Teratomas maybe found in babies, children, and adults. Teratomas of embryonal origin are most often found in babies at birth, in young children, and, since the advent of ultrasound imaging, in fetuses.

The most commonly diagnosed fetal teratomas are sacrococcygeal teratoma (Altman types I, II, and III) and cervical (neck) teratoma. Because these teratomas project from the fetal body into the surrounding amniotic fluid, they can be seen during routine prenatal ultrasound exams. Teratomas within the fetal body are less easily seen with ultrasound; for these, MRI of the pregnant uterus is more informative.

A teratoma is a tumor made up of several different types of tissue, such as hair, muscle, or bone. They typically form in the ovaries, testicles, or tailbone and less commonly in other areas. Symptoms may be minimal if the tumor is small. A testicular teratoma may present as a painless lump. Complications may include ovarian torsion, testicular torsion, or hydrops fetalis.

They are a type of germ cell tumor (a tumor that begins in the cells that give rise to sperm or eggs). They are divided into two types mature and immature. Mature teratomas include dermoid cysts and are generally benign. Immature teratomas may be cancerous. Most ovarian teratomas are mature. In adults, testicular teratomas are generally cancerous. Definitive diagnosis is based on a tissue biopsy.

Treatment of tailbone, testicular, and ovarian teratomas is generally by surgery. Testicular and immature ovarian teratomas are also frequently treated with chemotherapy.

Teratomas occur in the tailbone in about 1 in 30,000 newborns making them the most common tumor in this age group. Females are affected more often than males. Ovarian teratomas represent about a quarter of ovarian tumors and are typically noticed during middle age. Testicular teratomas represent almost half of testicular cancers. They can occur in both children and adults. The term comes from the Greek words for "monster" and "tumor".

Neurocutaneous melanosis is associated with the presence of either giant congenital melanocytic nevi or non-giant nevi of the skin. It is estimated that neurocutaneous melanosis is present in 2% to 45% of patients with giant congenital melanocytic nevi. Patients with non-giant congenital melanocytic nevi seem to have a much lower, but undefined risk. Of these patients, only a small number are symptomatic, usually displaying symptoms before the age of 2.

These symptoms are the result of melanocytic lesions being present in the leptomeninges of the central nervous system.

Symptoms can include:

- Papilledema

- Cranial palsies

- Headache

- Vomiting

- Seizures

Others symptoms may also exist that are related to an increase in intracranial pressure. These symptoms seem to be present regardless of the malignancy of the melanin deposits within the central nervous system.

Approximately 10% of patient with neurocutaneous melanosis also present the Dandy–Walker syndrome and associated Dandy-Walker malformation. This malformation involves an enlargement of the posterior fossae and fourth ventricle along with agenesis of the cerebellar vermis. The abnormalities of the leptomeninges during fetal development due to neurocutaneous melanosis may be the cause of this increased incidence of the Dandy-Walker malformation. The development of hydrocephalus is the most common symptom associated with a combination of neurocutaneous melanosis and a Dandy-Walker malformation, occurring in about two out of three patients.

SCT is seen in 1 in every 35,000 live births, and is the most common tumor presenting in newborn humans. Most SCTs are found in babies and children, but SCTs have been reported in adults and the increasingly routine use of prenatal ultrasound exams has dramatically increased the number of diagnosed SCTs presenting in fetuses. Like other teratomas, an SCT can grow very large. Unlike other teratomas, an SCT sometimes grows larger than the rest of the fetus.

Sacrococcygeal teratomas are the most common type of germ cell tumors (both benign and malignant) diagnosed in neonates, infants, and children younger than 4 years. SCTs occur more often in girls than in boys; ratios of 3:1 to 4:1 have been reported.

Historically, sacrococcygeal teratomas present in 2 clinical patterns related to the child’s age, tumor location, and likelihood of tumor malignancy. With the advent of routine prenatal ultrasound examinations, a third clinical pattern is emerging.

- Fetal tumors present during prenatal ultrasound exams, with or without maternal symptoms. SCTs found during routine exams tend to be small and partly or entirely external. The internal SCTs are not easily seen via ultrasound, unless they are large enough to reveal their presence by the abnormal position of the fetal urinary bladder and other organs, but large fetal SCTs frequently produce maternal complications which necessitate non-routine, investigative ultrasounds.

- Neonatal tumors present at birth protruding from the sacral site and are usually mature or immature teratomas.

- Among infants and young children, the tumor presents as a palpable mass in the sacropelvic region compressing the bladder or rectum. These pelvic tumors have a greater likelihood of being malignant. An early survey found that the rate of tumor malignancy was 48% for girls and 67% for boys older than 2 months at the time of sacrococcygeal tumor diagnosis, compared with a malignant tumor incidence of 7% for girls and 10% for boys younger than 2 months at the time of diagnosis. The pelvic site of the primary tumor has been reported to be an adverse prognostic factor, most likely caused by a higher rate of incomplete resection.

- In older children and adults, the tumor may be mistaken for a pilonidal sinus, or it may be found during a rectal exam or other evaluation.

Symptoms are assessed on a case by case basis. Some cysts in the CNS can be asymptomatic (producing or showing no symptoms), depending on their location in the brain or spinal cord. If the cysts develop in critical areas of the central nervous system, they can present one or more of the following symptoms:

- Pressure in the spinal cord or brain

- Rupture of nerves around the cyst

- Weakness in specific parts of the body controlled by the cyst-infected brain region

- Inflammation

- Hydrocephalus

- Brainstem hemorrhage

- Seizures

- Visual disturbances and hearing Loss

- Headache

- Difficulty with balance or walking

In general, symptoms vary depending on the type of cyst and its location within the CNS.

Neurocutaneous melanosis is a congenital disorder characterized by the presence of congenital melanocytic nevi on the skin and melanocytic tumors in the leptomeninges of the central nervous system. These lesions may occur in the amygdala, cerebellum, cerebrum, pons, and spinal cord of patients. Although typically asymptomatic, malignancy occurs in the form of leptomeningeal melanoma in over half of patients. Regardless of the presence of malignancy, patients with symptomatic neurocutaneous melanosis generally have a poor prognosis with few treatment options. The pathogenesis of neurocutaneous melanosis is believed to be related to the abnormal postzygotic development of melanoblasts and mutations of the NRAS gene.

An immature teratoma is a rare type of malignant (cancerous) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs).

Like a mature teratoma, it contains several different types of tissue such as hair, muscle, and bone. Unlike a mature teratoma, it contains primitive neuroepithelium.

This category of cysts takes over areas of necrotic tissue in the brain from injuries, diseases, or abnormalities, which occur due to the central nervous system's nonregenerative nature. These cysts can affect all germ layers of the CNS, but are most common in the arachnoid mater, and the ventricular space, which may block CSF pathways. These cysts can be static (stationary) or progressive. Some examples of cysts originating from the CNS tissue include:

- Arachnoid cysts (Leptomeningeal cysts)

- Ependymal cysts

- Cystic cerebellar astrocytomas

- Colloid cysts

Sacrococcygeal teratoma (SCT) is a type of tumor known as a teratoma that develops at the base of the coccyx (tailbone) and is thought to be derived from the primitive streak. Sacrococcygeal teratomas are benign 75% of the time, malignant 12% of the time, and the remainder are considered "immature teratomas" that share benign and malignant features. Benign sacrococcygeal teratomas are more likely to develop in younger children who are less than 5 months old, and older children are more likely to develop malignant sacrococcygeal teratomas. The Currarino triad (OMIM 176450), due to an autosomal dominant mutation in the MNX1 gene, consists of a presacral mass (usually a mature teratoma or anterior meningocele), anorectal malformation and sacral dysgenesis.

Source:

- severe headache

- visual loss (due to papilledema)

- vomiting

- bilateral Babinski sign

- drowsiness (after several hours of the above symptoms)

- gait change (rotation of feet when walking)

- impaction/constipation

- back flexibility

Ectomesenchymoma is a rare, fast-growing tumor of the nervous system or soft tissue that occurs mainly in children, although cases have been reported in patients up to age 60. Ectomesenchymomas may form in the head and neck, abdomen, perineum, scrotum, or limbs. Also called malignant ectomesenchymoma.

Malignant ectomesenchymoma (MEM) is a rare tumor of soft tissues or the CNS, which is composed of both neuroectodermal elements [represented by ganglion cells and/or well-differentiated or poorly differentiated neuroblastic cells such as ganglioneuroma, ganglioneuroblastoma, neuroblastoma, peripheral primitive neuroectodermal tumors – PNET] and one or more mesenchymal neoplastic elements, usually rhabdomyosarcoma . The most accepted theory suggests that this tumor arises from remnants of migratory neural crest cells and thus from the ectomesenchyme.

A ganglioneuroma is typically asymptomatic, and is typically only discovered when being examined or treated for another condition. Any symptoms will depend upon the tumor's location and the nearby organs affected.

For example, a tumor in the chest area may cause breathing difficulty, chest pain, and trachea compression. If the tumor is located lower in the abdomen, it may cause abdominal pain and bloating. A tumor near the spinal cord may cause spinal deformity or spinal compression, leading to pain and loss of muscle control or sensation in the legs and/or arms.

These tumors may produce certain hormones, which can cause diarrhea, an enlarged clitoris (in females), high blood pressure, increased body hair, and sweating.

The tumor largely affects children under 15 years of age and about 20% only are found in adults with nearly 60% involving males and 40% females (1). The most frequent locations are head and neck (orbit and nasopharynx), central nervous system, abdomen and retroperitoneum, pelvis, perineum, scrotum and prostate(1). Clinical symptoms are not specific and usually caused by local tumor compression and infiltration.

Hemangioblastomas (or haemangioblastomas, see spelling differences) (capilliary hemangioblastomas) are tumors of the central nervous system that originate from the vascular system usually during middle-age. Sometimes these tumors occur in other sites such as the spinal cord and retina. They may be associated with other diseases such as polycythemia (increased blood cell count), pancreatic cysts and Von Hippel-Lindau syndrome (VHL syndrome). Hemangioblastomas are most commonly composed of stromal cells in small blood vessels and usually occur in the cerebellum, brain stem or spinal cord. They are classed as grade one tumors under the World Health Organization's classification system.

The skin lesions evolve through characteristic stages:

1. blistering (from birth to about four months of age),

2. a wart-like rash (for several months),

3. swirling macular hyperpigmentation (from about six months of age into adulthood), followed by

4. linear hypopigmentation.

Alopecia, hypodontia, abnormal tooth shape, and dystrophic nails are observed. Some patients have retinal vascular abnormalities predisposing to retinal detachment in early childhood. Cognitive delays/mental retardation are occasionally seen.

Discolored skin is caused by excessive deposits of melanin (normal skin pigment).

Most newborns with IP will develop discolored skin within the first two weeks.

The pigmentation involves the trunk and extremities, is slate-grey, blue or brown, and is distributed in irregular marbled or wavy lines.

The discoloration sometimes fades with age.

Neurological problems can include: cerebral atrophy, the formation of small cavities in the central white matter of the brain, and the loss of neurons in the cerebellar cortex.

About 20% of children with IP will have slow motor development, muscle weakness in one or both sides of the body, mental retardation, and seizures.

They are also likely to have visual problems, which can include: crossed eyes, cataracts, and severe visual loss.

Dental problems are common, and include missing or peg-shaped teeth - patients with IP often keep milk teeth into adult life.

Breast anomalies can occur in 1% of patients; anomalies can include hypoplasia and supernumerary nipples.

Skeletal and structural anomalies can occur in approximately 14% of patients, including:

- Somatic asymmetry,

- Hemivertebrae,

- Scoliosis,

- Spina bifida,

- Syndactyly,

- Acheiria (congenital absence of the hands - note: other limbs may be affected),

- Ear anomalies,

- Extra ribs,

- Skull deformities,

- Primary pulmonary hypertension,

- Cardiopulmonary failure

The histology of EST is variable, but usually includes malignant endodermal cells. These cells secrete alpha-fetoprotein (AFP), which can be detected in tumor tissue, serum, cerebrospinal fluid, urine and, in the rare case of fetal EST, in amniotic fluid. When there is incongruence between biopsy and AFP test results for EST, the result indicating presence of EST dictates treatment. This is because EST often occurs as small "malignant foci" within a larger tumor, usually teratoma, and biopsy is a sampling method; biopsy of the tumor may reveal only teratoma, whereas elevated AFP reveals that EST is also present. GATA-4, a transcription factor, also may be useful in the diagnosis of EST.

Diagnosis of EST in pregnant women and in infants is complicated by the extremely high levels of AFP in those two groups. Tumor surveillance by monitoring AFP requires accurate correction for gestational age in pregnant women, and age in infants. In pregnant women, this can be achieved simply by testing maternal serum AFP rather than tumor marker AFP. In infants, the tumor marker test is used, but must be interpreted using a reference table or graph of normal AFP in infants.

There are four main signs of acalvaria: absence of the flat bones of the cranial vault, absence of the dura mater and muscles associated with it, skull abnormalities, and the absence of a skull cap. This condition can be diagnosed prior to birth using ultrasonography. Physicians often use magnetic resonance imaging to confirm the diagnosis because in utero, acalvaria is sometimes confused with anencephaly or encephalocele. A distinguishable difference is that with anencephaly, the cerebral hemispheres are missing, but with acalvaria, all parts of the cerebrum are usually present and developed, whereas parts of the calvarium are missing.

Ependymoma is a tumor that arises from the ependyma, a tissue of the central nervous system. Usually, in pediatric cases the location is intracranial, while in adults it is spinal. The common location of intracranial ependymoma is the fourth ventricle. Rarely, ependymoma can occur in the pelvic cavity.

Syringomyelia can be caused by an ependymoma.

Ependymomas are also seen with neurofibromatosis type II.

Ganglioneuroma is a rare and benign tumor of the autonomic nerve fibers arising from neural crest sympathogonia, which are completely undifferentiated cells of the sympathetic nervous system. However, ganglioneuromas themselves are fully differentiated neuronal tumors that do "not" contain immature elements.

Ganglioneuromas most frequently occur in the abdomen, however these tumors can grow anywhere sympathetic nervous tissue is found. Other common locations include the adrenal gland, paraspinal retroperitoneum, posterior mediastinum, head, and neck.

In a case series of 34 patients, Davis and colleagues reported the following signs and symptoms:

- macroscopically visible (gross) hematuria (60%)

- abdominal or back/flank pain (50%)

- significant weight loss (25%)

Other researchers have reported a palpable renal mass or enlarged lymph nodes.

Acalvaria is a rare malformation consisting of absence of the calvarial bones, dura mater and associated muscles in the presence of a normal skull base and normal facial bones. The central nervous system is usually unaffected. The presumed pathogenesis of acalvaria is faulty migration of the membranous neurocranium with normal placement of the embryonic ectoderm, resulting in absence of the calvaria but an intact layer of skin over the brain parenchyma. In other words, instead of having a skull cap protecting the brain, there is only skin covering it. The size of the area that is missing the skull cap can vary from case to case. In extreme cases, the entire top part of the cranium that is dome-shaped may be absent.

The Currarino syndrome (also Currarino triad) is an inherited congenital disorder where either the sacrum (the fused vertebrae forming the back of the pelvis) is not formed properly, or there is a mass in the presacral space in front of the sacrum, and (3) there are malformations of the anus or rectum. It can also cause an anterior meningocele or a presacral teratoma.

Presacral teratoma usually is considered to be a variant of sacrococcygeal teratoma. However, the presacral teratoma that is characteristic of the Currarino syndrome may be a distinct kind.

Hemangioblastomas can cause polycythemia due to ectopic production of erythropoietin as a paraneoplastic syndrome.

Endodermal sinus tumor (EST), also known as yolk sac tumor (YST), is a member of the germ cell tumor group of cancers. It is the most common testicular tumor in children under 3, and is also known as infantile embryonal carcinoma. This age group has a very good prognosis. In contrast to the pure form typical of infants, adult endodermal sinus tumors are often found in combination with other kinds of germ cell tumor, particularly teratoma and embryonal carcinoma. While pure teratoma is usually benign, endodermal sinus tumor is malignant.

Incontinentia pigmenti (IP) is a rare genetic disorder that affects the skin, hair, teeth, nails, and central nervous system. It is named from its appearance under a microscope. It is also known as Bloch–Siemens syndrome, Bloch–Sulzberger disease, Bloch–Sulzberger syndrome, melanoblastosis cutis, and nevus pigmentosus systematicus.

It is characterized by skin abnormalities that begin in childhood, usually a blistering rash which heals, followed by the development of harder skin growths. The skin may develop grey or brown patches which fade with time. Other symptoms can include hair loss, dental abnormalities, eye abnormalities that can lead to vision loss, and lined or pitted fingernails and toenails. Associated problems can include delayed development, intellectual disability, seizures, and other neurological problems. There is no specific treatment, individual conditions must be managed by specialists.