Molecular and histological characteristics of early triploid and partial molar pregnancies

Molar pregnancy has the highest incidence of all gestational trophoblastic diseases. This is a heterogeneous group of diseases, composed of precancerous lesions and gestational trophoblastic tumours. The hydatidiform mole is characterised by varying degrees of proliferation of syncytiotrophoblastic and cytotrophoblastic cells and stromal oedema. Based on established morphological and cytogenetic criteria, molar pregnancy is divided into partial and complete. The risk of persistent trophoblastic disease is higher in complete moles compared with partial moles. The aim of this study was to assess the importance of additional molecular methods as a conjunction to the standard histopathological analysis to accurately determine the type and origin of triploidy and to detect partial molar pregnancy. This study examined a total of 24 cases of triploidy. Apart from the detailed histomorphological analysis, a molecular analysis of the placental tissue and maternal DNA was also performed. Digynic triploidy was found in 15 cases, whereas diandric triploidy was found in nine of the cases. The results showed that due to the histomorphological overlap between partial molar pregnancy and hydropic abortions, concomitant histopathological analysis of the placental tissue and molecular analysis of the placental and maternal DNA can lead to correct diagnosis

Detection of placental chromosomal aberrations in early spontaneous abortions in correlation with the histologic findings

Using a variety of molecular techniques, it has been established that loss of pregnancy occurs in one to two thirds of all fertilized embryosin the first trimester. In about 50% of the cases, chromosomal abnormalities are the cause of early spontaneous abortion. Several histological characteristicsof the placenta, such as presence of villous stromal cavitations, fetal erythro-cytes, umbilical cord, fetal tissue,etc. are suggested as predictive factors for aneuploidy.Two hundred and thirty one cases were analyzed in this prospective study, 50 cases were control artificial abortionsand 181 cases were early spontaneous abor-tionsanalyzed in the period from May 2012 to De-cember 2014. Standard histopathological analysis and molecular techniques based on polymerase chain reaction were usedto analyze the samples.Usingmolecular techniques, aneuploidy was detected in 53.1% of the samples. The most frequently detected aneuploidy was trisomy 16, followed by trisomy 22, 21, 14 and 18. The molecular analysis also enabled dis-tinctionof maternal and paternal origin of the alleles.In the histopathological sample analysis, binary logis-tic regression analysis indicated the presence of trophob-lasticproliferation (p=0.008) and the absence of fetal red bloodcells (p=0.001) as independent significant fac-tors in the prediction of aneuploidy in early sponta-neous abortion.In conclusion, our results show that clinically relevant andaccurate diagnosis of early spontaneous abortionwhich candetermine its causecan only be achieved bya controlled process of selection of the material,histo-pathological and molecular analysis, followed bya necessary correlation of these results

Molecular and Immunohistochemical Characteristics of Complete Hydatidiform Moles

Molar pregnancy is a gestational trophoblastic disease that belongs to the category of precancerous lesions. On the other end of the spectrum are gestational trophoblastic neoplasms such as invasive mole, choriocarcinoma, placental site trophoblastic tumor and epithelioid trophoblastic tumor, which are considered malignant tumors. Based on defined histopathological criteria, molar pregnancy is divided into partial and complete hydatidiform mole. Especially in the case of early complete mole, the diagnosis can be quite challenging and often necessitates additional molecular or immunohistochemical methods. The aim of this study was to assess the importance of additional molecular and immunohistochemical methods to accurately diagnose complete hydatidiform mole and to stress the importance of correct diagnosis and close follow-up of these patients. A total of 367 consecutive cases of spontaneous abortion were analyzed in a 3-year period. Eight cases with histopathological diagnosis of complete molar pregnancy were selected for further analysis. Apart from standard microscopic analysis, additional molecular and immunohistochemical analyses were performed in all eight cases. Most of the histopathological characteristics of complete molar pregnancy were present in all cases, together with complete absence of positivity for the p57 immunohistochemical marker in the cytotrophoblasts and villous stromal cells. The molecular analysis revealed androgenetic diploidy in seven cases and biparental diploidy in one case with more than three consecutive complete molar pregnancies. Additional immunohistochemical and molecular methods can considerably aid in the correct diagnosis of molar pregnancy