DISCUSSION
Also called ‘’ chorangioma placentae”, placental chorioangioma is the most frequent non-trophoblastic tumor of the placenta which originates from the placental chorionic mesenchyme [3]. Placental chorioangioma accounts for approximately 1% of pregnancies and is predominant in Caucasian women [4]. The majority of researchers consider chorioangioma to be a malformation rather than a true neoplasm [4]. Some environmental factors, namely hypoxic stimulus, high altitude, and vascular growth factors, are possible associations with this tumor’s occurrence [5]. Large chorioangiomas can induce several complications in pregnancy such as polyhydramnios, premature labor, placenta previa, and premature placental separation, leading to high perinatal morbidity and mortality [6,7]. Other complications of large chorioangiomas include placental functional inadequacy, mechanical obstruction of the blood flow, and increased vascular surface area. This induces increased transudation of fluid, resulting in polyhydramnios [8]. The pathological complications seen in the neonates include thrombocytopenia, anemia, stillbirth, edema, non-immune hydrops fetalis, prematurity, intrauterine growth retardation, or fetal death. Arteriovenous shunts in large chorioangiomas cause impairment of the fetal circulation. [9,10]. In the present case, the pregnancy of this 33-year-old primiparous woman with a large placental chorioangioma had prematurity as the only adverse effect. Prematurity was probably the result of the large volume of the placental chorangioma occupying a significant amount of intrauterine volume and therefore leading to the induction of early uterine contractions that culminated in the premature delivery. On ultrasonography, chorioangiomas are well-circumscribed hypoechoic masses that often protrude into the amniotic cavity from the fetal surface near the cord insertion. Calcification and necrosis are occasionally visible [10].
n sonography, the lesion
is well circumscribed and has echogenicity dif-
ferent from that of the rest of the placental tissue.
Large tumors can be of variable shapes, divided
by fibrous septa, and often protrude into the
amniotic cavity from the fetal surface near the
cord insertion
n sonography, the lesion
is well circumscribed and has echogenicity dif-
ferent from that of the rest of the placental tissue.
Large tumors can be of variable shapes, divided
by fibrous septa, and often protrude into the
amniotic cavity from the fetal surface near the
cord insertion
n sonography, the lesion
is well circumscribed and has echogenicity dif-
ferent from that of the rest of the placental tissue.
Large tumors can be of variable shapes, divided
by fibrous septa, and often protrude into the
amniotic cavity from the fetal surface near the
cord insertion
n sonography, the lesion
is well circumscribed and has echogenicity dif-
ferent from that of the rest of the placental tissue.
Large tumors can be of variable shapes, divided
by fibrous septa, and often protrude into the
amniotic cavity from the fetal surface near the
cord insertion In the present case, we used Doppler ultrasound to monitor fetal wellbeing and circulation; however, despite the presence of the large chorioangioma, there were no signs of anemia or cardiac failure. Macroscopically, chorioangiomas are well-circumscribed tumors. On cut section, they are usually fleshy, congested, and red to tan. We occasionally note the presence of myxoid, fibroma-like or degenerative changes. Placental chorioangiomas are often found on the fetal surface of the placenta with a few cases reported on the maternal surface as well [6].
The majority of placental chorioangiomas are small measuring less than 5 cm in diameter and are located entirely in the placental parenchyma; that is why we can be easily miss them if the placenta is not systematically sliced after delivery [11]. In the present case, the tumor measured 8.3 x 4.9 cm and was located on the fetal surface near the umbilical cord insertion with focal cystic change. The definitive diagnosis of placental chorioangioma relies on histopathological examination. Histologically, chorioangioma is a benign tumor proliferation of vessels accompanying connective tissue and an abundant stromal component. The proportion of vascular and stromal components are variable, depending upon the dominant histologic type. The vascular component may comprise either capillaries or sinusoids. Based on histology, the tumor can be classified as capillary, cavernous, endotheliomatous, fibrosing, and fibromatous. Such differentiation is not of clinical concern, since the prognosis depends mainly upon the size of the tumor. In the current case, the tumor was of the capillary type [10-11]. There is a rare variant of chorioangioma: “atypical cellular chorioangioma” characterized by high mitotic activity, cellularity and abnormal nuclei with proliferating malignant trophoblast interspersed among proliferating capillaries with large areas of necrosis [12]. The immunohistochemical study shows a positive immunostaining of tumor cells for CD31, CD 34, factor VIII, GLUT 1, and cytokeratin 18. The differential diagnosis of placental chorioangioma includes chorangiosis and chorangiomatosis. Prognostic factors that influence the outcome of placental chorioangioma are vascularity and location of the tumor. Increased vascularity leads to greater shunting of blood to the physiologic dead space of the tumor, weaning the fetus of a significant amount of nutrient and air exchange and perhaps manifesting as intrauterine growth restriction and fetal demise. Likewise, location is also critical in deciding the pregnancy outcome, as, in certain reported cases, chorioangiomas as small as 2 cm located at the outer edge of the placenta have been associated with complications [8].
Management of chorioangioma depends on its degree of severity. For mild to moderate types, the treatment is conservative as it was the case for our patient. For severe cases, there are several management modalities including in-utero endoscopic devascularization and prenatal treatment by ultrasound guided interstitial laser therapy. In case of fetal anemia, in-utero blood transfusion can be done with good outcome. In case of polyhydramnios, maternal indomethacin therapy or amniocentesis is useful in management. If complications appear late in pregnancy delivery is the option of management. [13].
In summary, placental chorioangioma is associated with an increased risk of complications influencing the outcome of pregnancy. Despite the existence of uncomplicated cases, close monitoring and follow up of the patients by serial ultrasound, surveillance by Doppler, and fetal echocardiography is highly recommended for these patients. Careful examination of the placenta, timely antenatal diagnosis, and early intervention are of paramount importance, to prevent associated morbidity and mortality to both the fetus and the mother. In the current case, except for prematurity, there were no clinically significant complications due to the giant placental chorioangioma measuring 8 cm in diameter.