Chorioangioma, or chorangioma, is a

benign tumor A benign tumor is a mass of cells (tumor) that does not invade neighboring tissue or metastasize (spread throughout the body). Compared to malignant (cancerous) tumors, benign tumors generally have a slower growth rate. Benign tumors have re ...

placenta The placenta is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate mater ...

. It is a

hamartoma A hamartoma is a mostly benign, local malformation of cells that resembles a neoplasm of local tissue but is usually due to an overgrowth of multiple aberrant cells, with a basis in a systemic genetic condition, rather than a growth descended fr ...

-like growth in the

consisting of

blood vessel The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...

s, and is seen in approximately 0.5 to 1% pregnancies. It is mostly diagnosed ultrasonically in the

second trimester Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins. Pregnancy usually occurs by sexual intercourse, but ca ...

of pregnancy. Large chorioangiomas are known to cause complications in pregnancy, while the smaller ones are asymptomatic.

Presentation

Most chorangiomas are not clinically significant, i.e. they do not have an adverse effect on placental function.

Complications

Large (greater than 4 or 5 cm.) or multiple chorioangiomas may lead to complication. The complications are polyhydramnios,

preterm labour Preterm birth, also known as premature birth, is the birth of a baby at fewer than 37 weeks gestational age, as opposed to full-term delivery at approximately 40 weeks. Extreme preterm is less than 28 weeks, very early preterm birth is between ...

hemolytic anemia Hemolytic anemia or haemolytic anaemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels (intravascular hemolysis) or elsewhere in the human body (extravascular). This most commonly ...

, fetal

cardiomegaly Cardiomegaly (sometimes megacardia or megalocardia) is a medical condition in which the heart is enlarged. As such, it is more commonly referred to simply as "having an enlarged heart". It is usually the result of underlying conditions that make t ...

, fetal

thrombocytopenia Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients an ...

intrauterine growth retardation Intrauterine growth restriction (IUGR), or fetal growth restriction, refers to poor growth of a fetus while in the womb during pregnancy. IUGR is defined by clinical features of malnutrition and evidence of reduced growth regardless of an infant's ...

preeclampsia Pre-eclampsia is a disorder of pregnancy characterized by the onset of high blood pressure and often a significant amount of protein in the urine. When it arises, the condition begins after 20 weeks of pregnancy. In severe cases of the disease ...

, abruption of placenta and

congenital anomalies A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can r ...

Pathogenesis

The origin of chorioangioma is from primitive chorionic

mesenchyme Mesenchyme () is a type of loosely organized animal embryonic connective tissue of undifferentiated cells that give rise to most tissues, such as skin, blood or bone. The interactions between mesenchyme and epithelium help to form nearly every o ...

. It develops when the

s and stroma undergo rapid proliferation independent of the surrounding tissue. Based on

histological Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...

features, chorioangioma is classified by Marchetti into three types: *Cellular type : This type is immature and contains mostly cellular elements packed compactly. * Angiomatous (vascular) type : This is the most common type of

choriocarcinoma Choriocarcinoma is a malignant, trophoblastic cancer, usually of the placenta. It is characterized by early hematogenous spread to the lungs. It belongs to the malignant end of the spectrum in gestational trophoblastic disease (GTD). It is also c ...

. It is distinguished by the presence of numerous small blood vessels. * Degenerative type : This is the mature type with degenerative changes. Each type is believed to represent a phase of tumor development. Chorioangioma has no

malignant Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

potential.

Diagnosis

Most chorioangiomas are

asymptomatic In medicine, any disease is classified asymptomatic if a patient tests as carrier for a disease or infection but experiences no symptoms. Whenever a medical condition fails to show noticeable symptoms after a diagnosis it might be considered asy ...

. They are generally picked up in second trimester scan. Chorioangioma is seen as a hypo- or hyperechoic circumscribed mass that is distinct from the placenta at gray-scale US examination. Large lesions may contain fibrous septa. It is seen protruding into the amniotic cavity near the insertion of the cord. Doppler examination shows anechoic cystic areas, with pulsatile flow in spectral analysis. Some chorioangiomas may be solid masses, and may not be identifiable in gray-scale imaging. Therefore, the investigation of choice is Colour Doppler, which also distinguishes it from placental hematoma. They can also be detected with

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

. Histologically, chorioangiomas consist of abundant vascular channels and may be cellular.

Management

Expectant management Watchful waiting (also watch and wait or WAW) is an approach to a medical problem in which time is allowed to pass before medical intervention or therapy is used. During this time, repeated testing may be performed. Related terms include ''expec ...

is recommended for chorioangioma as majority of them are asymptomatic. Large tumors are monitored with ultrasonogram every 1–2 weeks. In case of maternal or foetal complications, possible interventions are serial foetal transfusions, fetoscopic

laser coagulation Laser coagulation or laser photocoagulation surgery is used to treat a number of eye diseases and has become widely used in recent decades. During the procedure, a laser is used to finely cauterize ocular blood vessels to attempt to bring about var ...

of vessels supplying the tumor, endoscopic surgical devascularization and chemosclerosis using absolute alcohol.

Prognosis

Large chorioangiomas with decreased echogenicity, decreased tumor volume and decreased blood flow in colour doppler images are may undergo spontaneous infarction. When chorioangiomas have deceased

blood flow Hemodynamics or haemodynamics are the dynamics of blood flow. The circulatory system is controlled by homeostatic mechanisms of autoregulation, just as hydraulic circuits are controlled by control systems. The hemodynamic response continuously m ...

, fetal hemodynamics and clinical outcome are found to be improved.

Epidemiology

It is the most common tumor of the placenta. Chorioangiomas over the size of 5 cm in diameter are rare, and occur at a rate of 1:3500 to 1:16,000 births. Smaller chorioangiomas are more frequent, with an incidence of 14‑139:10,000 births. However, many small chorioangiomas may not be sonologically visible and hence go unreported. In a clinical study, more than half of all tumors were discovered only by histological techniques.

History

Chorioangioma was first described by Clarke in 1798.

References

External links

Chorangioma (pathweb.uchc.edu)Chorangioma (humpath.com)
{{Vascular tumors Gynaecological neoplasia Health issues in pregnancy