Atypical Cellular Chorangioma: A Potential Diagnostic Pitfall With Worrisome Aspects but a Favorable Prognosis

Whole exome sequencing of placental chorangioma

INTRODUCTION

Placental chorangioma is a benign non-trophoblastic vascular proliferation of the placental chorion favored to represent hamartoma-like or hyperplastic capillary lesions. As the exact pathophysiology has not been established, we investigated the molecular characteristics of placental chorangiomas using exploratory whole exome sequencing.

METHODS

Three cases were retrospectively selected and whole exome sequencing was performed on macrodissected lesions. DNA extraction, DNA quantification, library preparation and sequencing were performed with IDT xGen™ Exome Hybridization Panel v2 for library capture. Sequencing data was analyzed with an in-house bioinformatics pipeline for single-nucleotide variants and insertions/deletions.

RESULTS

All neonates were delivered at term and had birth weights ranging from 11th-35th percentile for gestational age. All mothers presented with hypertensive disorder during pregnancy. Chorangiomas ranged from 0.7 cm to 5.1 cm and were well-circumscribed near the fetal surface. Case 1 showed a background of chorangiosis and acute subchorionitis, while case 2 had foci of chronic lymphocytic villitis. Whole exome sequencing did not reveal any significant pathologic variants.

DISCUSSIONS

The absence of molecular alteration in placental chorangioma is likely indicative of the reactive/non-neoplastic nature of this lesion. The presence of compromised blood flow in the form of hypertensive disorders in our cases may be one of its underlying pathophysiologic mechanisms.

Placental Chorangiocarcinoma a Specific Histological Pattern of Uncertain Incidence and Clinical Impact: Systematic Review of the Literature

Chorangiocarcinoma is a very rare and misdiagnosed placental neoplasm. The unique morphologic features of the lesion distinguish it from other trophoblastic tumors and vascular abnormalities. We present a systematic review of the literature to provide clarity on chorangiocarcinoma entity and biology. A literature search was carried out in December 2022 using the keywords "Placental chorangiocarcinoma", "Chorangioma", "Placenta", and "Throphoblast proliferation". Articles published from 1988 to 2022 were obtained from Scopus, Google Scholar, and PUBMED. In our review, we examined maternal age, gestational age at the time of delivery, parity, type of pregnancy, placental weight, ultrasound features of the placenta, macroscopic examination and tumor size, microscopic examination, immunostaining, maternal beta-human chorionic gonadotropin, fetal and maternal outcome. Eight manuscripts were detected. They are all case reports. The macroscopic characteristics of the lesions were represented by the presence of a grey-yellow-white color well-demarcated round nodule. Microscopically, all the authors described typical aspects of malignancy as a high rate of mitosis, nuclear atypia and necrotic areas. In some cases, the presence of AE1/AE3 cytoplasmic positivity, p63 nuclear staining, and beta-human chorionic gonadotropin (BHCG) were reported. A good fetal outcome was reported in all cases of newborns with normal birth weight, except one with fetal growth restriction. Maternal outcome was good in all cases except one with maternal lung metastasis three months after delivery. The clinical course has probably underestimated the real incidence of the pathology. Only greater knowledge of its histology and its clinical course will allow us to evaluate the real prevalence of the disease.

Degenerative type of placental chorioangioma requiring fetal blood transfusion

We experienced a case with fetal hydrops, polyhydramnios, and a well-defined oval anechoic lesion of approximately 9 cm in size, without blood flow at 26 weeks' gestation. As increased middle cerebral artery peak systolic velocity, the fetal hydrops was caused by a placental tumor such as a chorioangioma; however, the tumor was atypical. Fetal blood hemoglobin was 8.3 g/dl on percutaneous umbilical cord blood sampling. After erythrocytes transfusion to the fetus, the mother normally delivered at 38 weeks' gestation. The placental tumor was histologically diagnosed as a necrotic chorioangioma. Obstetricians should note such atypical chorioangiomas when differential diagnosis of placental tumors.

Multiple Chorangioma Following Long-Term Secondary Infertility: A Rare Case Report and Review of Pathologic Differential Diagnosis

Chorangioma (placental hemangioma) is a benign non-trophoblastic neoplasm of the placenta. Small chorangiomas are usually asymptomatic, but the giant and multiple ones rarely have a favorable outcome. We report a case of 29 weeks of gestational age (after long-term secondary infertility) with premature labor pain and undiagnosed multiple chorangioma leading to hydrops fetalis and neonatal death. Here we report the clinicopathological features of our case and chorangioma in general, along with comparison of different vascular lesions of placenta in terms of incidence, risk factors, complications, histologic origin, macroscopic and light and electron microscopic features.

[Pseudosarcomatous chorangioma: A macroscopic and microscopic atypical tumor]

We report a case of an unusual chorangioma in a 26-year-old gravida 2, para 1 female. The clinical course was complicated by premature birth at 34 weeks' gestation. The baby presented with congenital cardiac and renal malformations. The tumor was 11 cm in size, separated from the main placental mass and exhibited atypical histologic characteristics such as fibromatous areas, high cellularity, nuclear atypia and high mitotic index. These histologic features must not be interpreted as malignancy.

Pseudotumors of the placenta

The placenta is one of the most common gross pathology specimens encountered by surgical pathologists, yet primary tumors are exceptionally rare and even rarer are entities with the potential to mimic malignancy. There are many nonneoplasticmass forming lesions in the placenta that are important to be aware of as many of these can be associated with adverse outcomes in the mother and fetus. Also important are entities which may be observed microscopically in the placenta and potentially confused as a malignancy. Knowledge of these potential pitfalls is essential to avoid making an incorrect diagnosis and causing undue alarm.