Single-nucleotide polymorphism array and fluorescence in situ hybridization analysis to decode the cytogenetic profile of atypical partial hydatidiform moles diagnosed by short tandem repeat polymorphism analysis.

Accurate diagnosis of partial hydatidiform moles (PHMs) is crucial for improving outcomes of gestational trophoblastic neoplasia. The use of short tandem repeat (STR) polymorphism analysis to distinguish between PHM and hydropic abortuses is instrumental; however, its diagnostic power has not been comprehensively assessed. Herein, we evaluated the diagnostic efficacy of STR in differentiating between PHM and hydropic abortus, thus providing an opportunity for early measurement of human chorionic gonadotropin for PHMs. We reviewed charts of STR polymorphism analysis performed on fresh villous specimens and patient blood samples using a commercial kit for 16 loci. The genetic classification of 79 PHMs was confirmed. STR was reliable in differentiating PHMs when at least 15 loci were available. Typically, PHMs are characterized by their triploidy, including two paternal and one maternal haploid contribution. In our sample, seven PHMs lacked the three-allelic loci, requiring fluorescence in situ hybridization (FISH) analysis to investigate imbalanced biparental conceptus and single-nucleotide polymorphism array analysis to reveal cytogenetic details. Of these PHMs, two, three, and one were identified as androgenetic/biparental mosaics (diploids), monospermic diandric monogynic triploids, and a typical dispermic diandric monogynic triploid, respectively. The remaining case was monospermic origin, but its ploidy details could not be available. Therefore, STR differentiated PHM from a biparental diploid abortus in most cases. However, PHM diagnosis may be compromised when STR is used as the sole method for cases displaying distinct cytogenetic patterns lacking the three-allelic loci, including androgenetic/biparental mosaicism. Therefore, FISH should be considered to confirm the diagnosis.

Evaluation of Combined p57KIP2 Immunohistochemistry and Fluorescent in situ Hybridization Analysis for Hydatidiform Moles Compared with Genotyping Diagnosis.

Immunostaining with p57KIP2 is a widely used diagnostic technique to differentiate complete hydatidiform moles (CHMs) from partial hydatidiform moles (PHM) and non-molar hydropic abortion. However, distinguishing between PHMs and non-molar hydropic abortions using histopathology alone is often challenging. This study aimed to evaluate the technical validity and additional benefits of using fluorescence in situ hybridization (FISH) in combination with p57KIP2 immunostaining to diagnose molar and non-molar conceptuses. The study involved 80 specimens, which underwent genetic diagnosis using short tandem repeat analysis, including 44 androgenetic CHMs, 20 diandric monogynic PHMs, 14 biparental non-molar hydropic abortions, 1 monoandric digynic triploid abortion, and 1 vaginal specimen of gestational trophoblastic neoplasia. Two pathologists independently diagnosed the cases based on morphology and p57KIP2 immunostaining while the clinical information was masked. FISH analysis was performed using 3 probes (CEP17, CEPX, and CEPY), which revealed that all androgenetic CHM and biparental diploid non-molar hydropic abortion specimens were diploid. Among the 20 diandric monogynic PHM cases examined by analyzing short tandem repeat polymorphisms, 18 were triploid, and the remaining 2 were diploid. These two specimens were possibly androgenetic/biparental mosaics based on FISH analysis, where the three-signal ratios counting 50 cells were clearly within the diploid ranges. Eight of the 20 genetic PHMs and 2 of the 14 genetically confirmed non-molar hydropic abortions that were falsely diagnosed based on morphology and immunohistochemistry by at least 1 pathologist were correctly diagnosed as PHM and non-molar hydropic abortion, respectively, by FISH analysis. However, 1 monoandric digynic villus was classified as triploid by FISH analysis, leading to a false PHM diagnosis. In conclusion, the combination of FISH analysis with p57KIP2 immunostaining helps in diagnosing molar and non-molar conceptuses in numerous cases; nevertheless, exceptional cases should be considered.

Intrauterine hydatidiform mole complicated with tubal ectopic pregnancy: a case report.

Heterotopic pregnancies are rare pathological pregnancy disorders in clinical practice. However, the number of cases has increased with the widespread use of ovulation induction drugs in recent years. The clinical manifestations of heterotrophic pregnancies are diverse and easy to missed or misdiagnosed. A 33-year-old married Gravida1 Para 0 + 0 patient was admitted on December 8, 2020 with intermittent abdominal pain 18 days after uterine curettage for complete hydatidiform mole of 8 weeks gestation. She had ovulation-promoting drugs prior to the index pregnancy. Hysteroscopic-directed endometrial biopsy and laparoscopic left tubal surgery were offered to her; and she is being followed up with serial pelvic ultrasounds and ß-Human Chorionic Gonadotrophin (ßHCG) assays. This case study presents a case of intrauterine hydatidiform mole complicated with tubal pregnancy to highlight the problems associated with its diagnosis and treatment.

Diagnostic Utility of TSSC3 and RB1 Immunohistochemistry in Hydatidiform Mole.

The general notion of complete hydatidiform moles is that most of them consist entirely of paternal DNA; hence, they do not express p57, a paternally imprinted gene. This forms the basis for the diagnosis of hydatidiform moles. There are about 38 paternally imprinted genes. The aim of this study is to determine whether other paternally imprinted genes could also assist in the diagnostic approach of hydatidiform moles. This study comprised of 29 complete moles, 15 partial moles and 17 non-molar abortuses. Immunohistochemical study using the antibodies of paternal-imprinted (RB1, TSSC3 and DOG1) and maternal-imprinted (DNMT1 and GATA3) genes were performed. The antibodies' immunoreactivity was evaluated on various placental cell types, namely cytotrophoblasts, syncytiotrophoblasts, villous stromal cells, extravillous intermediate trophoblasts and decidual cells. TSSC3 and RB1 expression were observed in all cases of partial moles and non-molar abortuses. In contrast, their expression in complete moles was identified in 31% (TSSC3) and 10.3% (RB1), respectively (p < 0.0001). DOG1 was consistently negative in all cell types in all cases. The expressions of maternally imprinted genes were seen in all cases, except for one case of complete mole where GATA3 was negative. Both TSSC3 and RB1 could serve as a useful adjunct to p57 for the discrimination of complete moles from partial moles and non-molar abortuses, especially in laboratories that lack comprehensive molecular service and in cases where p57 staining is equivocal.

DNA analysis of partial hydatidiform mole revealing triandric monogynic tetraploidy.

The authors present a case of a partial hydatidiform mole where DNA analysis (STR - short tandem repeat genotyping) showed a triandric monogynic tetraploid genome composition with a XXXY gonosomal complement. This genetic finding clinicopathologically correlates with a partial hydatidiform mole, although it is rare in comparison with the typical, diandric monogynic triploid partial moles. The genetic analysis definitively confirmed the suspected diagnosis of a partial mole. To exclude the possibility that molar pregnancy represented retained products of conception after elective pregnancy termination, STR profiles from molar pregnancy and previous products of conception were compared. Short tandem repeats genotyping is a useful molecular genetic method in the differential diagnosis of partial hydatidiform moles, where clinical-pathological findings are frequently ambiguous.

Complete hydatidiform mole with a coexisting foetus of term pregnancy: A case report and review of the literature.

A case of a complete mole with a full term live foetus misdiagnosed as placental mesenchymal dysplasia prenatally is being reported here. The infant was delivered at term, and the placenta was accompanied with molar changes. Both the mother and baby were healthy with no complications at one-year follow-up. This report systematically summarises identification methods to reduce the rate of misdiagnosis for better pregnancy outcomes.

Immunohistochemical expression of BCL-2 in hydatidiform moles: a tissue microarray study.

Background: Hydatidiform moles (HM) are members of gestational trophoblastic diseases (GTD) and, in some cases, might progress to gestational trophoblastic neoplasia (GTN). HMs are either partial (PHM) or complete (CHM). Some HMs are challenging in arriving at a precise histopathological diagnosis. This study aims to investigate the expression of BCL-2 by immunohistochemistry (IHC) in HMs as well as in normal trophoblastic tissues "products of conception (POC) and placentas" using Tissue MicroArray (TMA) technique. Methods: TMAs were constructed using the archival material of 237 HMs (95 PHM and 142 CHM) and 202 control normal trophoblastic tissues; POC and unremarkable placentas. Sections were immunohistochemically stained using antibodies against BCL-2. The staining was assessed semi-quantatively (intensity and percentage of the positive cells) in different cellular components (trophoblasts and stromal cells). Results: BCL-2 showed cytoplasmic expression in more than 95% of trophoblasts of PHM, CHM and controls. The staining showed a significant reduction of the intensity from controls (73.7%), PHMs (76.3%) to CHM (26.9%). There was a statistically significant difference between PHM and CHM in the intensity (p-value 0.0005) and the overall scores (p-value 0.0005), but not the percentage score (p-value > 0.05). No significant difference was observed in the positivity of the villous stromal cells between the different groups. All cellular components were visible using the TMA model of two spots/case (3 mm diameter, each) in more than 90% of cases. Conclusions: Decreased BCL-2 expression in CHM compared to PHM and normal trophoblasts indicates increased apoptosis and uncontrolled trophoblastic proliferation. Construction of TMA in duplicates using cores of 3 mm diameter can overcome tissue heterogeneity of complex lesions.

Hydatidiform mole.

Hydatidiform mole is the most common form of gestational trophoblastic disease. It is an abnormally formed placental tissue with characteristic changes in karyotype, arising in fertilization disorders. The presence of abundant paternal genetic information plays a key role in the pathogenesis of complete and partial hydatidiform moles. These lesions are characterized by a relatively wide spectrum of morphological changes that may not be fully expressed, especially in the early stages of pregnancy. In addition, some changes can be observed in non-molar gravidities, which, unlike hydatidiform moles, lack any risk of malignant transformation. Although conventional histological examination still plays a key role in the diagnosis, it should be supplemented by other methods that reliably differentiate individual lesions. Accurate diagnosis of molar gravidities is important not only for determining the correct therapeutic approach, but the obtained data may also contribute to further research of these pathological entities.

Molecular diagnosis of complete and partial hydatidiform moles.

Complete and partial hydatidiform moles are abnormal products of conception that can be identified by clinical, ultrasonographic, morphologic, histologic, and genetic methods. The diagnosis is usually confirmed only by histological examination. However, accurate diagnosis based on morphological criteria is difficult and some studies have shown that misclassifications are common, even when analysed by highly experienced pathologists. Misdiagnosis may mean that women are either not included in adequate ß-hCG follow-up with the risk that the hydatidiform mole progresses to choriocarcinoma or, conversely, are included in follow-up unnecessarily. A reliable complementary method to pathological interpretation may be genetic analysis of the conceptus to eliminate the diagnostic dilemma by distinguishing non-molar spontaneous abortions from hydatidiform moles and defining the type of hydatidiform mole. The aim of our short paper is to introduce the routine molecular analysis used in our laboratory to a wider range of clinical pathologists.

Gestational trophoblastic disease- rare, sometimes dramatic, and what we know so far.

Gestational trophoblastic disease (GTD) is a heterogeneous group of lesions that are characterized by the abnormal proliferation of the trophoblast. Morphology, behavior and clinical significance vary tremendously and range from benign, non-neoplastic lesions that cause sometimes dysfunctional uterine bleeding to aggressive, highly, malignant tumors. The recently updated 2020 World Health Organization (WHO) Classification of Female Genital Tumors divides GTD in molar pregnancies/ hydatidiform moles, gestational trophoblastic neoplasms, tumor-like lesions and abnormal (nonmolar) villous lesions. In this article we review the typical clinical presentations of GTDs, their histopathologic features, contributing immunohistochemical stains and current diagnostic criteria. We discuss novel insights in the proposed pathogenesis, newly proposed entities and advances in ancillary diagnostic techniques and their relevance to the histopathologic diagnosis of GTD. Additionally we briefly review current treatment options, prognosis and prognostic factors of GTDs.

Auxiliary and experimental diagnostic techniques for hydatidiform moles.

Hydatidiform moles are classified into complete hydatidiform moles (CHMs), which are androgenetic and diploid, and partial hydatidiform moles (PHM), which are triploid with two paternal chromosomes and one maternal chromosome. The incidence of gestational trophoblastic neoplasia differs substantially between CHM and PHM. However, they are occasionally difficult to diagnose. In this review, auxiliary and experimental methods based on cytogenetic features and advanced molecular detection techniques applied to the diagnosis and analysis of hydatidiform moles are summarized, including basic principles, characteristics, and clinical implications. Short tandem repeat polymorphism analysis is considered the gold standard for the genetic diagnosis of hydatidiform moles. In clinical settings, immunohistochemical analyses of p57KIP2 , an imprinted gene product, are widely used to differentiate CHMs from other conceptuses, including PHMs. Recently, new molecular genetic techniques, such as single nucleotide polymorphism arrays, have been applied to research on hydatidiform moles. In addition to insights from classical methods, such as chromosome analysis, recently developed approaches have yielded novel findings related to the mechanism underlying the development of androgenetic CHMs.

Short tandem repeat polymorphism analysis for primary peritoneal choriocarcinoma: A case report and literature review.

The peritoneum is an extremely rare site for primary choriocarcinoma development. Primary peritoneal choriocarcinoma could be either gestational or nongestational, whereas it is straightforward to ascribe uterine or tubal choriocarcinoma to the gestational origin. Herein, we report a case of primary peritoneal choriocarcinoma that is genetically diagnosed as a gestational subtype originating from an occult complete hydatidiform mole. A 46-year-old female patient with two-time induced abortion histories underwent emergency laparotomy under clinical suspicion of ruptured tubal pregnancy. Laparotomy revealed a hemorrhagic tumor in the left mesosalpinx with apparently intact left ovary and fallopian tube. The excised tumor was pathologically diagnosed as choriocarcinoma. Multiplex short tandem repeat polymorphism analysis revealed an androgenetic/homozygous genotype tumor, identifying its origin as a complete hydatidiform mole. Our literature review of nine primary peritoneal choriocarcinoma cases, including ours, highlighted the importance of tumor genotyping in differentiating between gestational and non-gestational subtypes and identifying the causative pregnancy.

Genetic screening of Chinese patients with hydatidiform mole by whole-exome sequencing and comprehensive analysis.

PURPOSE: We aim to explore if there are any other candidate genetic variants in patients with a history of at least one hydatidiform mole (HM) besides the well-known variants in NLRP7 and KHDC3L. METHODS: The diagnosis of HM type was based on histopathology, and available HM tissues were collected for short tandem repeat (STR) genotyping to verify the diagnosis. DNA extracted from blood samples or decidual tissues of the 78 patients was subjected to whole-exome sequencing (WES). RESULTS: We identified five novel variants in NLRP7, two novel variants in KHDC3L, and a chromosome abnormality covering the KHDC3L locus among patients with HM. We found that patients with HM who carried heterozygous variants in KHDC3L had a chance of normal pregnancy. We also detected four novel genetic variants in candidate genes that may be associated with HM. CONCLUSION: Our study enriched the spectrum of variants in NLRP7 and KHDC3L in Chinese HM patients and provided a new outlook on the effects of heterozygous variants in KHDC3L. The novel candidate genetic variants associated with HMs reported in this study will also contribute to further research on HMs.

Detection of Parental Contribution to Molar Genome Leads to Diagnosis of Recurrent Hydatidiform Mole in a Family with NLRP7 Variants.

Introduction: Genetically, complete hydatidiform mole (CHM) is androgenetic diploid, containing two sets of paternal chromosomes. In most cases, recurrent HM (RHM) is CHM but has diploid biparental chromosome constitution. Case report: We report a mother with RHM, both with biparental diploidy. The mother was compound heterozygous for two variants, c.1720dup, p.(C574Lfs*4) and c.2165A > G, p.(D722G) of the NLRP7 gene, as was a brother who fathered 2 normal pregnancies. Conclusion: The genotype study should be obtained for patients of CHM, even in their first pregnancy, followed by genetic screening for maternal-effect variants in those with biparental moles. This strategy will identify patients in their first pregnancy with HM that have a decreased chance for a normal pregnancy, to allow genetic counseling, perhaps utilizing a donor egg.

Quadruplet Pregnancy with Complete Mole and Three Viable Fetuses.

Background: The coexistence of a hydatidiform mole and a fetus can occur in a multiple pregnancy, being less frequent in triplets and quadruplets because of their infrequency. With assisted reproduction, multiple pregnancies are becoming more frequent, and we can expect more frequent coexistence with a molar pregnancy. Case report: This G3, P1 30-year-old mother, after assisted conception, was diagnosed with a quadruplet pregnancy, one of which was a molar conceptus. Due to the potential for malignancy, the pregnancy was electively terminated. Conclusion: Despite the difficulty in conceiving, elective termination of a multiple pregnancy associated with a molar pregnancy may be the most judicious course of action to protect the mother's life.

A Rare Case of Large Hydatidiform Mole Mimicking a Term Pregnancy.

Molar pregnancy is a type of abnormal pregnancy that usually presents with amenorrhea, vaginal bleeding and elevated serum ß-hCG levels. We report a rare case of complete hydatidiform mole occurring in a 46-year-old P2L2 lady who presented with a term size uterus and elevated serum ß-hCG level (> 15,00,000 per deciliter, anemia (hemoglobin: 8.1 g/dL), difficulty in breathing and minimal vaginal bleeding. During the course of her evaluation, she had profuse vaginal bleeding, she underwent suction and evacuation, but bleeding was not controlled despite measures to control it. She was given uterotonics and antifibrinolytic agents and uterine artery ligation. But was proceeded with emergency hysterectomy for uncontrolled hemorrhage. The content of suction and evacuation was vesicles with blood clots and histopathology was reported as complete hydatidiform mole. The patient received a total of 4 units of packed red blood cells. She was discharged from hospital on 5th postoperative day and was followed up serial serum ß-hCG level. Therefore, complete mole can present with enlarged uterus, vaginal bleeding and anemia. It is also important to note that intractable bleeding following suction and evacuation not being controlled with uterotonics and antifibrinolytic agents and uterine artery ligation may require hysterectomy to save the patient's life.

Refined diagnosis of hydatidiform moles with p57 immunohistochemistry and molecular genotyping: updated analysis of a prospective series of 2217 cases.

Immunohistochemical analysis of p57 expression and molecular genotyping accurately subclassify molar specimens into complete hydatidiform mole (CHM) and partial hydatidiform mole (PHM) and distinguish these from nonmolar specimens. Characteristics of a prospective series of potentially molar specimens analyzed in a large gynecologic pathology practice are summarized. Of 2217 cases (2160 uterine, 57 ectopic), 2080 (94%) were successfully classified: 571 CHMs (570 uterine, 1 ectopic), 498 PHMs (497 uterine, 1 ectopic), 900 nonmolar (including 147 trisomies, 19 digynic triploids, and 4 donor egg conceptions), and 56 androgenetic/biparental mosaics; 137 were complex or unsatisfactory and not definitively classified. CHMs dominated in patients aged < 21 and >45 years and were the only kind of molar conception found in the latter group. Of 564 successfully immunostained CHMs, 563 (99.8%) were p57-negative (1 p57-positive [retained maternal chromosome 11] androgenetic by genotyping). Of 153 genotyped CHMs, 148 (96.7%) were androgenetic (85% monospermic) and 5 were biparental, the latter likely familial biparental hydatidiform moles. Of 486 successfully immunostained PHMs, 481 (99%) were p57-positive (3 p57-negative [loss of maternal chromosome 11], 2 unknown mechanism). Of 497 genotyped PHMs, 484 (97%) were diandric triploid (99% dispermic) and 13 were triandric tetraploid (all at least dispermic). Of 56 androgenetic/biparental mosaics, 37 had a p57-negative complete molar component (16 confirmed as androgenetic by genotyping). p57 expression is highly correlated with genotyping, serving as a reliable marker for CHMs, and identifies molar components and androgenetic cell lines in mosaic conceptions. Correlation of morphology, p57 expression, genotyping data, and history are required to recognize familial biparental hydatidiform moles and donor egg conceptions, as the former can be misclassified as nonmolar and the latter can be misclassified as dispermic CHM on the basis of isolated genotyping results.

Triploid pregnancy-Clinical implications.

Triploidy is a life-limiting genetic aberration resulting from an extra haploid set of chromosomes of paternal (diandric triploidy) or maternal origin (digynic triploidy). Triploidy affects around 1%-2% of all conceptions. The majority of cases is miscarried at early developmental stages. In consequence of genomic imprinting, parental origin affects the phenotype of triploid pregnancies as well as the prevalence and spectrum of related maternal complications. Distinctive ultrasound features of both triploid phenotypes as well as characteristic patterns of biochemical markers may be useful in diagnosis. Molecular confirmation of the parental origin allows to predict the risk of complications, such as gestational trophoblastic neoplasia, hyperthyroidism, hypertension, or preeclampsia associated with the paternal origin of triploidy. Diagnosis of partial hydatidiform mole associated with diandric triploidy is challenging especially in the first trimester pregnancy loss due to the limitations of both histopathology and ultrasound. We present important clinical aspects of triploid pregnancies and indicate unresolved issues demanding further studies.

A possible association between hydatidiform mole and the COVID-19 pandemic: A retrospective cohort study.

OBJECTIVE: To confirm an increase in the number of women with molar pregnancy during the COVID-19 pandemic. METHODS: In this retrospective cohort study, all patients with complete or partial mole diagnosed at our institution between January 1, 2010 and October 31, 2020, were included. To verify whether there was an increase in the incidence of hydatidiform mole (HM) and deliveries in 2020, the incidences for each year from January 2010 to October 2020 were recorded. In addition, we identified all women who were diagnosed with HM from January to October 2020, and compared them with a control group who underwent uterine evacuation for missed abortion of a singleton pregnancy during the same period. We also documented the time taken to diagnose missed abortion or molar pregnancy to check if a delay in diagnosis can explain the increase in HM incidence. RESULTS: Between 2016 and 2019, there was a statistically significant increase in the incidence of molar pregnancy. A further increase occurred in 2020 (odds ratio = 2.071). The mean gestational age of the embryo at the time of diagnosis was smaller in the HM group than in the missed abortion group (6.3 ± 1.67-7.4 ± 2.4, one-sided P = 0.034), meaning that it took more time (days) to diagnose molar pregnancy than missed abortion (22.38 ± 10.32 vs. 15.83 ± 7.83 days, P = 0.012). CONCLUSION: There was a significant increase in the incidence of molar pregnancy during the COVID-19 pandemic, possibly because of the delay in receiving medical care. We recommend providing gynecological primary care services during a crisis, such as a pandemic.

Androgenetic/Biparental Mosaic/Chimeric Conceptions With a Molar Component: A Diagnostic and Clinical Challenge.

Hydatidiform moles (HM) are gestational trophoblastic diseases which arise due to an imbalance in genetic material and which are morphologically characterized by enlarged and irregular chorionic villi and trophoblastic hyperplasia, among other features. The morphologic differential diagnosis for HM encompasses a number of entities including androgenetic/biparental mosaic/chimeric (ABMC) conceptions, an interesting duo of lesions with a nonmolar form (placental mesenchymal dysplasia) and a molar form (typically with a complete HM component). ABMC conceptions contain a mixture of 2 cell populations (1 androgenetic and 1 biparental) and arise as a result of mosaicism (mitotic error in a zygote) or chimerism (fusion of 2 zygotes). Because of their unique molecular underpinnings, these rare lesions show a number of findings including the presence of multiple villous populations, discordant p57 immunostaining, and mixed genotypes. ABMC conceptions are important to accurately diagnose as the molar form in particular carries a risk for persistent gestational trophoblastic diseases and thus requires appropriate treatment and follow-up. In this report, we provide detailed characterizations of 2 such cases of ABMC conceptions with a molar component. Both patients (ages 34 and 31) were in the first trimester of pregnancy and had ultrasound findings concerning for HM. Increased comprehension of the pathogenesis and morphology of ABMC conceptions, combined with ancillary techniques including p57 immunohistochemistry, fluorescence in situ hybridization, and molar genotyping, has allowed us to accurately and efficiently identify these lesions. However, a number of pitfalls exist which may lead to misdiagnosis.