Testicular Tumor Markers: What are They and Why do They Matter?

Many cancer types have tumor markers that are specific to them. What exactly is meant by tumor marker? Tumor markers are substances which are detectable in the blood in quantities higher than what would normally be in circulation. These substances can range from proteins, amino acids, hormones, and enzymes. Although they can’t by officially used to diagnose cancer by themselves, they can play many important roles in the assessment and treatment of cancer.

 

Testicular cancer has 3 commonly used tumor markers: AFP, hCG and LDH. These tumor markers may or may not be elevated depending on the type of testicular cancer. Detailed information on most types may be found here.

Alpha-Fetoprotein (AFP)

As the name suggests, AFP is a protein that has a role during fetal development. It’s role in adults is uncertain but continues to be present at detectable levels. AFP is important in testicular cancer because it can be used to distinguish between the two major subtypes of testicular cancer: pure seminoma and nonseminoma. These subtypes have different prognoses and treatments, so it is very important information to have when managing testicular cancer. Ultimately, the tumor subtype is determined by the pathologist evaluating the cells under the microscope in conjunction with other special tests. However, AFP continues to be important for one big reason: seminoma testicular cancer doesn’t produce AFP.

What does this mean? It means that even if pathology shows a seminoma testicular cancer, if the AFP is elevated, it is not a pure seminoma and can’t be treated as such. If AFP is detectable, there are nonseminoma cells present somewhere, even if they weren’t apparent with the pathological review.

Human Chorionic Gonadotropin (hCG)

hCG is probably best known for its role in pregnancy.

It is normally produced by cells within the placenta and rises during pregnancy. It is the common hormone used in pregnancy tests, including home pregnancy tests as well as blood tests done at the doctor’s office. Testicular cancer cells are also able to produce hCG and may be seen in both major subtypes of cancer. hCG is known for having the potential to cause increased breast tissue growth in men known as gynecomastia, which can, therefore, be a sign of testicular cancer.

Lactate Dehydrogenase (LDH)

LDH is the least specific of the tumor markers. In other words, there are many processes, aside from testicular cancer, that can cause it to be elevated. For example, both liver disease and red blood cell destruction will cause it to be high. It can be elevated in both main subtypes of testicular cancer. Check here for more information about LDH.

Application and Significance of the Tumor Markers

The tumor markers have different purposes throughout the course of diagnosis, treatment, and followup.

 In diagnosis, they can help to distinguish between seminoma and nonseminoma testicular cancers. If the tumor markers remain elevated following surgical removal of the cancerous testicle, it can indicate residual cancer in other locations and chemotherapy, additional surgery or radiation therapy may be indicated. After treatment, elevated tumor markers may be the first sign of a recurrence of cancer, especially in nonseminoma cancers.

It is to be remembered that tumor markers by themselves are seldom of much value. They need to be considered along with other data such as signs, symptoms and imaging studies, such as CT scans. Tumor markers need to be expertly interpreted in the correct context of a host of factors. This is best done by oncology professionals including medical oncologists, urologists, and radiation oncologists.

Please check here to learn more about the basics of testicular cancer.

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