Malignant teratoma is a type of cancer made of cysts that contain one or more of the three layers of cells found in a developing baby (embryo). These layers are called ectoderms, mesoderms, and endoderms.

Dermoid cyst - malignant; Nonseminomatous germ cell tumor - teratoma; Immature teratoma

Malignant teratoma occurs most often in young men in their 20s - 30s. It is often located in the chest area. Most malignant teratomas can spread throughout the body, and have spread by the time of diagnosis.

A number of other cancers are often associated with these tumors, including:

• Acute myelogenous leukemia (AML)
• Embryonal rhabdomyosarcoma
• Malignant histiocytosis
• Myelodysplasia (MDS)
• Small cell undifferentiated carcinoma

Symptoms include:

• Chest pain or pressure
• Cough
• Fatigue
• Limited ability to tolerate exercise
• Shortness of breath

The health care provider will perform a physical exam, which may reveal blockage of veins entering the center of the chest due to increased pressure in the chest area. 

The following tests help diagnose the tumor:

• Chest x-ray
• CT scans of the chest, abdomen, and pelvis
• Blood tests to check beta-HCG and alpha fetoprotein (AFP) levels
• Mediastinoscopy with biopsy

Chemotherapy is used to treat the tumor. A combination of medicines (usually cisplatin, etoposide, and bleomycin) is commonly used.

After chemotherapy is complete, CT scans are taken again to see if any mass remains. Surgery may be recommended if there is a possibility that the cancer will grow back in that area.

There are many support groups available for people with cancer. Contact the American Cancer Society -- www.cancer.org

The outlook depends on the tumor size and location and the age of the patient.

The cancer can spread throughout the body and there may be complications of surgery or related to chemotherapy.

Call your health care provider if you have symptoms of malignant teratoma.

McColl FD. Diseases of the diaphragm, chest wall, pleura, and mediastinum. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 99.