What is a Teratoma: Find out if it is really your twin!

Many of us have heard about a case or two where the person says something along the lines of, “The doctors pulled out the tumor… It was made of hair and even had some teeth in it! Seems I ate my twin in the womb!” Well, that hairy, toothy tumor is known as a teratoma. So, what is a teratoma? What are the symptoms, causes, diagnosis, and treatment for a teratoma? Is a teratoma your twin? How does a teratoma affect the brain? What are some tips to cope with a teratoma? Spoiler alert: a teratoma isn’t your twin that you ate in the womb- read on to find out what is a teratoma!

Contrary to popular belief, a teratoma isn’t your twin that you are in the womb.

What is a teratoma?

A teratoma is a rare type of tumor that is made up of developed organs and tissues such as bone, teeth, muscle, and hair. They are most commonly seen in the testicles, ovaries, and tailbone, but they can be seen elsewhere in the body, too. They can happen to newborns, children, and adults alike. However, they are overall more common in females.

Teratoma is from the Greek word teratos, meaning monstrous tumor. Rightly named so considering that way back when people didn’t know what these hairballs of teeth and muscles were. The earliest known reference to a teratoma comes from a clay tablet (located now in the Chaldean Royal Library of Nineveh) dating back to between 600 B.C. and 900 B.C. Pathologists and physicians alike have been fascinated with teratomas throughout the centuries because they often believed the tumor to be a sign of the devil. They were first recognized to be within the embryoid nature in 1636 when scientists discovered a growth that contained a human skull and pigmented optic cups. That said, it wasn’t until 1856 that these odd, abnormal growths were recognized to be different from other tumors.

Is a teratoma your twin?

There is a type of teratoma that appears and looks like a malformed fetus. This is called a fetus in fetu (fetus within a fetus) and occurs in roughly 1 out of every 500,000 people. Although the teratoma may look like a fetus, a baby can’t survive without the amniotic sac. There are a couple of theories to go along with this type of tumor. First, the fetus in fetu is a highly developed dermoid cyst. The second theory states that the teratoma is simply the remains of a twin that was unable to develop in the womb. The fetus in fetu is often found at a young age and can happen to either boys or girls. 90% of the cases are found before 18 months old. Most of the fetuses found to lack a brain structure. However, 82.5% have limb buds and 91% have a spinal column. A fetus in fetu can only happen if the twins both share the same placenta (a phenomena known as monochorionic) and that have their own amniotic fluid sac (known as diamniotic). However, this is a rare one.

Some people are under the impression that their teratoma (that isn’t a fetus in fetu) is their dead twin- perhaps eaten or mixed together in the womb. However, that’s not accurate- a teratoma is not your dead twin. While it has many components that a normal body would have, such as teeth and hair, it never was another person. The difference between a teratoma and a twin is that a twin occurs when a fertilized egg divides in two, and a teratoma occurs when one’s own germ cells multiply abnormally and become normal tissue in an abnormal place (such as hair and teeth in the ovaries).

What is a teratoma- Types

There are two main types: immature or mature. An immature teratoma is more likely to develop into a malignant and dangerous cancer. A mature teratoma is often not cancerous (benign) but can grow back once removed. There are three types of mature ones. The first is a cystic mature teratoma, also known as a dermoid cyst, which means that it’s enclosed in this own fluid-containing sac. The second type is a solid mature teratoma which is made up of real tissue but isn’t self-enclosed like the cystic type. The third type is a mixed mature teratoma which contains both cystic and solid parts.

Furthermore, they occur most often in three specific areas- the tailbone, the ovaries, and the testicles. However, they can be rarely found elsewhere in the body, too. The tailbone teratoma, also known as a sacrococcygeal teratoma, is a type that can grow outside of the body, but also inside in the tailbone area. It’s the most common type found in newborns and children, but it’s still overall rare to find. It happens in roughly 1 out of every 35,000 to 40,000 infants and children. That said, it’s more common in girls than boys. According to a 2015 study in Thailand between 2998 and 2012, for every boy that had a sacrococcygeal, four girls had it, too (4-1 ratio).

An ovarian teratoma is incredibly painful because it causes a condition known as ovarian torsion– the twisting of the ovaries due to the growing inside. It was found in one recent study that with little girls who have an ovarian teratoma, it’s possible to spare their ovaries (not take them out) while taking out the mass. In some cases, the ovarian teratoma can come with a rare condition known as NMDA encephalitis– a condition that produces extreme headaches and cognitive issues such as psychosis and confusion.

A testicular teratoma is most common between ages 20 and 30, but it can happen at any age. It’s often found due to a lump or swelling in the testicles. According to a large study, more cases of benign (non-cancerous) testicular teratomas are found in adult men than little boys.

What is a teratoma- Symptoms

If the tumor is small, the symptoms are minimal and in the beginning, there are no symptoms at all. However, when they start to develop, the symptoms begin to differ depending on where the teratoma is located in the body. The common, general signs and symptoms include:

• Bleeding
• Swelling
• Pain
• Slightly elevated levels of the hormone beta human chorionic gonadotropin (BhCG).
• Slightly elevated levels of a marker for tumor known as alpha-ferroprotein (AFP)

As previously mentioned, the symptoms differ from the different types of teratomas and where they are located. For the tailbone, the common symptoms include:

• A visible mass since it can grow outside the body as well as inside.
• Leg weakness.
• Abdominal pain and constipation.
• Swelling in the pubic region
• Painful urination

With an ovarian teratoma, the biggest symptom experienced will be intense pain in the abdomen region or pelvis due to ovarian torsion (twisting pressure on the ovaries) which is caused by the growing mass.

A testicular teratoma will have one big symptom- swelling or a lump in the testicle. That said, there are some cases in which it showed no symptoms at all. It is a type that grows quickly and doesn’t present any symptoms in the beginning. Both the malignant (cancerous) and benign testicular ones often cause testicular pain.

What is a teratoma- Causes

It is caused by a complication in the body’s growth process which involves the way in which your cells are able to specialize and differentiate from each other. These special tumors come from the body’s germ cells, a kind known as pluripotent, which begin production very early in the development of a fetus. Some of the earliest germ bells become the sperm or egg-producing cells. However, they can also be found in other parts of the body such as the mediastinum (the membrane that separates the lungs) and the tailbone.

The most widely accepted theory today is known as the parthenogenic theory which states that teratomas arise and originate from these primordial cells. The theory can explain why teratomas can be found with human parts such as wax, teeth, hair, and sometimes an almost-formed fetus. The theory also explains why it shows up in the same place that the primitive germ cells go (the ovaries, testicles, and tailbone).

How does a teratoma affect the brain?

Ovarian ones have gotten quite a bit of hype lately because it’s been discovered that they can actually mess with our brains and we don’t even know it. Some women were misdiagnosed and sent to hospitals and care units due to odd behavior and metabolic breakdowns. It was later discovered that these women had a benign ovarian teratoma. These women’s teratomas not only contained the typical teeth and hair but also contained brain tissue. Their bodies saw the teratoma as a type of foreign tissue and tried to “mount an attack” against it by using an immune response against the brain cells that were found in the tumors. However, the immunological system was tricked and not only attacked the brain tissue in the tumor, but also tried to attack the brain tissue in the women’s actual brains which is why they were acting so strangely.  

CogniFit Brain Training: Trains and strengthens essential cognitive abilities in an optimal and professional way.

Well, there is another rare type of teratomas that is found in the brain, too. Occurring in only 0.3-3.4% of all intracranial tumors, a 57-year-old male one complained of ataxia, vision changes, incontinence, and a change in mental status within one weeks time. The tests done on him showed a large intrasellar mass with a suprasellar extension that involved the ventricular system. He had the mass removed and it was found to be a mature cystic teratoma. The man also had radiotherapy done afterward to treat the cancer cells. After 4 years, his vision was good as new.

What is a teratoma – Diagnosis

For a sacrococcygeal teratoma, it can probably be detected in an ultrasound scan of the fetus and found before birth. Another way to diagnose it is to find swelling at the tailbone of the fetus which is something that doctors look for in newborns. Doctors may also use CT scans, blood tests, and X-rays of the pelvis to help diagnose. This type must be closely monitored. According to a study, there is a high chance of regrowth within three years of the teratoma being removed.

For an ovarian teratoma, the best diagnosis is to pay attention to the ovarian torsion which causes insane pain in the pelvic or abdominal area. The dermoid cysts (mature ovarian teratomas) often don’t present any symptoms which make it hard to diagnose. This type of teratoma is often found during routine gynecologic visits and examinations.

Testicular teratomas are often discovered by accident during an exanimation. The doctor will examine the testicles for atrophy and will feel for a firm mass which can be a sign of cancerous, malignant teratomas. Blood tests are also used to look for the elevated levels of the hormones AFT and BhCG. Ultrasounds can also help to look at the progress is making (how big it’s getting and how quickly). If the teratoma is cancerous, the doctor will need to check if it has spread to other parts of the body by doing X-rays to the abdomen and chest areas.

What is a teratoma- Treatment

When it is found in the womb, it’s done so by using an ultrasound

A sacrococcygeal teratoma (tailbone), if in the fetal stage, will be monitored by the doctor closely during pregnancy. If the tumor is small, a vaginal delivery is okay. If it becomes enlarged or there is excess amniotic fluid, a C-section is probably necessary. In some rare cases, fetal surgery is necessary to take of the teratoma before birth. If the tumor is cancerous, chemotherapy is often used alongside a surgical removal of the teratoma.

An ovarian teratoma is often removed via a laparoscopic surgery. That is, if the cyst remains small. A laparoscopic surgery is a surgery that makes a small incision in the abdomen to insert a scope and small curring tool. It’s minimally invasive. There is some danger to removing an ovarian teratoma with a laparoscopic surgery because if the cyst becomes punctured, it can leak a waxy material which causes an inflammatory response known as chemical peritonitis. In other cases, it’s necessary to remove the whole ovary (however, the second ovary will take over the job and continue to menstruate and ovulate). However, 25% of the time, the ovarian cyst is found in both ovaries. The cancerous, immature ovarian teratomas are usually found in girls in their early 20s and are curable with a combination of surgery and chemotherapy.

The testicular teratomas are often taken care of by surgical removal. However, when it’s cancerous, teratomas don’t often respond well to chemotherapy. The testicle will also probably be removed completely to ensure there is no spreading to other parts of the body.

What is a teratoma- Tips to cope

• Be sure to go to your doctor if you feel that you might have a one or are in extreme pain.
• Understand that it is not your dead twin, it’s simply cells that formed and were put together in an odd, human-like way.
• Get a support group if it is cancerous. There are many support groups out there.
• Join a clinical study! There are tons of clinical studies being done. The more we can know about them, the more we can help treat them better.

Let us know what you think in the comments below!

Anna Bohren

Anna is a freelance writer who is passionate about translation, psychology, and how the world works.