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.

Images in abnormal placenta: a rare case of "blood bag" formation in placenta membranacea.

Placenta membranacea is an uncommon placental anomaly. Here, we present the case of a 30-year-old primiparous woman admitted for thickened placenta and reduced amniotic fluid. A follow-up ultrasound, performed after 48 h, revealed that the placental parenchyma was thin and not adequately visualized, enclosing a substantial volume of flowing blood (150 mm), with an amniotic fluid index of 18 mm. An emergency cesarean section was promptly performed. Following fetal delivery, a substantial accumulation of dark red blood within the fetal membranes created a "blood bag", estimated at approximately 3000 ml. This observation aligned with the ultrasound findings, and both placental morphology and pathological results substantiated the diagnosis of placenta membranacea.

Placenta accreta spectrum disorder at single-cell resolution: a loss of boundary limits in the decidua and endothelium.

BACKGROUND: Placenta accreta spectrum disorders are associated with severe maternal morbidity and mortality. Placenta accreta spectrum disorders involve excessive adherence of the placenta preventing separation at birth. Traditionally, this condition has been attributed to excessive trophoblast invasion; however, an alternative view is a fundamental defect in decidual biology. OBJECTIVE: This study aimed to gain insights into the understanding of placenta accreta spectrum disorder by using single-cell and spatially resolved transcriptomics to characterize cellular heterogeneity at the maternal-fetal interface in placenta accreta spectrum disorders. STUDY DESIGN: To assess cellular heterogeneity and the function of cell types, single-cell RNA sequencing and spatially resolved transcriptomics were used. A total of 12 placentas were included, 6 placentas with placenta accreta spectrum disorder and 6 controls. For each placenta with placenta accreta spectrum disorder, multiple biopsies were taken at the following sites: placenta accreta spectrum adherent and nonadherent sites in the same placenta. Of note, 2 platforms were used to generate libraries: the 10× Chromium and NanoString GeoMX Digital Spatial Profiler for single-cell and spatially resolved transcriptomes, respectively. Differential gene expression analysis was performed using a suite of bioinformatic tools (Seurat and GeoMxTools R packages). Correction for multiple testing was performed using Clipper. In situ hybridization was performed with RNAscope, and immunohistochemistry was used to assess protein expression. RESULTS: In creating a placenta accreta cell atlas, there were dramatic difference in the transcriptional profile by site of biopsy between placenta accreta spectrum and controls. Most of the differences were noted at the site of adherence; however, differences existed within the placenta between the adherent and nonadherent site of the same placenta in placenta accreta. Among all cell types, the endothelial-stromal populations exhibited the greatest difference in gene expression, driven by changes in collagen genes, namely collagen type III alpha 1 chain (COL3A1), growth factors, epidermal growth factor-like protein 6 (EGFL6), and hepatocyte growth factor (HGF), and angiogenesis-related genes, namely delta-like noncanonical Notch ligand 1 (DLK1) and platelet endothelial cell adhesion molecule-1 (PECAM1). Intraplacental tropism (adherent versus non-adherent sites in the same placenta) was driven by differences in endothelial-stromal cells with notable differences in bone morphogenic protein 5 (BMP5) and osteopontin (SPP1) in the adherent vs nonadherent site of placenta accreta spectrum. CONCLUSION: Placenta accreta spectrum disorders were characterized at single-cell resolution to gain insight into the pathophysiology of the disease. An atlas of the placenta at single cell resolution in accreta allows for understanding in the biology of the intimate maternal and fetal interaction. The contributions of stromal and endothelial cells were demonstrated through alterations in the extracellular matrix, growth factors, and angiogenesis. Transcriptional and protein changes in the stroma of placenta accreta spectrum shift the etiologic explanation away from "invasive trophoblast" to "loss of boundary limits" in the decidua. Gene targets identified in this study may be used to refine diagnostic assays in early pregnancy, track disease progression over time, and inform therapeutic discoveries.

Stillbirth and the placenta.

Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been identified and include obstetrical complications, placental abnormalities, fetal malformations, infections, and medical complications in pregnancy. Placental abnormalities such as placental abruption, chorioangioma, vasa previa, and umbilical cord abnormalities have been identified as causes of death for a significant proportion of stillbirths. In the absence of placental abnormalities, the gross and histologic changes in the placenta in stillbirth are found when secondary to other etiologies. Here we describe both gross and histologic changes of the placenta that are associated with stillbirth.

A novel technique to estimate intravillous fetal vasculature on routine placenta histologic sections.

Placental histopathologic lesions are dichotomized into "present" or "absent" and have limited inter-rater reliability. Continuous metrics are needed to characterize placental health and function. Tissue sections (N = 64) of human placenta were stained with CD34 antibody and hematoxylin. Proportion of the villous space occupied by fetal vascular endothelium (%FVE; pixels positive for CD34/total pixels) was evaluated for effect sizes associated with pregnancy outcomes, smoking status, and subtypes of lesions (n = 30). Time to fixation>60 min significantly increased the quantification. Large effect sizes were found between %FVE and both preterm birth and intrauterine growth restriction. These results demonstrate proof-of-concept for this vascular estimation.

Metastatic Lymphomas of the Placenta: A Literature Review With an Illustrative Case.

Lymphoma is the fourth most common tumor to display placental metastasis. This study aimed to report a case of high-grade lymphoma involving the placenta and review the literature on lymphomas metastatic to the placenta. A systematic review was performed following the PRISMA guidelines, using the keywords "lymphoma" AND "placenta." All case reports and case series on lymphoma infiltrating the placenta were collected. Eight cases from 7 studies, including the present case, were synthesized. The mean patient age is 29.5 years. The clinical presentation is non-specific. Hematologic derangements included cytopenias or cytoses, and elevated prothrombin time. The mean gestational age (GA) when a diagnosis of lymphoma was rendered is 27 weeks. Five cases presented with either lymphadenopathy or visceral masses on imaging. Four of these cases eventually led to maternal demise. The mean GA when the fetus was delivered is 31 3/4 weeks. Grossly, most placentas had non-specific findings. Leukemic infiltrates were mostly seen within intervillous spaces. Intravillous infiltrates were associated with high-grade lymphomas, resulting in either maternal demise or stillborn fetuses. This study suggests that the placenta has mechanisms to guard against malignancies; however, these defense mechanisms are not foolproof and may be breached by tumor cells.

Maternal and fetal outcomes of intraplacental choriocarcinoma complicated by fetomaternal hemorrhage: a systematic review.

INTRODUCTION: Intraplacental choriocarcinoma is a gestational trophoblastic neoplasia located within the placenta. Due to the usual silent presentation, more than half of the cases are diagnosed incidentally. It has been demonstrated that this pathology is linked to feto-maternal hemorrhage (FMH), stillbirth, and intrauterine growth restriction. The aim of our review was to establish if there are recurrent signs that might lead to an early diagnosis and better management in cases complicated by FMH. MATERIALS AND METHODS: We performed a systematic review of the literature from 2000 up to March 2023. The adopted research strategy included the following terms: (gestational choriocarcinoma obstetrics outcome) AND (intraplacental choriocarcinoma) AND (gestational choriocarcinoma). The MEDLINE (PubMed), Google Scholar, and Scopus databases were searched. RESULTS: The research strategy identified 19 cases of FMH coexisting with intraplacental choriocarcinoma (IC), as described in 17 studies. The perinatal mortality rate was 36.8%. In eight cases, histological diagnosis of IC was made post-delivery. Metastatic lesions were found in 75% (6/8) of described cases. One case of maternal death has been described. Chemotherapy was necessary in seven cases. Sporadical prenatal ultrasound signs were described. DISCUSSION: The diagnosis of IC is usually delayed, mostly due to aspecific symptoms and signs. Histological analysis of the placenta, when not routinely performed, should be performed when warning symptoms are encountered. The maternal prognosis was good, with a mortality rate of 5.5%. A fertility-sparing approach is always possible even in the presence of metastasis. Chemotherapy seems to be useful in cases of maternal and neonatal metastasis.

The impact of polycystic ovary syndrome on placental histopathology patterns in in-vitro fertilization singleton live births.

INTRODUCTION: Pregnant polycystic ovary syndrome (PCOS) patients are at increased risk for myriad obstetric complications, with the placenta thought to play a key role in their development. We aimed to evaluate placental histopathology patterns in placentas of women with PCOS who underwent in-vitro-fertilization (IVF). METHODS: This retrospective study utilized full gross and histopathologic assessment of placentas of all women who had IVF treatment and delivered at the Royal Victoria Hospital from 2009 to 2017, regardless of complications or mode of delivery. Pathologic findings included anatomic, inflammation, villous maturation, and vascular mal-perfusion features. Placentas of PCOS women were compared to those of ovulatory controls. Multivariate logistic regression was used to adjust results for confounding factors potentially associated with significant placental and perinatal characteristics. RESULTS: Women with PCOS (n = 47) were more likely to develop gestational diabetes mellitus compared to ovulatory controls (n = 1121) (38.3% vs. 9.8%, p < 0.001). Placentas from PCOS women were more likely circumvallate placentas (aOR 8.3, 95%CI 1.9-37.3) and more likely to have a hypercoiled umbilical cord (aOR 6.8 95%CI 1.3-36.8) and villitis of unknown etiology (aOR 6.1, 95%CI 1.5-25.6). There was an increased likelihood of chorangiosis (aOR 2.7, 95% CI 1.3-5.8), evidence of fetal vascular malperfusion based on one criteria (aOR 2.7, 95%CI 1.1-7.4), or more than one criteria (aOR 6.4, 95%CI 1.6-25.9), more nucleated fetal red blood cells (aOR 5.2, 95%CI 1.1-24.5), and a higher likelihood of chorangiomas (aOR 9.4, 95%CI 1.6-55.1) in placentas from PCOS women than in controls. DISCUSSION: IVF pregnancies' placental histopathological characteristics are significantly impacted by an underlying diagnosis of PCOS, including important anatomic changes and vascular placental abnormalities.

Misdiagnosis of placental mesenchymal dysplasia as pregnancy with hydatidiform mole: A case report and literature review.

RATIONALE: Placental mesenchymal dysplasia (PMD) is a rare placental disease frequently associated with severe maternal and/or fetal complications. Its sonographic appearance is very similar to that of a hydatidiform mole. Hence, PMD is easily misdiagnosed as a hydatidiform mole. In this study, we reported the clinical features of PMD and analyzed its relationship to other severe maternal and/or fetal complications. PATIENT CONCERNS: A 28-year-old female, gravida 2, para 1, was referred to our maternal and child health hospital at 15 weeks + 2 days due to an ultrasonic diagnosis of partial hydatidiform mole. Analysis of chromosome karyotype + mononucleotide-based gene microarray by amniocentesis at the 19th week of gestation showed that fetal amniocentesis chromosome 46, XN, high-resolution chromosome microarray analysis of Affymetrix CytoScan 750K Array revealed a 210 kb fragment deletion in chromosome 2p16.3 containing NRXN1, an OMIM gene, the deleted fragment was derived from a mother with a normal phenotype. The pregnant woman delivered a healthy baby girl at 36 weeks + 5 days. DIAGNOSES: Based on the clinical characteristics, imaging, and genetic test findings, the postoperative diagnosis was PMD. INTERVENTION: Because of "Scar uterus" and "Pregnancy with hydatidiform mole," a 2490 g female infant was delivered by cesarean section at 36 weeks + 5 days of gestation with an Apgar score of 9/9. OUTCOMES: The maternal human chorionic gonadotropin level decreased to the normal range after 10 days of delivery, and the infant was not found abnormal after 3 months of follow-up. LESSONS: From our cases and 19 other cases obtained from the PMD literature review are associated with unique clinical, laboratory, and imaging features compared with a hydatidiform mole, such as stained glass sign, normal serum levels of serum human chorionic gonadotropin, elevated alpha-fetoprotein levels and female fetus.

Machine learning classification of placental villous infarction, perivillous fibrin deposition, and intervillous thrombus.

INTRODUCTION: Placental parenchymal lesions are commonly encountered and carry significant clinical associations. However, they are frequently missed or misclassified by general practice pathologists. Interpretation of pathology slides has emerged as one of the most successful applications of machine learning (ML) in medicine with applications ranging from cancer detection and prognostication to transplant medicine. The goal of this study was to use a whole-slide learning model to identify and classify placental parenchymal lesions including villous infarctions, intervillous thrombi (IVT), and perivillous fibrin deposition (PVFD). METHODS: We generated whole slide images from placental discs examined at our institution with infarct, IVT, PVFD, or no macroscopic lesion. Slides were analyzed as a set of overlapping patches. We extracted feature vectors from each patch using a pretrained convolutional neural network (EfficientNetV2L). We trained a model to assign attention to each vector and used the attentions as weights to produce a pooled feature vector. The pooled vector was classified as normal or 1 of 3 lesions using a fully connected network. Patch attention was plotted to highlight informative areas of the slide. RESULTS: Overall balanced accuracy in a test set of held-out slides was 0.86 with receiver-operator characteristic areas under the curve of 0.917-0.993. Cases of PVFD were frequently miscalled as normal or infarcts, the latter possibly due to the perivillous fibrin found at the periphery of infarctions. We used attention maps to further understand some errors, including one most likely due to poor tissue fixation and processing. DISCUSSION: We used a whole-slide learning paradigm to train models to recognize three of the most common placental parenchymal lesions. We used attention maps to gain insight into model function, which differed from intuitive explanations.

Fetal and placental metastases associated with maternal cancers.

PURPOSE: Review the effects of fetal and placental metastases in the setting of maternal cancer. METHOD: Data reported in the peer-reviewed literature were combined with guidelines to evaluate the incidence, type and prognosis for fetal and placental metastasis in the setting of maternal cancer. RESULTS: Limited literature available. Fetal and placental metastasis are rare. Fetal metastasis generally occurs on the background of concurrent placental metastasis thus it is important to thoroughly examine the placenta in cases of known gestational cancers. Tumor molecular testing is used to confirm maternal to offspring transmission. Maternal to offspring transmission may have a long timeline between birth to clinical presentation. Prognosis in offspring may be better than in the mother who may have a more aggressive phenotype. CONCLUSION: Fetal and placental metastasis associated with maternal cancers are rare and limited peer-reviewed literature is available. The occurrence may be confirmed by detailed histological placental evaluation and molecular testing in the offspring.

Mutation of the TP53 Gene in Placental Chorangiomatosis.

Objective: We explored the frequency of TP53 gene mutations in chorangiomas (CA) and chorangiomatosis (CM). Materials and -methods: By Sanger sequencing, we evaluated mutations in exons 4-6 of the TP53 gene in CM and CA regions of placentas. Results: In total, 7/11(63.6%) CAs and 24/26 (92.3%) CMs had TP53 mutations, with a significantly higher frequency in the latter. Mutations in both groups predominately involved exon 4, most commonly at the 119th C. The mutation types at the 119th C were C/G and G/G. Among the patients with exon 4 mutations at the 119th C, C/G mutations, the most common type, were observed more frequently in the CM group (63.16%, 12/19) than in the CA group (14.29%, 1/7), and the difference was significant. Conclusion: It is suggested that both CM and CA are tumors rather than tumor-like lesions. Although they are histologically similar, they have a different TP53 profile.

Intrauterine Fetal Demise Associated with Vascular Malperfusion and Multiple Uterine Leiomyomata: A Report of Two Cases.

BACKGROUND: Uterine leiomyomata have been loosely associated with intrauterine fetal demise (IUFD), largely attributed to fetal growth restriction from cavitary distortion. We present two cases of IUFD in patients with non-distorting leiomyomata and pathologic placental findings of maternal vascular malperfusion (MVM) and fetal vascular malperfusion (FVM). CASE REPORT: Case 1 details a 28w3d IUFD associated with large leiomyomata (largest 11.9 × 7.6 × 9.7 cm), post-partum deep vein thrombosis, and severe pre-eclampsia histologic features. Case 2 details a 25w2d IUFD associated with smaller leiomyomata (largest 3.1 × 3.0 × 3.3 cm). Both placentas demonstrated MVM, including parenchymal thrombi and accelerated villous maturity, and FVM, including avascular stem villi. DISCUSSION: As the placentas in both cases demonstrated findings consistent with altered placental perfusion, we posit that leiomyomata in these cases may have been associated with both maternal and fetal vascular malperfusion, ultimately contributing to fetal demise.

Placental interferon signaling is involved in chronic intervillositis of unknown etiology.

INTRODUCTION: Chronic intervillositis of unknown etiology (CIUE) is a placental inflammatory process associated with pregnancy loss and high recurrence risk. The pathogenesis is unclear but involves aberrant maternal inflammation. This study assesses expression of inflammatory mediators by placenta and intervillus macrophage using digital spatial profiling, which is applicable to formalin fixed paraffin embedded tissue and provides whole transcriptome expression analysis at cellular resolution. METHODS: Ethics approval was obtained and all experiments were performed in accordance with applicable guidelines and regulations. Archival tissue from early spontaneous pregnancy loss with high grade CIUE (4 cases) was compared to non-inflamed control normal placenta (4 cases) and granulomatous lymphadenitis as a macrophage inflammation control (4 cases). Differential gene expression between CIUE and relevant controls was assessed using unpaired t-test with Benjamini-Hochberg false discovery correction. Gene Set Enrichment Analysis (GSEA) was used to characterize and compare pathways active in the CIUE and relevant control samples. RESULTS: Principal component analysis of the gene expression data showed distinct clustering with relatively little intragroup variation in the control tissues whereas the CIUE cases are more variable. Gene expression analysis showed changes in CIUE; however, no genes remained statistically significant after correction for false discovery. GSEA revealed prominent activation of IFN-related signaling pathways in CIUE placenta, particularly IFNγ signaling. DISCUSSION: This study demonstrates that CIUE is associated with a specific profile of inflammatory mediators expressed by placenta villi that is dominated by IFN signaling, suggesting that uncontrolled IFNγ signaling may play a primary role in the pathogenetic mechanism underlying CIUE.

Regulation of Proinflammatory Molecules and Tissue Factor by SARS-CoV-2 Spike Protein in Human Placental Cells: Implications for SARS-CoV-2 Pathogenesis in Pregnant Women.

SARS-CoV-2 infects cells via binding to ACE2 and TMPRSS2, which allows the virus to fuse with host cells. The viral RNA is detected in the placenta of SARS-CoV-2-infected pregnant women and infection is associated with adverse pregnancy complications. Therefore, we hypothesize that SARS-CoV-2 infection of placental cells induces pro-inflammatory cytokine release to contribute to placental dysfunction and impaired pregnancy outcomes. First, expression of ACE2 and TMPRSS2 was measured by qPCR in human primary cultured term cytotrophoblasts (CTBs), syncytiotrophoblast (STBs), term and first trimester decidual cells (TDCs and FTDCs, respectively), endometrial stromal cells (HESCs) as well as trophoblast cell lines HTR8, JEG3, placental microvascular endothelial cells (PMVECs) and endometrial endothelial cells (HEECs). Later, cultured HTR8, JEG3, PMVECs and HEECs were treated with 10, 100, 1000 ng/ml of recombinant (rh-) SARS-CoV-2 S-protein ± 10 ng/ml rh-IFNγ. Pro-inflammatory cytokines IL-1ß, 6 and 8, chemokines CCL2, CCL5, CXCL9 and CXCL10 as well as tissue factor (F3), the primary initiator of the extrinsic coagulation cascade, were measured by qPCR as well as secreted IL-6 and IL-8 levels were measured by ELISA. Immunohistochemical staining for SARS-CoV-2 spike protein was performed in placental specimens from SARS-CoV-2-positive and normal pregnancies. ACE2 levels were significantly higher in CTBs and STBs vs. TDCs, FTDCs and HESCs, while TMPRSS2 levels were not detected in TDCs, FTDCs and HESCs. HTR8 and JEG3 express ACE2 and TMPRSS2, while PMVECs and HEECs express only ACE2, but not TMPRSS2. rh-S-protein increased proinflammatory cytokines and chemokines levels in both trophoblast and endothelial cells, whereas rh-S-protein only elevated F3 levels in endothelial cells. rh-IFNγ ± rh-S-protein augments expression of cytokines and chemokines in trophoblast and endothelial cells. Elevated F3 expression by rh-IFNγ ± S-protein was observed only in PMVECs. In placental specimens from SARS-CoV-2-infected mothers, endothelial cells displayed higher immunoreactivity against spike protein. These findings indicated that SARS-CoV-2 infection in placental cells: 1) induces pro-inflammatory cytokine and chemokine release, which may contribute to the cytokine storm observed in severely infected pregnant women and related placental dysfunction; and 2) elevates F3 expression that may trigger systemic or placental thrombosis.

Early pathways, biomarkers, and four distinct molecular subclasses of preeclampsia: The intersection of clinical, pathological, and high-dimensional biology studies.

Preeclampsia is a syndromic disease of the mother, fetus, and placenta. The main limitation in early and accurate diagnosis of preeclampsia is rooted in the heterogeneity of this syndrome as reflected by diverse molecular pathways, symptoms, and clinical outcomes. Gaps in our knowledge preclude successful early diagnosis, personalized treatment, and prevention. The advent of "omics" technologies and systems biology approaches addresses this problem by identifying the molecular pathways associated with the underlying mechanisms and clinical phenotypes of preeclampsia. Here, we provide a brief overview on how the field has progressed, focusing on studies utilizing state-of-the-art transcriptomics and proteomics methods. Moreover, we summarize our systems biology studies involving maternal blood proteomics and placental transcriptomics, which identified early maternal and placental disease pathways and showed that their interaction influences the clinical presentation of preeclampsia. We also present an analysis of maternal blood proteomics data which revealed distinct molecular subclasses of preeclampsia and their molecular mechanisms. Maternal and placental disease pathways behind these subclasses are similar to those recently reported in studies on the placental transcriptome. These findings may promote the development of novel diagnostic tools for the distinct subtypes of preeclampsia syndrome, enabling early detection and personalized follow-up and tailored care of patients.

Atherosis of Trophoblast Type: A Specific Form of Decidual Vasculopathy Distinct From Atherosis of Macrophage Type.

CONTEXT.­: There are 3 types of decidual vasculopathy, namely, acute atherosis, fibrinoid medial necrosis, and mural arterial hypertrophy. Persistence of vascular trophoblasts is also known to be related to maternal vascular malperfusion, but detailed study is lacking. OBJECTIVE.­: To define atherosis of trophoblast type and distinguish it from atherosis of macrophage type with clinical significance. DESIGN.­: A total of 1322 placentas from 2021 were collected with clinical, neonatal, and placental information, and routine placental pathology examination was performed. Decidual vasculopathy was classified on the basis of the new classification scheme including atherosis of macrophage type, atherosis of trophoblast type, fibrinoid medial necrosis, mural arterial hypertrophy, and mixed-type vasculopathy. The significance of these morphologic changes was examined on the basis of clinical, neonatal, and placental pathology features. RESULTS.­: Decidual vasculopathy is classified as classic type, mural hypertrophy, and mixed type. Classic-type vasculopathy is further separated as atherosis and fibrinoid medial necrosis. Atherosis is defined as atherosis of macrophage type and atherosis of trophoblast type. Each category of decidual vasculopathy was evaluated in association with maternal, neonatal, and placental pathologic findings. Atherosis of macrophage type and mixed-type vasculopathy showed statistically significant association with preeclampsia/pregnancy-induced hypertension, low birth weight, and low placental weight. Atherosis of trophoblast type was associated with lower placental weight but not with other specific clinical features. Neonates of female sex were associated with mural arterial hypertrophy. CONCLUSIONS.­: Atherosis of trophoblast type is a distinct pathologic feature in late pregnancy, and it is associated with lower placental weight. New classification of decidual vasculopathy helps with better stratification and categorization of placental maternal vascular abnormalities of late pregnancy.

Prenatal Diagnosis of Placental Mesenchymal Dysplasia with 46, X, Isochromosome Xq/45, X Mosaicism.

Placental mesenchymal dysplasia is an uncommon vascular anomaly of the placenta with characteristics of placentomegaly and multicystic appearance and with or without association with fetal chromosomal anomaly. We present a unique placental mesenchymal dysplasia patient with amniotic fluid karyotyping as 46, X, iso(X) (q10). Detailed molecular testing of the amniotic fluid, fetal cord blood, non-dysplastic placenta and dysplastic placenta was conducted after termination of pregnancy, from which we proved biparental/androgenetic (46, X, i(X) (q10)/45, X) mosaicism in different gestational tissues. A high portion of androgenetic cells in dysplastic placenta (74.2%) and near 100% of biparental cells in the fetus's blood and amniotic fluid were revealed. Delicate mosaic analyses were performed, and possible pathogenesis and embryogenesis of this case were drawn up.

Clinicopathological characteristics of placental chorioangioma: A clinicopathological study of 77 cases.

OBJECTIVE: To explore clinicopathological characteristics, diagnosis, differential diagnoses, treatment, and prognoses of placental chorioangioma (PCA). METHODS: Placenta of 77 cases of PCA firmly diagnosed by pathology from 2009 through 2019 were collected, and clinicopathological characteristics of the patients were retrospectively analyzed. RESULTS: Seventy-seven patients were 20-41 (mean age, 28.8) years old at onset. Thirty patients showed pregnancy comorbidity. In one patient with the largest tumor (diameter, 16 cm), intrauterine fetal demise occurred at 33 weeks of gestation. Tumors were macroscopically manifested. The placental fetal surface showed a raised dark red to a pale pink nodule, quasi-round, with a maximum diameter of 0.2-16 cm. Microscopically, the tumors had a lot of capillaries and some interstitial loose connective tissue. One case was of atypical cellular chorioangioma. Immunophenotypically, CD34 (+) and Ki-67 proliferation indexes were less than 10%. CONCLUSIONS: Large PCA often accompanies pregnancy comorbidity. Atypical cellular chorangioma is rare and may be misdiagnosed as a malignant tumor. Therefore, improvement of understanding of such tumors can provide a basis for clinical diagnosis and intervention.

Hepatic and Adrenocortical Choristomas in the Placenta.

Background Hepatic and adrenocortical choristomas are unusual findings in the placenta. This meta-analysis includes our own case report and 23 previously reported cases. We searched for patterns of associated placental, fetal and maternal aberrations in order to determine whether these choristomas are clinically relevant. Case report: In our case, abortion was induced due to fetal central nervous system and renal malformations. In the placenta a hepatic choristoma (<0.1 cm), thrombangiitis obliterans and a single umbilical artery were found. Results: In the literature, the majority of lesions were ≤1.0 cm (n = 21/24, 87.5%) and two hepatic choristomas manifested within chorangiomas. In a subfraction of cases, we found an association with twin/triple pregnancies (n = 6/24, 25%) and heterogeneous non-hepatic/non-adrenal malformations in fetuses (n = 4/24, 17%). Conclusion: Hepatic and adrenocortical choristomas are benign, could be based on focal epigenetic changes and might be related to chorangiomas but are not associated with a particular disease pattern or risk profile.