The role of deoxyribonucleic acid image cytometric and interphase cytogenetic analyses in the differential diagnosis, prognosis, and clinical follow-up of hydatidiform moles. A report from the Central Molar Registration in The Netherlands

The added value of hysterectomy in the management of gestational trophoblastic neoplasia

BACKGROUND

Despite the undoubted effectiveness of chemotherapeutic treatment in gestational trophoblastic neoplasia (GTN), problems related to toxicity of chemotherapy and chemo-resistant disease have led to reconsideration of the use of hysterectomy. Aim of the present study was to evaluate indications for and outcome of hysterectomy in patients with GTN in a nation-wide cohort.

METHODS

Between 1977 and 2012, we identified all patients diagnosed with GTN and treated with hysterectomy from the Dutch national databases. Demographics, clinical characteristics and follow-up were recorded retrospectively.

RESULTS

One hundred and nine patients (16.5% of all registered patients with GTN) underwent hysterectomy as part of their management for GTN. The majority of patients was classified as low-risk disease (74.3%), post-molar GTN (73.5%) and disease confined to the uterus (65.1%). After hysterectomy, complete remission was achieved in 66.2% of patients with localized disease and in 15.8% of patients with metastatic disease. For patients with localized disease, treated with primary hysterectomy, treatment duration was significantly shorter (mean 3.2weeks and 8.0weeks respectively, p=0.01) with lower number of administered chemotherapy cycles (mean 1.5 and 5.8 respectively, p<0.01) than patients in a matched control group.

CONCLUSION

In selected cases, a hysterectomy may be an effective means to either reduce or eliminate tumor bulk. Primary hysterectomy should mainly be considered in older patients with localized disease and no desire to preserve fertility, whereas patients with chemotherapy-resistant disease may benefit from additional hysterectomy, especially when disease is localized. For patients with widespread metastatic disease, the benefit of hysterectomy lies in the removal of chemotherapy-resistant tumor bulk with subsequent effect on survival.

A Molar Pregnancy within the Fallopian Tube

Background. Discussion of the incidence of molar pregnancy and ectopic pregnancy. Role of salpingostomy and special considerations for postoperative care. Case. The patient is a 29-year-old G7P4 who presented with vaginal bleeding in the first trimester and was initially thought to have a spontaneous abortion. Ultrasound was performed due to ongoing symptoms and an adnexal mass was noted. She underwent uncomplicated salpingostomy and was later found to have a partial molar ectopic pregnancy. Conclusion. This case illustrates the rare occurrence of a molar ectopic pregnancy. There was no indication of molar pregnancy preoperatively and this case highlights the importance of submitting and reviewing pathological specimens.

Morphological, immunohistochemical and chromosome in situ hybridization in the differential diagnosis of Hydatidiform Mole and Hydropic Abortion

OBJECTIVE

To explore the utility of histological, immunohistochemical and chromosome in situ hybridization (CISH) test in the differential diagnosis of Complete Hydatidiform Mole (CHM), Partial Hydatidiform Mole (PHM) and Hydropic Abortion (HA).

STUDY DESIGN

We analyzed the histological characteristics, p57kip2 and Factor VIII expression and CISH test in 38 cases with some diagnostic concerns, comprising 13 CHM, 14 PHM and 11 HA.

RESULTS

Our results indicate that p57kip2 expression and the ploidy assessed by CISH were essential for the reclassification of 2 cases, one from CHM to PHM and another from PHM to HA, as well as for confirming the previous diagnosis in cases where there were conflicting features. p57kip2 expression is diagnostic if no cells at all present it (CHM) or when there are over 10% of cells expressing it (PHM and HA).

CONCLUSIONS

We concluded that there is no single criterion for the distinction of CHM, PHM and HA. So p57kip2 expression and CISH test can be used in association with the histological findings for the differential diagnosis of the three conditions in cases presenting some concern for definitive diagnosis.

Vasculogenesis in complete and partial hydatidiform mole pregnancies studied with CD34 immunohistochemistry

BACKGROUND

Defective chorionic villous vascularization is present in pregnancies complicated by absent or abnormal embryonic development. The aim of this study was to investigate the embryonic and/or maternal genomic influence on vasculogenesis in diploid complete hydatidiform mole (CHM) and in triploid partial hydatidiform mole (PHM) in comparison with normal development.

METHODS

Mean villous stromal area and functional vascular area, vessels with a lumen and haemangiogenetic cords, peripherally or centrally located were measured and counted in chorionic villi of 12 CHM, 12 normal pregnancies (termination of pregnancy, TOP) and 15 PHM of which nine were without an embryo (PHM-E) and six were with an embryo (PHM + E), using quantitative CD34 immunohistochemistry.

RESULTS

TOP showed significantly more vessels per chorionic villus, centrally and peripherally located (median, range), than CHM, PHM-E and PHM + E (4.0, 0-9 versus 0.0, 0-11, 0.0, 0-18 and 1.0, 0-21). CHM showed significantly more centrally located cords than PHM-E, PHM + E and TOP (1.5, 0-22 versus 1.0, 0-15, 0.5, 0-8 and 1.0, 0-2).

CONCLUSIONS

Initiation of chorionic villous vasculogenesis is independent of the maternal genome (CHM). The development of an embryo, however, is obligatory for the modulation of normal vascularization resulting in a well developed vasculosyncytial membrane.

Determination of DNA ploidy by fluorescence in situ hybridization (FISH) in hydatidiform moles: Evaluation of FISH on isolated nuclei

In the past 20 years, the diagnosis of hydatidiform moles has become more difficult because of the widespread use of early uterine evacuation. Differentiating hydropic degeneration, partial, and complete moles is important because of their different prognosis. However, clinical diagnosis is less obvious, and the pathologist has to separate the different entities on the basis of very subtle morphologic criteria. In difficult cases, ploidy may be determined by various methods, including fluorescence in situ hybridization (FISH) on routine histological sections from paraffin-embedded specimens. However, FISH analysis is often difficult because of the presence of numerous truncated nuclei. In this context, we have tested the advantages of FISH on isolated nuclei, a well-known variant of the technique that might be more sensitive. We reviewed 24 cases of products of abortion: hydropic degenerations, complete hydatidiform moles, partial moles, and nonmolar triploidies. After histological review, FISH on isolated nuclei proved conclusive in all cases. The results could be easily interpreted thanks to the reduced number of truncated nuclei. The percentage of cells with 2 signals was always >70% in the diploid cases and >60% in the triploid cases. In conclusion, this sensitive technique seems to be a valuable tool for the diagnosis of moles.

Metastatic trophoblastic disease after an initial diagnosis of partial hydatidiform mole: genotyping and chromosome in situ hybridization analysis

BACKGROUND

Hydatidiform mole (HM) is classified into partial (PHM) and complete (CHM) subtypes according to histopathologic and genetic criteria. Traditionally, it is believed that PHM carries a better prognosis and rarely develops metastasis. However, making a distinction between PHM and CHM using histologic criteria alone may be difficult.

METHODS

The authors used fluorescent microsatellite genotyping following laser-capture microdissection and chromosome in situ hybridization (CISH) to perform a genetic analysis of six patients with histologically diagnosed PHM who subsequently developed metastatic gestational trophoblastic neoplasia.

RESULTS

Patients ranged in age from 25 years to 44 years (mean, 33.2 years). The gestational age of the molar pregnancies varied from 6 weeks to 20 weeks. All six patients had pulmonary metastases, with additional liver metastasis in two patients. Among the six patients with histologically diagnosed PHM, it was found that four patients had a diploid karyotype and no maternal alleles; thus, their neoplasms actually were CHM. Maternal genome was detected in the remaining two patients consistent with a biparental origin, and these patients had a triploid karyotype. CISH findings in all patients correlated with the genotyping findings. Triploid HM had maternally derived alleles, whereas diploid HMs were purely androgenetic.

CONCLUSIONS

In the current study, which may be the largest series of genetically analyzed metastatic PHMs to date, the difficulty of histologic distinction between PHM and CHM was confirmed. Molecular analysis may help to refine the classification of HM. Although the current findings support the belief that most aggressive trophoblastic diseases are derived from CHM, a small number of PHMs do progress to metastatic disease. Thus, the current study reaffirmed that all patients with HM should be followed closely irrespective of histologic subclassification.

Analysis of gestational trophoblastic disease by genotyping and chromosome in situ hybridization

Hydatidiform mole is classified into partial and complete subtypes according to histopathological and genetic criteria. Distinction between the two by histology alone may be difficult. Genetically, a complete mole is diploid without maternal contribution, whereas a partial mole is triploid with a maternal chromosome complement. To assess the accuracy of histological diagnosis by correlating with the genetic composition, we performed fluorescent microsatellite genotyping to detect the presence or absence of maternal genome in a hydatidiform mole and carried out chromosome in situ hybridization to analyze the ploidy. For genotyping analysis, paraffin sections of 36 complete and nine partial moles, diagnosed according to histological criteria, were microdissected and DNA was separately extracted from the decidua and molar villi. Six pairs of primers that flank polymorphic microsatellite repeat sequences on five different chromosomes were used. In all, 34 cases, including 31 complete moles and three partial moles diagnosed histologically, showed no maternal contribution by genotyping; thus these could be genetically considered as complete mole. The other 11 cases (five complete moles and six partial moles previously diagnosed by histology) showed the presence of maternal contribution and were genetically diagnosed as partial moles. The genotyping results correlated with histological evaluation in 88% (37/45) of hydatidiform mole and correlated with chromosome in situ hybridization findings in all the cases, that is, triploid hydatidiform moles had maternal-derived alleles, while diploid hydatidiform moles were purely androgenetic. Compared with genetic diagnosis, histological evaluation was more reliable for the diagnosis of a complete mole (91%, 31/34) than that of a partial mole (55%, 6/11) (P=0.0033). Seven complete moles and three partial moles diagnosed genetically developed gestational trophoblastic neoplasia. To conclude, genotyping and chromosome in situ hybridization can provide reliable adjunct to histology for the classification of a hydatidiform mole, especially in cases with difficult histological evaluation and early gestational age. As a partial mole still carries a risk of developing gestational trophoblastic neoplasia, follow-up is considered necessary for both complete and partial moles.

Cytokeratin 20 as a biomarker of gestational trophoblastic disease: diagnostic and prognostic significance

OBJECTIVES

This study was designed to examine whether cytokeratin 20 (CK20) is expressed in molar pregnancies and may therefore be used in the diagnosis of gestational trophoblastic disease (GTD). The potential of CK20 expression in predicting the evolution and the prognosis of the different subtypes of GTD was also assessed.

METHODS

A total of 48 samples were studied for CK20 expression by RT-PCR methodology. Among these, 24 samples were obtained by curettage of the uterine cavity of patients diagnosed with hydatidiform mole (14 complete moles and 10 partial moles), 4 samples were obtained from choriocarcinoma cell lines (2 JAR and 2 JEG), and 20 samples were of normal trophoblast (control group) obtained from patients that underwent elective termination of pregnancy.

RESULTS

Expression of CK20 was identified in all the samples of complete mole (CM), all choriocarcinoma cell lines, and 50% of the patients with partial mole (PM). None of the preparations of normal trophoblastic tissue from the control group expressed the CK20. A significant difference (P < 0.00001) was found in CK20 expression between samples of patients with GTD and control samples. Comparison between CK20 expression in CMs and PMs revealed a significantly more frequent expression of CK20 in CMs (P = 0.006). More than 50% of the patients with PMs that were positive for CK20 had an invasive evolution.

CONCLUSIONS

In our opinion, CK20 may assist in distinguishing between molar and normal trophoblastic tissue and may be considered a marker of GTD. In cases in which pathological classification of different subtypes of GTD is in doubt, CK20-positive expression is suggestive for a CM whereas CK20-negative is more indicative for PM.

A large yolk sac may be important in the early diagnosis of gestational trophoblastic disease: a case report

A large yolk sac in a deformed shape gestational sac was detected by ultrasonography in an 8 week pregnant woman. The disappearance of the yolk sac and the gestational sac, enlargement of the uterine cavity and a heterogeneous appearance similar to early gestational trophoblastic disease were recognized when ultrasonographic examination was performed 2 weeks later. After uterine evacuation, partial hydatidiform mole was diagnosed by histopathological evaluation of the curettage material. In our study, the role of the large yolk sac in predicting trophoblastic disease is discussed.

Amniotic tissue in complete hydatidiform moles can be androgenetic

The purpose of this study was to determine whether amniotic tissue found associated with cases of complete hydatidiform mole (CM) was genetically identical to the CM, and therefore part of the molar pregnancy, or genetically dissimilar to the CM, suggesting derivation from a twin pregnancy. DNA was prepared from formalin-fixed, paraffin-embedded blocks of tissue containing both CM and amnion. Maternal DNA was prepared from decidual tissue in the same blocks, or from a maternal blood sample. Fluorescent microsatellite genotyping was carried out to determine the origin of both the CM and the amniotic tissue. In one of six cases examined, the amniotic tissue was genetically different from the CM and was therefore likely to be derived from a twin pregnancy. In the five remaining cases, the amniotic tissue was genetically identical to the CM and was likely to be derived from the same conceptus. It is concluded that androgenetic CM can support the development of amniotic tissue and that some early embryonic development may occur in CM. The presence of amnion, or other fetal tissues, associated with molar tissue should not therefore always be considered indicative of a diagnosis of partial mole (PM).