Chorangioma and related vascular lesions of the placenta--a review.

Chorangioma has been referred to as a hamartoma-like, or a hyperplastic capillary lesion, rather than a true neoplasm. Its incidence is 1 in 100 placentas. In chorangiomas larger than 4 cm, there can be significant effects on the hemodynamic and circulatory processes of the fetus, leading to grave clinical consequences, such as polyhydramnios and fetal heart failure. Chorangiomas can show various histopathologic pictures, ranging from vascular to cellular, and can undergo degenerative changes. They can be diagnosed prenatally by ultrasound, color Doppler imaging, and magnetic resonance imaging (MRI). Chorangioma must be differentiated from other villous capillary lesions, namely, chorangiomatosis and chorangiosis. They have overlapping similarities with chorangioma, and have clinical implications. Chorangiomatosis has been associated with negative fetal outcomes such as intrauterine growth retardation (IUGR) and preeclampsia. Chorangiosis is associated with maternal diabetes mellitus. Another rarer differential is chorangioma with trophoblast proliferation ("chorangiocarcinoma," a probable misnomer), a rare proliferation of trophoblastic tissue seen in the vicinity of otherwise benign chorangioma. Treatment modalities of chorangioma include endoscopic devascularization, alcoholic ablation, and interstitial laser coagulation. In this article, we will review the clinical and pathologic picture of chorangioma as well as treatment, and discuss its main differentials.