What is a Teratoma?

Teratomas are a common type of ovarian germ cell tumors. They are derived from germ cells and are divided into mature teratomas (that is, benign teratomas) and immature teratomas (malignant teratomas). Benign teratomas contain many components, including skin, hair, teeth, bones, oils, and nerve tissues; malignant teratomas are poorly differentiated, have no or little formed tissue, and have an unclear structure. Most early teratoma has no obvious clinical symptoms, and most of them were found by accident during physical examination.

Basic Information

English name

teratoma

Visiting department

Obstetrics and Gynecology

Common causes

Possibly due to abnormal differentiation of embryonic germ cells

Common symptoms

Common abdominal mass with nausea, vomiting, bleeding, etc.

Causes of teratoma

The etiology is unclear, which may be related to the abnormal differentiation of embryonic germ cells.

Clinical manifestations of teratoma

Intracranial teratoma

Because intracranial teratoma is usually located at the midline, there are often no obvious signs of brain localization. Most patients have elevated intracranial pressure as the first symptom, manifesting as headache, nausea, and vomiting. Bilateral papillary oedema can be seen on ophthalmic examination. Teratoma located in the pineal gland area can appear binocular upper vision, ataxia, precocious puberty, and cranial nerve palsy. People with saddle regions may have diabetes insipidus, drowsiness, visual field disturbance, and water and fat metabolism disorders. In the posterior cranial fossa, cerebellar damage and neck stiffness may occur. The cerebellopontine angle may cause headache, vomiting, diplopia, ataxia, deafness, nystagmus, and cranial nerve injury.

2. Gastric teratoma

The clinical manifestations are abdominal masses, mostly in the left upper abdomen, bloating, vomiting, vomiting blood and / or melena, dyspnea, and anemia. In neonates or infants, upper abdominal mass and upper gastrointestinal bleeding (most common in intermittent black stools) are the main clinical manifestations.

3. Testicular teratoma

The age of high incidence of testicular teratoma can be divided into children and adults. The age of high incidence of child testicular teratoma is 1 to 2 years, and the age of high incidence of testicular teratoma is 25 to 35 years. The vast majority of patients present with painless testicular masses that are hard, nodular, or irregular.

4. Ovarian teratoma

The incidence of this disease is high. The metastasis spreads along the peritoneum. Common metastases include pelvic and peritoneal peritoneum, omentum, liver surface, diaphragm, intestine and mesentery. Most of the metastases are surface implants. Lymph node metastasis is not uncommon.

5. Tail tail teratoma, etc.

Tail teratoma varies in size, and patients often have difficulty urinating and defecation. Swelling of the buttocks is sometimes seen, and there may be a mass at the tail. Because tumors tend to grow to one side and grow to the buttocks, the buttocks often appear asymmetric. Sometimes the tumor bulges from the perineum. Rectal compression or involvement may cause constipation or incontinence. People with huge tumors can affect the delivery of their mother. Pre-condylar mass can be touched during digital rectal examination. Malignant teratoma grows rapidly with progressive constipation and difficulty urinating.

Teratoma test

Intracranial teratoma

Intracranial teratoma mainly occurs in midline regions such as the upper saddle region and the pineal gland region, and its imaging characteristics have significant characteristics, which can make a preliminary diagnosis.

(1) Lumbar puncture The pressure of lumbar puncture in most patients is increased to varying degrees, and the cerebrospinal fluid protein content is generally not high.

(2) X-ray films of the craniocerebral brain Most of them show signs of increased intracranial pressure. If teeth, small bone masses, and calcified images are found, it is more helpful for qualitative diagnosis.

(3) CT scan CT scan shows irregular masses, nodular and lobular and densely space-occupying lesions, usually with solid components (high density), cystic lines (low density), and Calcification and ossification are common in polycystic cases. Fat components were seen in all patients, and intratumoral bleeding was rare. There are a few cases where the fatty fluid in the ventricle can swim with changes in body position (caused by the rupture of the teratoma into the ventricle). It is difficult to distinguish between teratoma and malignant teratoma on plain CT, but the latter capsule becomes There are relatively few cents, calcifications and fats, and there are more substantial parts. Benign teratomas have often grown for many years, and the tumors are usually large when they are found. Almost all patients in the pineal region have dilated supraventricular ventricles. After injection, the solid part is obviously strengthened, the density is extremely uneven, and the cyst wall enhancement can present multiple ring shadows.

(4) The signals appearing on T ₁ and T ₂ images on MRI are extremely mixed, but the boundaries are clear, nodular or lobulated, and the benign teratoma boundary is edema-free (T2 image shows clear high signals). Peripheral edema, suggesting that the tumor is a malignant or teratoma, and the tumor wall and parenchyma were significantly strengthened after the injection.

(5) The tumor marker CEA may increase slightly or moderately. Patients with immature teratoma and mixed GCT containing this component have significantly increased AFP.

2. Gastric teratoma

(1) X-ray examination Plain film of the abdomen In the middle and upper abdomen or the whole abdomen, uneven density shadows can be seen. The border can be unclear and squeeze the bowel to the lower right front. Strip-like bone-like or stippled sand-like calcification can be seen in the shadow of the mass. Barium meal fluoroscopy shows that the stomach is compressed and deformed, and the small intestine is shifted downward. Filling defects can be seen in the stomach, which can also expand, and gas-liquid levels and a large amount of fluid can appear. Between the leaflets. Barium enema shows the transverse colon, descending colon and sigmoid colon, and the upper abdomen shows a huge dense shadow. Pelvic venography shows that the left renal pelvis is displaced downwards, and the upper edge of the bladder may be indented.

(2) B-ultrasound Presentation of a variety of sonograms. A scan of the left upper abdomen shows that the mass is located between the spleen and kidney, and the boundary can be clearly displayed or unclear. The mass can be multilocular lobulated, and its internal acoustic phase can be solid, multiple cystic, or mixed, and may also show calcifications.

(3) CT examination If the lesion is huge, even occupying 4/5 of the abdominal cavity, multiple organs are displaced by compression. The internal structure of the lesion is disordered and uneven in density, showing mixed dense shadows, and can also be composed of solid and cystic components.

(4) Gastroscopy is rarely used, only the size of the lesions in the gastric cavity and the surface conditions, such as bleeding, erosion and superficial ulcers, can be observed. Biopsy under direct vision is an advantage, but for gastric teratomas Little help.

3. Testicular teratoma

B-ultrasound has important clinical value for judging the nature, size, location of testicular tumors, the proportion of tumors in testicular tissue, and even the choice of treatment. B-ultrasound of testicular teratoma shows clear mass boundaries, cystic solidity, cartilage in the mass, immature bone tissue or calcification. Serum alpha fetoprotein (AFP) levels in adult patients with testicular teratoma are related to benign and malignant. AFP levels in children with testicular teratoma are within the normal range of the corresponding age group, but the blood AFP levels of normal infants within 6 months are significantly different. Therefore, there is no clear clinical hint for the level of AFP levels in infant patients within 6 months. significance.

4. Ovarian teratoma

(1) AFP in serum of patients with serum alpha-fetoprotein (AFP) is lower than that of ovarian yolk sac tumor, which may be because the endoderm tissue of immature teratomas can also secrete a small amount of AFP, and there may be a lot of germ cell malignant tumors. Is a mixed type. Immature teratoma may contain a small amount of yolk sac tumor components, which can synthesize a small amount of AFP.

(2) Nerve cell-specific enolase (NSE) immature ovarian teratoma contains mature or immature nerve cells. Sometimes NSE can be detected in the serum, which is of reference significance for the diagnosis of this disease.

(3) Other B-mode, CT, MRI, laparoscopic, and histopathological examinations.

5. Tail Tail Teratosis

(1) Laboratory tests The blood AFP (alpha-fetoprotein) test has a high positive rate. When there is a bacterial infection, the white blood cell count and neutrophil count of peripheral blood are significantly increased.

(2) X-ray film of other auxiliary examination showed bone and tooth shadow in the tumor. Lateral image shows a tumor in the tail of the palate. The barium enema shows the rectum bent forward. Intravenous pyelography helps to determine the extent and location of tumors and whether metastases are required. X-ray examination of the chest and bones is required.

Teratoma diagnosis

The positive rate of alpha-fetoprotein in malignant teratoma is as high as 80%, and the malignant part is mainly yolk sac carcinoma. About 50% of benign teratomas are positive for alpha-fetoprotein. AFP test is very helpful for diagnosis.

Teratoma differential diagnosis

The disease should be distinguished from craniopharyngioma, pituitary adenoma, dermoid cysts and epithelioid cysts, hypothalamus and cruciate glioma, yolk sac tumor, choriocarcinoma, and myelomeningocele.

Teratoma treatment

Intracranial teratoma

Benign teratoma needs surgical resection, but the three-dimensional multi-point sampling of pathological specimens must be emphasized to avoid missed diagnosis of malignant components. If fully cut, it is hoped that the cure. Because the tumor is often located at the midline site, it is difficult to perform a complete resection. Those who cannot completely resection may perform cerebrospinal fluid shunting as appropriate to relieve obstructive hydrocephalus. Radiotherapy and chemotherapy are not effective for benign teratoma. Immature and malignant teratoma are treated with chemotherapy and then radiotherapy. If the tumor does not disappear, surgical resection will be performed, and chemotherapy will continue for 2 courses.

2. Gastric teratoma

Gastric teratomas are mostly benign, with early surgical resection and good prognosis. Long-term follow-up should be performed after surgery, and AFP should be reviewed regularly. If there is no decline or rise after fall, it indicates recurrence or metastasis, and further treatment is needed.

3. Testicular teratoma

Surgery is the preferred treatment for testicular teratoma. For children with testicular teratoma, those with normal AFP levels, B-mode ultrasonography suggesting normal testicular parenchyma, and frozen pathological findings during the operation to exclude malignant tumors may consider performing testicular preservation.

Testicular dermoid cysts and children with testicular teratoma require no additional treatment after surgery. Patients with post-pubertal testicular teratoma with retroperitoneal lymph node metastasis undergo radical orchiectomy + retroperitoneal lymph node dissection. Most teratoma metastases are consistent with the pathological type of the primary tumor, but embryonic cancer components are also found in teratomas. Malignant transformation in distant metastatic teratomas does not respond well to chemotherapy for germ cell tumors.

4. Ovarian teratoma

(1) Principles of treatment The principle of treatment of immature ovarian teratoma: the principle of surgery, which adopts a surgical method to preserve fertility; after surgery, effective combined chemotherapy should be taken early. For recurrent tumors, the malignant degree of immature teratoma should be determined Reverse the law, and make different specific plans in combination with different specific situations.

(2) Surgical treatment The scope of surgery The vast majority of tumors are unilateral. Patients are often young, and they often advocate unilateral appendectomy to preserve fertility. If the patient has no fertility requirements and the tumor is stage II or III, bilateral appendages and hysterectomy can be performed. Omentum is a common site of metastasis. Regardless of the stage of the tumor, the omentum is resected. There is no consensus on whether the retroperitoneal lymph nodes are routinely removed. Those with extensive abdominal cavity metastasis should perform tumor cytoreductive surgery as much as possible to achieve basic tumor clearance. Surgical treatment of recurrent tumors The recurrence of immature teratomas is still mainly surgical resection, supplemented by effective combined chemotherapy. Second exploration surgery is not currently recommended.

(3) Chemotherapy Chemotherapy is an indispensable treatment method for immature ovarian teratoma. After the first surgery, early combined chemotherapy is used to prevent recurrence and improve survival.

5. Tail Tail Teratoma

Surgery is the preferred therapy. The tailbone must be removed together. There are often tumor cells on the coccyx, and if the resection is incomplete, it will recur even if the teratoma is benign. Newborns should undergo surgery as soon as possible after birth to avoid malignant changes. Special attention should be paid to the treatment of the anterior iliac artery during surgery to prevent danger from bleeding. Pay attention to lymph node metastasis during surgery. In addition to surgical removal of the malignant tail teratoma, radiation therapy and chemotherapy must be given.