Non-molar Abortions Research Articles

Microsatellite DNA Genotyping and Flow Cytometry Ploidy Analyses of Formalin-fixed Paraffin-embedded Hydatidiform Molar Tissues

Hydatidiform mole (HM) is an abnormal human pregnancy characterized by excessive trophoblastic proliferation and abnormal embryonic development. There are two types of HM based on microscopic morphological evaluation, complete HM (CHM) and partial HM (PHM). These can be further subdivided based on the parental contribution to the molar genomes. Such characterization of HM, by morphology and genotype analyses, is crucial for patient management and for the fundamental understanding of this intriguing pathology. It is well documented that morphological analysis of HM is subject to wide interobserver variability and is not sufficient on its own to accurately classify HM into CHM and PHM and distinguish them from hydropic non-molar abortions. Genotyping analysis is mostly performed on DNA and tissues from formalin-fixed paraffin-embedded (FFPE) products of conception, which have less than optimal quality and may consequently lead to wrong conclusions. In this article, detailed protocols for multiplex genotyping and flow cytometry analyses of FFPE molar tissues are provided, along with the interpretation of the results of these methods, their troubleshooting, and integration with the morphological evaluation, p57KIP2 immunohistochemistry, and fluorescence in situ hybridization (FISH) to reach a correct and robust diagnosis. Here, the authors share the methods and lessons learned in the past 10 years from the analysis of approximately 400 products of conception.

Histomorphological Study of Gestational Trophoblastic Lesions in a Tertiary Medical Centre: A Prospective Study

Background: Gestational trophoblastic diseases(GTDs) consists of pregnancy related disorders ranging from benign Hydatidiform mole, Invasive mole to neoplastic conditions including Choriocarcinoma, Placental site trophoblastic tumor and Epitheloid trophoblastic tumor with varying potential for local invasion and metastasis. GTDs mimic growth pattern encountered in early normal placental development, nonmolar abortions and variety of nontrophoblastic lesions. Therefore an appreciation of different types of GTDs with its histomorphological manifestations are important for the confirmation of diagnosis. Thus the study was undertaken. Materials & methods: The material for the study comprised of products of conception specimens received in the Department of Pathology, J.J.M. Medical college, Davangere, India during the period of 2 years. Detailed gross examination was done before fixation and subsequent microscopic analysis was done. Results: 65 cases of GTDs were diagnosed in 495 cases of products of conception. 37 cases of complete mole, 27 cases of partial mole and one case of Invasive mole were diagnosed. Diffuse hydropic swelling of the villi, round smooth villous outline, circumferential trophoblastic proliferation and focal hydropic swelling of the villi, irregular scalloping outline of the enlarged villi, focal trophoblastic cell proliferation were characteristic features of complete & partial mole respectively. Histomorphological features were analysed in all the cases and compared with studies done by others. Conclusion: The classification and histomorphological analysis of GTDs are important elements for better understanding of the disease. Studies are needed to look for ancillary markers in distinguishing different types of GTDs and for predicting the prognosis. DOI: 10.21276/APALM.1193

Gestational Trophoblastic Disease: Clinical and Imaging Features.

Gestational trophoblastic disease (GTD) is a spectrum of both benign and malignant gestational tumors, including hydatidiform mole (complete and partial), invasive mole, choriocarcinoma, placental site trophoblastic tumor, and epithelioid trophoblastic tumor. The latter four entities are referred to as gestational trophoblastic neoplasia (GTN). These conditions are aggressive with a propensity to widely metastasize. GTN can result in significant morbidity and mortality if left untreated. Early diagnosis of GTD is essential for prompt and successful management while preserving fertility. Initial diagnosis of GTD is based on a multifactorial approach consisting of clinical features, serial quantitative human chorionic gonadotropin (β-hCG) titers, and imaging findings. Ultrasonography (US) is the modality of choice for initial diagnosis of complete hydatidiform mole and can provide an invaluable means of local surveillance after treatment. The performance of US in diagnosing all molar pregnancies is surprisingly poor, predominantly due to the difficulty in differentiating partial hydatidiform mole from nonmolar abortion and retained products of conception. While GTN after a molar pregnancy is usually diagnosed with serial β-hCG titers, imaging plays an important role in evaluation of local extent of disease and systemic surveillance. Imaging also plays a crucial role in detection and management of complications, such as uterine and pulmonary arteriovenous fistulas. Familiarity with the pathogenesis, classification, imaging features, and treatment of these tumors can aid in radiologic diagnosis and guide appropriate management. ©RSNA, 2017.

Flow Cytometric DNA Analysis and Histopathologic Re-Evaluation of Paraffin Embedded Samples from Hydatidiform Moles and Hydropic Abortions.

Distinction of hydatidiform moles (HMs) from non-molar abortions and sub-classification of HMs are important for clinical practice; yet, diagnosis based solely on morphology is affected by interobserver variability. The objective of this study was to determine the role of DNA flow cytometry in distinguishing molar from non-molar pregnancies. This retrospective study was conducted at the Department of Pathology, Women's Hospital, Tehran University of Medical Sciences, Tehran, Iran, between 2006 and 2010. DNA ploidy analysis and histopathologic re-evaluation were performed on paraffin-embedded tissue from 36 (17 complete and 19 partial) molar and 24 hydropic abortus (HA) cases which were previously diagnosed based on histomorphologic study. Of the 17 cases initially diagnosed as complete HM (CHM), 9 were diploid, 2 were triploid, 5 were tetraploid and 1 was aneuploid. Of the 19 initial partial HMs (PHMs), 2, 8, 1 and 8 cases were diploid, triploid, tetraploid and aneuploid, respectively. In the initial HA category (n=24), 14 diploid, 1 triploid, 5 tetraploid, and 4 aneuploid cases existed. Following flow cytometry and histopathologic reevaluation, 1 case with previous diagnosis of HA was reclassified as PHM, 2 initial PHMs were reclassified as CHM and 2 initial CHMs were categorized as PHM. The results show that correct diagnosis of PMH is the main challenge in histological diagnosis of gestational trophoblastic disease (GTD). DNA flow cytometric analysis could be an informative supplement to the histological interpretation of molar and hydropic placentas.

Specific expression patterns of epithelial to mesenchymal transition factors in gestational molar disease

IntroductionThe epithelial to mesenchymal transition, a well-known and re-emerging model in pathology, has not been completely investigated in the field of gestational pathology. This study aims at improving the comprehension of this process in molar disease, even looking for new possible immunohistochemical markers. Materials and methodsWe have analysed the immunohistochemical expression of Twist1 and Snai2, two of the most important transcription factors involved in epithelial to mesenchymal transition, in formalin-fixed paraffin-embedded samples of 23 spontaneous abortive pregnancies, 22 molar pregnancies (10 partial and 12 complete) and 7 term placentas. ResultsTwist1 and Snai2 were highly expressed in stromal villi cells of molar disease. Particularly, Twist1 was highly expressed in complete moles compared to both abortive pregnancies (p < 0.001) and partial moles (p < 0.05). Also Snai2 was more expressed by complete moles, differentiating them from non-molar abortions (p < 0.05). DiscussionOn the basis of the known cadherins and claudins expression in these pathologies, our new findings reinforce the hypothesis of the involvement of epithelial to mesenchymal transition in early molar pregnancies and above all in complete moles. Furthermore, we highlighted that in molar disease not only the trophoblast, but even the villi stromal cells, are involved. Thanks to their specificity, furthermore, these Twist1 and Snai2 could be used as additional immunohistochemical tool in the diagnosis of complete molar disease, with Twist1 as the first choice.

Clinical Features of Early-Stage Nonhydropic Mole for Diagnosis of Persistent Trophoblastic Disease

To characterize the clinical features of "nonhydropic" hydatidiform mole and to investigate regression of serum human chorionic gonadotropin (hCG) as an aid in detecting persistent trophoblastic disease after nonhydropic hydatidiform mole. Our study included women with histologically diagnosed nonhydropic molar pregnancies. Women did not exhibit macroscopic or characteristic ultrasonographic appearances specific to hydatidiform mole. Regression of serum hCG levels was compared with abortions of nonmolar pregnancies, which were histologically confirmed. Among 34 nonhydropic molar pregnancies, 32 complete hydatidiform moles were analyzed, excluding two partial hydatidiform moles. Compared with nonmolar aborted pregnancies, pre-evacuation hCG levels were significantly higher in the 32 complete hydatidiform moles. The 32 molar pregnancies progressed to 24 cases of spontaneous remission and eight cases of persistent trophoblastic disease. Among patients with spontaneous remission, the time at which serum hCG levels became undetectable and the onset of first postabortion menstruation were similar to those in patients who had nonmolar abortions. In all patients who experienced regression, serum hCG was undetectable after the third postabortion menstruation. In all patients with persistent trophoblastic disease, serum hCG levels exceeded 25 milli-international units/mL 4 weeks after evacuation. Without histological confirmation, it is difficult to diagnose nonhydropic molar pregnancy based solely on clinical presentation. Follow-up studies of serum hCG levels 4 weeks after abortion and after the third postabortion menstruation may aid in detecting impending persistent trophoblastic disease. II.

Diagnosis of Hydatidiform Moles by Polymorphic Deletion Probe Fluorescence in Situ Hybridization

Because products of conception often contain maternal and villous tissues, the determination of maternal and villous genotypes based on genetic polymorphisms can help discern maternal and paternal chromosomal contribution and aid in the diagnosis of hydatidiform moles. Polymorphic deletion probe (PDP) fluorescence in situ hybridization (FISH) probes based on copy number variants are highly polymorphic and allow in situ determination of genetic identity. By using three informative PDPs on chromosomes 2p, 4q, and 8p, we compared maternal with villous genotypes and determined the ploidy of villous tissue. PDP FISH was performed on 13 complete moles, 13 partial moles, 13 nonmolar abortions, and an equivocal hydropic abortion. PDP FISH permitted definitive diagnosis of complete moles in five of 13 cases for which maternal and villous genotypes were mutually exclusive. A complete mole was highly suspected when all three PDP loci showed homozygous villous genotypes. The diagnosis of a complete mole by PDP FISH yielded a theoretical test sensitivity of 87.5%, specificity of 91.8%, an observed test sensitivity of 100%, and specificity of 92.3%. Triploidy was observed in all partial moles, in which diandric triploidy was confirmed in six cases. In the equivocal hydropic abortion, PDP FISH combined with p57 immunofluorescence revealed placental androgenetic/biparental mosaicism. PDP FISH can be used in clinical practice and research studies to subclassify hydatidiform moles and evaluate unusual products of conception.

Assessment of the role of histopathology and DNA image analysis in the diagnosis of molar and non-molar abortion: A study of 89 cases in the center of Tunisia

This study retrospectively evaluated the histopathological criteria commonly used in the literature on the diagnosis of hydatidiform mole, in correlation with the diagnosis rendered previously. The molar and non-molar cases seen in the first-trimester of pregnancy were separately reviewed by two pathologists. The correlation between the consensual histological diagnosis and the ploidy status was then evaluated. We retrospectively studied 89 specimens of abortus conception, including 35 complete hydatidiform moles (CHM), 12 partial hydatidiform moles (PHM), and 42 hydropic abortions (HA). The final histopathological diagnosis was compared with the results of DNA content detected by imaging analyzer (Samba 200), studying all cases of molar pregnancy and 4 cases of HA (initially diagnosed as molar pregnancies). In the consensus histological diagnosis, the cases were reclassified as follows: 30 CHM (initial diagnosis (ID): 27 CHM and 3 PHM), 12 PHM (ID: 6 PHM and 6 CHM), and one case with a persistent problem in differentiating PHM from HA and 46 HA (ID: 42 HA, 2 CHM, and 2 PHM). An agreement between the two pathologists was reached in 77 cases ( K=0.72, 0.52, and 0.9, respectively, for CHM, PHM, and HA). The ploidy study demonstrated diploidy in 56.6% (17/30) of CHM and triploidy in 58.3% (7/12) of PHM. In the 4 cases of HA studied, 3 were diploid and 1 case was aneuploid. Our study demonstrated that several histopathological criteria could be used for the distinction between PHM, CHM, and HA. However, the study of DNA cannot be the technique of choice to distinguish between these entities. Some cases remain problematic since the morphological criteria are not easily reproducible. New sensitive techniques might resolve these dilemmas.

Persistent gestational trophoblastic disease is rarely, if ever, derived from non-molar first-trimester miscarriage

Traditional epidemiologic data suggest that persistent gestational trophoblastic disease (pGTD), may follow, and be derived from, either molar pregnancy, non-molar term pregnancy or first-trimester non-molar miscarriage. We examined a database of cases of possible or probable hydatidiform moles and proven pGTD derived from the Regional Trophoblastic Disease Unit, Charing Cross Hospital, London. There were 424 cases (6%), in whom the initial registered diagnosis was that of PHM or CHM but central histopathological review diagnosed a definite non-molar hydropic abortion (HA). In eight of the 424 (2%), although the histology of the most recent index pregnancy was that of non-molar miscarriage, there was a previous history of pregnancy affected by hydatidiform mole; two of these developed subsequent pGTD. Of a further 86 cases referred for a histopathological opinion prior to registration which demonstrated definite non-molar HA, none developed pGTD (zero of 510 (0%, 95% CI 0-0.7%)). During the same period there were 352 cases with pGTD requiring chemotherapy. In 31 cases, the only known pregnancy was the preceding apparent non-molar HA. However, of these, there were only three cases in whom the preceding histological products of conception had been centrally reviewed and were suggestive of non-molar pregnancy. However, in all three of these cases, the specimens were inadequate for definite exclusion of molar pregnancy. In one case in whom no material was available for review, molecular genetic analysis using restriction fragment length polymorphisms was carried out, and the choriocarcinoma was genetically derived from a previous molar pregnancy rather than the preceding HA. There were therefore no cases identified on the database of the trophoblastic disease unit of pGTD requiring treatment in whom the trophoblastic tumour could be genetically proven to have arisen from the preceding first trimester non-molar HA. We suggest that the risk of pGTD developing from a histologically confirmed non-molar HA is less than 1 in 50,000 and that the majority of pGTD cases previously reported to have been caused by a non-molar miscarriage probably represent disease due to an unrecognised early molar pregnancy.

Extravillus Endovascular Implantation Site Trophoblast Invasion is Abnormal in Complete versus Partial Molar Pregnancies

This study examines endovascular trophoblast invasion in pregnancies complicated by complete hydatidiform mole (CM), partial hydatidiform mole (PM) and non-molar abortions (HA). Two hundred consecutive cases from a supra-regional referral centre for suspected trophoblastic disease were examined histologically with particular regard to the presence or absence of endovascular trophoblast invasion of decidual vessels. There were 57CM, 75PM and 68HA. The prevalence of normal endovascular invasion of decidual vessels was significantly lower in CM compared to all other clinical groups, amongst which there were no significant differences. Endovascular trophoblast was identified in about 80 per cent of HA and PM moles, compared to only around 25 per cent of CM (Z=−4.0, P< 0.0001). The majority of cases of complete mole demonstrated a similar appearance, of implantation site showing florid interstitial extravascular trophoblast invasion with surrounding of decidual vessels but without normal endovascular trophoblast invasion or ‘plugging’ seen. In many cases, there also appeared to be destruction of decidual vessels with interstitial haemorrhage and extensive fresh blood clot present in the histological sections. These findings may provide some explanation regarding the mechanism of clinical findings in molar pregnancy.

Presentation and management of choriocarcinoma after nonmolar pregnancy

To ascertain the mode of presentation and treatment outcome for women with choriocarcinoma after a nonmolar pregnancy. Retrospective analysis of case records between 1985 and 1994. A referral centre for trophoblastic disease. One hundred women with choriocarcinoma: 62 after a live birth, six after a live birth preceded by a molar pregnancy and 32 after a nonmolar abortion. Choriocarcinoma after nonmolar pregnancies represent 17% of the total gestational trophoblastic tumours requiring treatment. Vaginal bleeding was the commonest symptom in all groups, but symptoms from metastatic disease were important in the group presenting after a live birth. Metastatic disease was present in 31% of cases after live birth and 43% post-abortion. The median interval between the antecedent pregnancy and choriocarcinoma was five and six months, respectively. High risk multi-agent chemotherapy was required in 82% and 60% of cases, respectively. The mortality rate was significantly higher after a live birth than a nonmolar abortion (21% vs 6%). Treatment of choriocarcinoma after a live birth is associated with an unacceptably high mortality rate. Vaginal bleeding is an important early symptom and a pregnancy test should be performed if it persists after usual medical treatment.

Genetic Origin Analysis of Hydatidiform Mole and Non-Molar Abortion Using the Polymerase Chain Reaction Method

Departments of Obstetrics and Gynecology, and Molecular Biology, School of Medicine, Keio University, Tokyo, Japan. Acta Obstet Gynecol Scand 1994;73:719-725

Genetic origin analysis of hydatidiform mole and non-molar abortion using the polymerase chain reaction method.

The study attempts to determine the genetic origin of hydatidiform mole and non-molar abortion using the polymerase chain reaction (PCR) method, and reevaluates this method as a possible diagnostic tool for hydatidiform mole. A total of 71 cases which consists of 21 complete hydatidiform moles, three partial hydatidiform moles, and 47 non-molar abortions were investigated. The genetic origin was analyzed by the PCR method applied to the variable number of tandem repeat regions of the Apolipoprotein B gene, the human type-II collagen gene, and the probe YNZ22. Chromosomal analysis was also performed. Genetic origin was determined in 58 out of 71 cases (83.1%). All of the complete hydatidiform moles were androgenic, having only paternal alleles. On the other hand, all the partial hydatidiform moles and non-molar abortions revealed clear biparental contribution. Besides triploid partial hydatidiform moles, one non-molar abortion showed two paternal and one maternal complements. Our results were compatible with the classical theory of androgenic origin of complete hydatidiform mole; only complete hydatidiform mole is caused by androgenesis. We also found no complete hydatidiform mole of biparental origin. In conclusion, this PCR method brings a new aspect of genetic origin in the diagnosis of trophoblastic disease. It would be interesting to explore how morphologic subgrouping and genetic origin relate to the prognosis of trophoblastic disease.

Comparison of villous trophoblast proliferation rate in hydatidiform mole and non-molar abortion by assessment of proliferating cell nuclear antigen expression

This study examines the proliferative activity of trophoblast in hydatidiform mole, non-molar hydropic abortion and non-molar spontaneous abortion. Nine cases of complete mole, 10 cases of partial mole, eight cases of non-molar hydropic abortion and six cases of non-hydropic second trimester abortion were examined by routine histopathology and the rate of cell proliferation was assessed by immunoreactivity for proliferating cell nuclear antigen (PCNA). Hydropic abortion showed a significantly lower PCNA index than complete mole and partial mole. There was no significant difference in PCNA index between partial mole and non-hydropic abortion. The trophoblast of partial hydatidiform mole demonstrates significant cell proliferation but this, although higher than that of hydropic abortion, is no higher than that of non-hydropic abortion of a similar gestational age. The role of partial mole as a precursor of persistent gestational trophoblastis disease remains unclear.

Partial hydatidiform mole with subsequent trophoblastic tumor; a case report

A case of partial hydatidiform mole revealed by genetic marker analysis one maternal and two paternal chromosome complements. Levels of serum human chorionic gonadotropin were persistently elevated during follow-up. Avillous curettage specimens prior to chemotherapy were morphologically suspicious for gestational choriocarcinoma. It is still uncertain whether the risk for gestational choriocarcinoma preceded by partial mole exceeds the risk related to non-molar abortions. Careful follow-up with serial serum human chorionic gonadotropin levels is required to detect persistent disease.

Immunohistochemical studies of fetal trophoblast and maternal decidua in hydatidiform mole and choriocarcinoma

The survival of the fetoplacental unit to term in a potentially hostile environment remains an immunological enigma. The development of trophoblast-reactive monocional antibodies (mAbs) has allowed in situ characterization of phenotypically distinct villous and extravillous fetal trophoblast populations in normal human pregnancy (Bulmer and Johnson, 1985). Maternal decidual leucocytes have also been defined by the same approach: macrophages are common throughout gestation, often closely associated with extravillous trophoblast (Bulmer and Johnson, 1984; Smith, Bulmer and Wells, 1986), whereas granulated lymphocytes expressing certain T-cell differentiation antigens are prominent only in early pregnancy tissues (Bulmer and Sunderland, I&; Bulmer, Johnson and Buimer, 1987). The immunobiological importance of both fetal trophoblast surface antigens and the local maternal leucocytic response in successful implantation and placentation are of current interest. The response of gestational choriocarcinoma to chemotherapy has highlighted the interrelationship between this tumour and the maternal host. It is often associated with a local host mononuclear cell response (Elston, 1978) and high serum levels of anti-paternal lymphocytotoxic antibodies (Shaw et al, 1979). In Caucasian populations, approximately equal numbers of cases of choriocarcinoma follow normal term delivery, molar pregnancy and non-molar abortion, although the proportion following hydatidiform mole is higher in Japan (World Health Organization, 1983). The risk of choriocarcinoma following a molar pregnancy is around one thousand times greater than after normal term delivery (Bagshawe et al, 1973). but it is likely that choriocarcinoma ensues in no more than 5 per cent of hydatidiform moles (World Health Organization, 1983). Complete hydatidiform moles are diploid and of androgenetic origin (Kajii and Ohama, 1977) and hence are fully allogeneic with the maternal host. Most are homozygous 46XX and may arise by fertilization of an empty egg by a haploid sperm which dupli-

Human chorionic gonadotropin levels in complete and partial hydatidiform moles and in nonmolar abortuses

The rates of regression of human chorionic gonadotropin (hCG) in patients with complete hydatidiform moles, partial hydatidiform moles, and nonmolar abortions were compared. No difference in rates of regression was found among the three groups, but levels of hCG immediately after uterine evacuation were significantly higher in the group with complete hydatidiform moles. Differences in the time required for hCG levels to become undetectable were attributed to the difference in the degree of initial elevation of hCG.