. Non-seminomas are divided into four subtypes: embryonal, yolk sac carcinoma, choriocarcinoma and teratoma. They are more common than seminomas and also tend to be faster-growing. Non-seminoma cancers may also include more than one subtype.

Embryonal carcinoma tends to occur most often in younger and middle-aged men. Its cells are undeveloped and stem from very early (embryonic) stage cells. This subtype is known to spread quickly and may move beyond the testicle to other areas of the body.

Embryonal carcinomas are diagnosed with a range of medical tests, including a physical examination, imaging and blood testing. During tumor marker testing, embryonal carcinoma tends to show increased levels of both AFP and beta-human chorionic gonadotropin (beta-hCG). protein types. Embryonal carcinoma treatment may vary, depending on the cancer’s stage. This tumor type is typically treated with surgery to remove the testicle and/or chemotherapy treatment.

Yolk sac carcinoma is the most common type of testicular cancer in infants and children. It is rare in adults. The cells in this cancer subtype look like the yolk sac of a human embryo and are also early-stage cells. This cancer type is generally known to respond well to treatment, particularly in children.

Several medical tests, including physical examination, imaging and blood testing, are used to diagnose yolk sac carcinomas. In tumor marker testing, this cancer often has high levels of AFP. However, AFP levels may not appear elevated if the cancer has a small amount of yolk sac carcinoma cells and larger numbers of other cell types. Yolk sac carcinoma treatment may vary, depending on the age of the patient and the stage of their cancer. It typically includes surgery, specifically a radical inguinal orchiectomy, and it may also involve removal of nearby lymph nodes. Chemotherapy is also part of comprehensive treatment for this subtype.

Choriocarcinoma of the testicle is most commonly found in adults. It is fast-growing and often spreads to other areas of the body, including the bones, lungs and brain. For this reason, it is often diagnosed after it has spread outside the testicle. It is very rare.

Choriocarcinomas are diagnosed with a range of medical tests, including physical examination, imaging tests and blood testing. Tests for choriocarcinoma tumor markers tend to show very high levels of hCG proteins. Choriocarcinoma treatment often involves surgery to remove the testicle, followed by chemotherapy.

Teratoma, in its pure form, is rare. This tumor type more often occurs in a mix of non-seminoma tumors and resembles the tissue layers of a developing embryo under a microscope. Teratomas are categorized into three types: mature teratoma, immature teratoma and teratomas with somatic-type malignancy.

Teratomas are diagnosed with a range of medical tests, including physical examination, imaging tests and blood tests. Teratomas often show normal levels during tumor marker testing, but sometimes increased levels of AFP are found. Teratoma treatment may vary, depending on the cancer’s stage. A radical orchiectomy, with possible lymph node removal, is the most commonly used treatment. Chemotherapy is often a part of treatment, but not all teratomas respond to this treatment. Radiation therapy may sometimes be used.

Intratubular Germ Cell Neoplasia

Intratubular germ cell neoplasia is a precancerous type of testicular tumor, also known as carcinoma in situ or Stage 0 testicular cancer. However, it does not always go on to become cancer. Carcinoma in situ occurs when abnormal cells develop in tubular structures within the testicles that produce sperm cells.

Because it does not cause symptoms, intratubular germ cell neoplasia is diagnosed via biopsy. It is likely to be closely monitored with regular doctor’s visits, blood tests and imaging. If doctors suspect it might be progressing into an invasive cancer, surgery and radiation therapy are the most common treatment options.

Spermatocytic Tumor

Spermatocytic tumors grow from more mature, postpuberty germ cells and are mostly considered benign (not cancerous), though the tumor tends to be larger than classical seminoma tumors. The spermatocytic type more commonly occurs in older men. This slower-growing tumor rarely spreads to other areas of the body. Standard treatment for this tumor is surgery to remove the testicle (orchiectomy).

Stromal Tumors

Stromal tumors are rare, most often seen in children, and they are usually not cancerous. They are divided into two subtypes: Leydig cell tumors and Sertoli cell tumors. Both types originate in testicular cells that produce hormones. Together, they account for less than 5% of adult tumors within the testicles but 20% in children.

Leydig cell tumors originate in Leydig cells, which produce testosterone. This subtype does not usually spread beyond the testicles, although it may. These tumor types are most often found in men between 30 and 60 years of age.

Diagnosis is made using a variety of tests, including physical examination, imaging and tumor marker testing. Tests for tumor markers look for elevated levels of AFP, as well as lactate dehydrogenase (LDH) and beta-hCG. Treatment options vary, depending on the tumor’s stage, but may include surgical removal of the testicles, removal of lymph nodes and chemotherapy.

Sertoli cell tumors begin in the Sertoli cells, which play a key role in sperm production. Diagnosis is made through physical examination and imaging tests.

Treatment options vary, depending on the tumor’s stage, but may include surgical removal of the testicle, testis-sparing surgery, removal of lymph nodes and chemotherapy.

Cancers That Metastasize to the Testicle

In some cases, testicular cancer may be a secondary type of cancer. This means the cancer began somewhere else in the body and later spread into the testicles.

The most common cancers that metastasize to the testicles are lymphoma and leukemia, although this may also occur with other cancers, including prostate, skin, kidney and lung cancers. Lymphoma and leukemia testicular cancers may be treated with surgery, radiation therapy and chemotherapy.

When testicular cancer occurs as a result of lymphoma, it is more often seen in men 50 years of age and older.