Germinogenny tumors

Description:

Germinogenny tumors develop from population of pluripotential formative cells. The first formative cells can be found in a vitellicle entoderm already in a 4 weeks embryo. During development of an embryo initial formative cells migrate from a vitellicle entoderm to a genital crest in a retroperitoneuma. Here from formative cells gonads which then go down in a scrotum develop, creating testicles, or in a small pelvis, forming ovaries. If during this migration for some unspecified reasons there is a disturbance of normal process of migration, formative cells can be late in any place of the following where in the subsequent the tumor can be created. Formative cells can be most often found in such areas as retroperitoneal space, a mediastinum, pineal area (strobiloid gland) and sacrococcygeal area. Less often formative cells are late in a vagina, a bladder, a liver, a nasopharynx.

Germinogenny tumors - an infrequent type of tumoral defeat at children. They make 3-8% of all malignant tumors of children's and teenage age. As these tumors can be and high-quality, frequency them, perhaps, much higher. These tumors by two-three times meet among girls more often, than at boys. Mortality among girls is three times higher, than among boys. After 14 years the lethality among males becomes higher that is caused by increase in frequency of tumors of a small egg at boys of teenage age.

Symptoms of Germinogenny tumors:

The clinical picture of germinogenny tumors is extremely diverse and, first of all, is defined by defeat localization. The most frequent localizations are the brain (15%), ovaries (26%), a tailbone (27%), testicles (18%). Much less often these tumors are diagnosed in retroperitoneal space, a mediastinum, in a vagina, a bladder, a stomach, a liver, on a neck (in a nasopharynx).

Small egg.
Primary testicular tumors are rare at children's age. Most often they meet aged up to two years and 25 their % are diagnosed already at the birth. On histologic structure it most often or high-quality teratomas or tumors of a vitellicle. The second peak of diagnosis of tumors of a small egg - the pubertal period when the frequency of malignant teratomas increases. Seminomas at children are extremely rare. The painless, quickly increasing small egg swelling most often is noticed by the child's parents. 10% of testicular tumors are combined with the gidrotsel and other congenital anomalies, especially uric path. At survey the dense, hilly tumor is found, signs of an inflammation are absent. Increase in level of alpha-fetoprotein to operation confirms the diagnosis of the tumor containing vitellicle elements. Pains in lumbar area can be symptoms of metastatic damage of periaortal lymph nodes.

Ovaries.
Ovarian tumors are more often shown by abdominal pains. At survey it is possible to find the tumoral masses located in a small basin, and also in an abdominal cavity, increase in volume of a stomach at the expense of ascites is frequent. Such girls quite often have a fever.

Dizgerminoma - the most frequent ovarian germinogenny tumor which is preferential diagnosed in the second decade of life and it is rare - at little girls. The disease quickly enough extends to the second ovary and a peritoneum. Vitellicle tumors also meet more often at girls of the pubertal period. Tumors are usually unilateral, the big sizes therefore, a rupture of the capsule of a tumor - the frequent phenomenon. Clinical manifestations of malignant teratomas (teratocarcinomas, embryonal carcinomas) usually have a nonspecific picture with existence of tumoral masses in a small basin, disturbance of a menstrual cycle can be observed. At patients in the prepubertatny period the condition of a psevdopubertatnost (early puberty) can develop. High-quality teratomas - usually cystous, can come to light at any age, quite often give clinic of torsion of an ovary with the subsequent rupture of an oothecoma and development of diffusion granulematozny peritonitis.

Vagina.
It is practically always the vitellicle tumors all the described cases took place aged up to two years. These tumors are usually shown by vaginal bleedings or bloody allocations. The tumor proceeds from lateral or back walls of a vagina and has an appearance of polipovidny masses, is frequent on a leg.

Sacrococcygeal area.
It is localization of germinogenny tumors, the third on frequency. Frequency of these tumors makes 1:40000 newborn children. In 75% of cases the tumor is diagnosed up to two months and it is almost always a mature high-quality teratoma. Clinically at such patients tumoral educations in a crotch or a buttock come to light. Most often it is very big tumors. In certain cases new growths have intra belly distribution and are diagnosed at more advanced age. In these cases the histologic picture most often has more malignant character, is frequent with vitellicle tumor elements. The progressing malignant tumors of sacrococcygeal area quite often lead to the dysuric phenomena, problems with the act of defecation and an urination, neurologic symptoms appear.

Mediastinum.
Germinogenny tumors of a mediastinum in most cases represent a tumor of the large sizes, however the syndrome of a prelum of an upper vena cava arises seldom. The histologic picture of a tumor of preferential mixed genesis also has the teratoid component and tumor cells characteristic of a vitellicle tumor. Brain.
Germinogenny tumors of a brain make about 2-4% of intracranial new growths. In 75% of cases are observed at boys, except for area of the Turkish saddle where tumors are izlyublenno localized at girls. Germinomas form big infiltriruyushchy tumors which quite often are a source of ventrikulyarny and subarachnoidal cerebrospinal metastasises. Not diabetes mellitus can advance other symptoms of a tumor.

Reasons of Germinogenny tumors:

Malignant germinogenny tumors are very often connected with various genetic anomalies, such as an ataxy telangiectasia, Klinefelter syndrome, etc. These tumors are often combined with other malignant tumors, such as a neuroblastoma and hemoblastoses. The neostarted-up testicles represent risk for development of tumors of a small egg.

Patients with germinogenny tumors most often have a normal karyotype, however breakdown in the I chromosome quite often comes to light. The genome of a short shoulder of the first chromosome can double or be lost. Multiple examples of germinogenny tumors at sibling, twins, mothers and daughters are noted.

The differentiation on the embryonal line gives development of teratomas of various degree of a maturity. The malignant ekstraembrionalny differentiation leads to development of choriocarcinomas and tumors of a vitellicle.

Quite often germinogenny tumors may contain cells of various lines of a differentiation of formative cells. So, teratomas can have population of cells of a vitellicle or trophoblasts.

Frequency of each histologic type of a tumor varies depending on age. High-quality or unripe teratomas meet at the birth, a vitellicle tumor aged from a year up to five years more often, dizgerminoma and malignant teratomas are most frequent at teenage age, seminomas meet more often after 16 years.

The factors causing malignant changes are unknown. Chronic diseases, prolonged drug treatment during pregnancy of mother can be connected with increase in frequency of germinogenny tumors at children.

The morphological picture of germinogenny tumors is very different. Germinomas consist of groups of big same neoplastic cells with the blown-up kernel and light cytoplasm. Tumors of a vitellicle have very characteristic picture: a mesh stroma, quite often it call lacy in which sockets of the cells containing a-fetoprotein in cytoplasm are located. Trophoblastic tumors produce a chorionic gonadotrophin. The high-quality high-differentiated teratomas often have a cystous structure and contain various fabric components, such as a bone, a cartilage, hair, ferruterous structures.

The pathomorphologic conclusion for germinogenny tumors has to include:
- localization of a tumor (organ accessory);
- histologic structure;
- condition of the capsule of a tumor (its integrity);
- characteristics of a lymphatic and vascular invasion;
- spread of a tumor on surrounding fabrics;
- an immunohistochemical research on AFP and HCG.

There is a correlation between a histologic structure and localization of primary tumor: vitellicle tumors preferential affect sacrococcygeal area and gonads, and at children up to two years more often tumors of a tailbone and testicles whereas tumors of ovaries and pineal area are more often diagnosed for seniors (6-14 years) are registered.

Choriocarcinomas - rare, but extremely malignant tumors most of which often arise in a mediastinum and gonads. They can also be inborn.

For dizgerminy typical localization is the pineal area and ovaries. Dizgerminoma make about 20% of all tumors of ovaries at girls and 60% of all intracranial germinogenny tumors.

The embryonal carcinoma in "a pure look" seldom meets at children's age, the combination of elements of embryonal cancer to other types of germinogenny tumors, such as teratoma and tumor of a vitellicle most often is registered.

Treatment of Germinogenny tumors:

In case of suspicion on existence of a tumor of the germinogenny nature in an abdominal cavity or in a small basin operation can be made for the purpose of an oncotomy or (in case of a tumor of the big sizes) for receiving morphological confirmation of the diagnosis. However quite often surgical intervention is applied according to urgent indications, for example, at torsion of a leg of a cyst or a rupture of the capsule of a tumor.

At suspicion of a tumor of an ovary it is not necessary to be limited to a classical cross gynecologic section. The median laparotomy is recommended. When opening an abdominal cavity lymph nodes of a small pelvis and retroperitoneal area are investigated, the surface of a liver, subphrenic space, a big epiploon and a stomach look round.

In the presence of ascites - the cytologic research of ascitic liquid is necessary. In the absence of ascites it is necessary to wash out an abdominal cavity and area of a small pelvis and to subject to a cytologic research the received washing waters.

At detection of a tumor of an ovary the tumor has to be subjected to an urgent histologic research, removal of an ovary only after confirmation of the malignant nature of a tumor. Such practice allows to avoid removal of not struck bodies. If massive tumoral defeat takes place, it is necessary to avoid not radical operations. In such cases the preoperative course of chemotherapy, then "second look" operation is recommended. If the tumor is localized in one ovary, removal of one ovary can be sufficient. At damage of the second ovary whenever possible it is necessary to keep a part of an ovary.

Recommendations when using an operational method at damage of ovaries:
1. It is not necessary to use a cross gynecologic section.
2. Median laparotomy.
3. In the presence of ascites - the cytologic research is obligatory.
4. In the absence of ascites - to wash out an abdominal cavity and area of a small pelvis; cytologic research of washing waters.
5. Survey and if necessary biopsy:
- lymph nodes of a small pelvis and retroperitoneal area;
- surfaces of a liver, subphrenic space, big epiploon, stomach.

The sacrococcygeal teratomas diagnosed most often at once after the child's birth have to be removed immediately to avoid a tumor malignancy. Operation has to include full removal of a tailbone. It reduces probability of a recurrence of a disease. Malignant sacrococcygeal tumors have to be treated by chemotherapy in the beginning, then operation with the purpose of removal of a residual tumor follows.

Operative measure for the purpose of a biopsy at a local tumor in a mediastinum and a persistention of AFP is not always justified as it is connected with risk. Therefore carrying out preoperative HT and after reduction of the sizes of a tumor - operational removal it is recommended.

At defeat of a small egg the orkhiektomiya and high bandaging of a seed cord is shown. The retroperitoneal limfadenektomiya is carried out only according to indications.

Radiation therapy.
Lechevy therapy has very limited use in treatment of germinogenny tumors. It can be effective at treatment dizgerminy an ovary.

Chemotherapy.
The leading role in treatment of germinogenny tumors belongs to chemotherapy. Many chemotherapeutic drugs are effective at this pathology. Long time the polychemotherapy was widely used by three cytostatics: Vincristinum, Actinomycinum "Д" and Cyclophosphanum. However recently it is preferred as other drugs, on the one hand, new and more effective, on the other hand, - having the smallest number remote последствийю, and, first of all, reducing risk of sterilization. Most often now at germinogenny tumors platinum drugs (in particular, карбоплатин), вепезид and Bleomycinum are used.