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Yolk Sac or Germ Cell Tumor

What is a Yolk Sac or Germ Cell Tumor?

A yolk sac tumor is a rare, malignant tumor of cells that line the yolk sac of the embryo.

These cells normally become ovaries or testes; however, the cause of a yolk sac tumor is unknown. It is most often found in children before the ages of 1 to 2, but can occur throughout life.

The term germ cell tumors encompasses many types of tumors some are malignant and others are benign. These include tumors, teratomas, embryonal carcinoma, dysgerminomas, semenoma, etc. These tumors can occur in the testes, ovaries, chest, brain and other parts of the body.

Signs and Symptoms of a Germ Cell Tumor

Signs and symptoms depend on the tumor location.

Within the testes, the tumor is a visible, painless, firm swelling or may lead to precocious puberty.

In the ovary it is not as visible and the tumor may grow very large before being noticed. This can lead to abdominal pain, abdominal swelling. Other symptoms can lead to abnormal vaginal bleeding or precocious puberty.

In the sacrococcygeal area, it may be seen as a swelling of the buttocks often mistaken for a bruise or infection. Tumors in the chest can present with chest pain, cough or shortness of breath.

Diagnosis of a Germ Cell Tumor

These cancer cells secrete specific hormones, two of which are alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG).

A blood test which shows an increase in either of these can help with the diagnosis. Your doctor may also check for an elevated LDH (lactate dehydrogenase). Other studies may include an ultrasound, CT scan, or MRI. A biopsy will be needed for final diagnosis. The biopsy, surgical removal of part of the mass is done in surgery under general anesthesia so the child is not conscious and will not feel any pain.

Germ cell tumors can be diagnosed in utero.

Sacrococcygeal teratomas are the most common germ cell tumor of childhood and the most frequently recognized neoplasm of the fetus.

Stages of a Germ Cell Tumor

The staging depends on whether the tumor is in only one place or if it has spread to other parts of the body.

Treatment of a Germ Cell Tumor

Treatment decisions are made depending on the stage and location of the tumor.

Surgery is the most effective treatment, if the tumor is in one location.

The need for chemotherapy and radiation depends on tumor type, location and spread of tumor.

Timing of chemotherapy and amount of chemotherapy will be decided by your physician.

Long-Term Outlook

Prognosis for germ cell tumors varies greatly depending on multiple factors, including type of tumor, child’s age, tumor location, and staging. In general, those with higher stage tumors are at risk for poorer outcomes.

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Last Updated 09/2022

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Children and young adults with tumors of the brain and spine receive advanced, comprehensive care at the Brain Tumor Center.

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