Chorioangioma is a vascular placental tumor originating from the tissues of the embryo. It usually proceeds asymptomatically. It can manifest itself with polyhydramnios, signs of fetal hypoxia. It is diagnosed by ultrasound, dopplerography of the uterine blood flow. It is recommended to monitor the fetal condition using fetometry, CTG, phonocardiography, echocardiography. Indolylacetic acid derivatives, tocolytics, angioprotectors, membrane stabilizers, antihypoxic agents, discharge amniocentesis, intrauterine intrauterine hemotransfusion, methods of tumor devascularization are used for treatment. In the presence of large chorioangioma, a caesarean section is indicated.
O43.8 Other placental disorders
Chorioangioma (hemangioma, hamartoma) of the placenta is the most common benign neoplasia of placental tissue, which occurs with a frequency of 0.2-139 cases per 10,000 births. However, with a more thorough morphological examination of the afterbirth, characteristic pathohistological changes are found in at least 1% of the materials.
Chorioangioma are nontrophoblastic tumors that consist of many capillaries formed at 2-3 weeks of gestational age from primitive chorial mesenchyma. Placental hemangiomas are usually detected at 19-36 weeks of pregnancy. The relevance of timely diagnosis of the disease is due to the high risk of fetal hypotrophy and its antenatal death in hypervascularized tumors larger than 50 mm.
The etiology of the formation of placental tissue by hamart has not been definitively established to date, which is due to a small number of clinical cases of the disease. Based on a thorough analysis of statistical data, specialists in the field of obstetrics and gynecology have identified three possible causes with which chorioangiomatosis is more often associated:
- Chromosomal abnormalities. Confirmation of the role of genetic factors and congenital malformations is an increase in the frequency of pathology by 4-6 times in the presence of a single umbilical artery, fetal skin hemangiomas. Chorioangioma are often combined with Edwards disease, congenital heart defects, vascular anomalies, hydrocephalus.
- Pregnancy complications. The probable cause of the formation of a placental hamartoma may be the isoserological incompatibility of the blood of the mother and child. This theory is supported by the more frequent detection of vascular overgrowth in Rh incompatibility. Risk factors also include multiple pregnancies, intrauterine infection of the fetus.
- Extragenital pathology. Patients with diagnosed chorioangioma are more likely than other pregnant women to suffer from diabetes mellitus. The tumor process is probably caused by microcirculatory disorders characteristic of endocrinopathy. Vascular damage by nicotine can provoke the formation of placental hemangiomas in women with nicotine addiction.
Chorioangioma is formed by the capillaries of the fetus, which have grown inside the chorionic villi. The trigger factor of enhanced angiogenesis is still unknown. The pathogenesis of disorders detected in large vascular tumors is due to the peculiarities of the distribution of blood flow in the branched capillary bed of the hemangioma. The deposition of blood by chorioangioma leads to insufficient receipt of nutrients and oxygen by the fetus. A “vortex” blood flow in convoluted blood vessels can provoke the occurrence of a deficiency of a number of clotting factors and disorders in the hemostasis system. The formation of arteriovenous shunts in large placental hemangiomas is accompanied by an increase in venous return to the child’s heart and an increase in cardiac output. In some cases, hemodynamic disorders potentiate fetal anemia. The course of the tumor process is benign. Placental hamartomas do not metastasize to other organs.
The systematization of variants of placental chorioangioma is based on taking into account the features of their histological structure, the ratio of stroma and vascular elements. Although the composition of the tumor is often mixed, based on the leading component, it is justified to distinguish three histological types of placental hemangiomas, which differ in the likelihood of developing complications dangerous to the child and the degree of severity of symptoms:
- Low-differentiated solid formations. The structure of neoplasia is dominated by cellular elements with a low degree of differentiation. The degree of development of the vascular component may be different. Clinical symptoms are usually absent.
- Angioblastic chorioangioma. Tumors with a predominance of angiomatosis are the most common and dangerous. They are characterized by an extensive vascular network and arteriovenous shunts. Fetal losses in such hemangiomas reach 30%.
- Degenerative tumors. The neoplasm is usually solid and has a low degree of vascularization. Due to degenerative changes inside the chorioangioma and along its periphery, vascular-free cavities are formed. It is asymptomatic.
Symptoms of placental chorioangioma
With small neoplasms, disturbances in the fetoplacental complex are minimal or absent. A pregnant woman usually does not make any complaints about the subjective deterioration of the condition. The severity of clinical symptoms in placental chorioangioma is directly related to the size of vascular neoplasia. According to research, in 14-33% of cases of the disease, polyhydramnios is noted, which is externally manifested by an increase in the volume of the abdomen longer than the gestational period. If complications occur on the part of the fetus, a woman may first notice an increase in its movements, and then a decrease until fading.
Complicated course of chorioangiomatosis is usually noted in angioblastic vascular formations larger than 50.0 mm. Arteriovenous bypass surgery leads to the development of fetal anemia, thrombocytopenia, hypoproteinemia, cardiomegaly, heart and liver failure. With severe metabolic disorders, fetal development may be delayed, and in severe cases, its antenatal death. Pregnant women with placental chorioangioma have an increased risk of miscarriage, hypotonic and coagulopathic bleeding after childbirth. Premature placental abruption and preeclampsia are four times more common than in the general population.
In most cases, low-grade and degenerative placental hemangiomas of small size become a godsend during routine ultrasound screening of pregnancy. Diagnostic search for suspected Chorioangioma is aimed at detecting a tumor and assessing the condition of the child. The most informative for diagnosis are:
- Ultrasound of the placenta. Single cystic or solid formations with clear boundaries (a well-defined capsule or pseudocapsule) are detected on the fruit surface of placental tissue near the place of umbilical cord departure. Sometimes chorioangioma are multiple, placed on the fetal membranes, vascular pedicle, in the thickness of the placenta.
- Dopplerography of uteroplacental blood flow. The study is prescribed to determine the degree of vascularization and modeling the structure of the chorioangioma vascular bed. With its help, it is possible to detect the connection of the blood supply of the tumor with the vessels of the umbilical cord. For greater informativeness, the method is supplemented with color Doppler mapping.
- Additional diagnostic methods. Cardiotocography, fetometry, and phonocardiography of the fetus are recommended as methods that allow an objective assessment of the child’s condition. During fetal echocardiography, possible cardiomegaly can be detected. In the postpartum period, the diagnosis of chorioangioma is confirmed histologically.
To distinguish between chorioangioma and other pathologies, consultations of an oncologist, mammologist, hematologist are prescribed. The disease is differentiated with:
- placental teratomas;
- metastases to placental tissue of malignant tumors of the mother (melanoma, lymphoma, sarcoma, breast cancer, ovarian neoplasms) and the child (neuroblastoma, giant pigmented nevus);
- partial bubble drift;
- submucous uterine fibroids;
- retroplacental hematomas.
Treatment of placental chorioangioma
The choice of pregnancy management tactics and delivery method when hamartoma is detected in the placenta depends on the size of the neoplasm, its localization, the severity of pathological symptoms, and the presence of complications. If a small placental hemangioma is detected, which does not manifest clinically in any way, ultrasound monitoring in dynamics is recommended to monitor the growth rate of the tumor.
Patients with angioblastic chorioangioma and the presence of clinical signs of the disease are shown medication and invasive therapy, the main objectives of which are:
- Reduction of polyhydramnios. According to the observations of obstetricians and gynecologists, the appointment of indomethacin has a positive effect with a significant increase in the volume of amniotic fluid, which can provoke premature birth. In some cases, serial unloading amniocentesis is used to prolong pregnancy to a safe period for the child.
- Treatment of the consequences of fetoplacental insufficiency. In the absence of indications for urgent delivery, angioprotectors and tocolytics that improve uteroplacental blood flow are used to improve the nutrition of the child. The resistance of fetal tissues to hypoxia is increased by antihypoxic drugs and membrane stabilizers.
- Correction of severe fetal anemia. To improve the hematological parameters of the child with their significant decrease, modern methods of intrauterine blood transfusion are used. At the same time, a puncture of the anterior wall of the pregnant woman’s abdomen and uterus is performed, washed donor red blood cells are injected into the dotted umbilical vein.
The rapid growth of chorioangioma in the second and early third trimester of pregnancy is stopped by injecting pure ethyl alcohol into the tumor tissue or embolization of its vessels under ultrasound control. Intra-tumor blood flow can be reduced or completely stopped during fetoscopic electro- or laser coagulation of blood vessels.
The issue of delivery with an uncomplicated course of the disease is resolved at 36-37 weeks. Most patients are shown natural childbirth. With the detection of a large placental chorioangioma, the formation of multiple fluid formations on the surface of the placenta, significant vascularization and the presence of an arteriovenous shunt, an early cesarean section is indicated. The increase in signs of fetal hypotrophy, placental abruption, the appearance of other complications threatening the child serves as an indication for emergency delivery.
Prognosis and prevention
With small solid and degenerative placental hemangiomas, the prognosis is favorable. Timely diagnosis, adequate support of pregnancy and childbirth with angioblastic chorioangioma can reduce the risk of perinatal morbidity and mortality. Primary prevention of the disease is not offered. The action plan for secondary prevention includes early registration in a women’s clinic and compliance with the timing of ultrasound monitoring of pregnancy, especially in the presence of predisposing factors (diabetes mellitus, smoking, a history of multiple pregnancies).