P53 expression in various types of hydropic placentas (through ploidy analysis as a complementary tool in diagnosis of samples).

BACKGROUND: Placentas characterized by hydropic swelling of chorionic villi occur in a spectrum of pathological conditions including hydropic abortion (HA), partial hydatidiform mole (PHM) and complete hydatidiform mole (CHM). The purpose of this study was to investigate whether the expression of p53 tumour suppressor protein could differentiate these various types of hydropic placentas. METHODS: p53 immunohistochemical staining was performed in 19 molar (8 PHM and 11 CHM) and 10 non-molar (HA) formalin-fixed, paraffin-embedded tissue samples. Ploidy analysis using flow cytometry was performed as a complementary tool in diagnosis of samples. RESULTS: DNA histograms obtained from all samples had confirmed diploidy in HAs and CHMs and triploidy in PHMs. p53 immunoreactivity was assessed in villous cytotrophoblasts, syncytiotrophoblasts and stromal cells. The p53 positive reaction was predominantly observed in the nuclei of cytotrophoblastic cells and rarely in stromal cells, no reaction was seen in syncytiotrophoblasts. The mean percentage of p53 positive cells were 6.10±3.75 for HA, 25.87±13.4 for PHM and 39.83±18.76 for CHM. There was a significant difference in P53 immunoreactivity of cytotrophoblastic cells between CHM and HA (P<0.001), and between PHM and HA (P=0.004). There was no significant difference in immunohistochemical reactivity between CHM and PHM (P=0.068). CONCLUSION: This study confirms that p53 immunostaining may be helpful in distinguishing complete and partial hydatidiform mole from hydropic abortion, but not complete hydatidiform mole from partial hydatidiform mole.

DNA flow cytometric analysis in variable types of hydropic placentas.

BACKGROUND: Differential diagnosis between complete hydatidiform mole, partial hydatidiform mole and hydropic abortion, known as hydropic placentas is still a challenge for pathologists but it is very important for patient management. OBJECTIVE: We analyzed the nuclear DNA content of various types of hydropic placentas by flowcytometry. MATERIALS AND METHODS: DNA ploidy analysis was performed in 20 non-molar (hydropic and non-hydropic spontaneous abortions) and 20 molar (complete and partial moles), formalin-fixed, paraffin-embedded tissue samples by flow cytometry. The criteria for selection were based on the histopathologic diagnosis. RESULTS: Of 10 cases histologically diagnosed as complete hydatiform mole, 9 cases yielded diploid histograms, and 1 case was tetraploid. Of 10 partial hydatidiform moles, 8 were triploid and 2 were diploid. All of 20 cases diagnosed as spontaneous abortions (hydropic and non-hydropic) yielded diploid histograms. CONCLUSION: These findings signify the importance of the combined use of conventional histology and ploidy analysis in the differential diagnosis of complete hydatidiform mole, partial hydatidiform mole and hydropic abortion.

Detection of sugar chain expression in hydatidiform mole using lectin histochemistry.

BACKGROUND: Hydatidiform moles carry a significant risk for developing persistent gestational trophoblastic disease. Lectins are useful tools to identify cellular glycosylation pattern and changes in glycosylation that occur during growth, development, differentiation and also, during disease states. OBJECTIVES: Considering the changes in glycosylation that occur during cell proliferation, differentiation and transformation, the aim of the present study was to evaluate the sugar chain expression in hydatidiform mole by using HRP-conjugated lectins. MATERIALS AND METHODS: Lectin histochemistry with a panel of HRP-conjugated lectins comprising SBA, PNA, VVA, UEA-1, LTA, GS-І (B4) and WGA were performed in 20 molar (partial & complete moles) formalin-fixed, paraffin-embedded tissue samples. RESULTS: The partial and complete moles generally showed similar reactivity with all used lectins. None of lectins reacted with villous cytotrophoblasts, whereas 4 of 7 lectins comprising WGA, LTA, UEA-І and PNA (after pretreatment with neuraminidase) showed a moderate to strong reactivity with villous syncytiotrophoblasts in both partial and complete hydatidiform moles. The villous stroma reacted with all used lectins except VVA. CONCLUSIONS: Our histochemical findings showed a relatively heavy glycosylation of syncytiotrophoblasts of both partial and complete molar tissues, which was prominent in apical portion. This may play a role in their capacity to increase trophoblastic proliferation.

Ki-67 expression in hydatidiform moles and hydropic abortions.

BACKGROUND: Differential diagnosis of hydatidiform moles from non-molar specimens as well as their sub-classification such as complete and partial hydatidiform moles are important for clinical management and accurate risk assessment for persistent gestational trophoblastic disease, but diagnosis based solely on histomorphology suffers from poor interobserver and intraobserver reproducibility. OBJECTIVES: This study was undertaken to determine whether the expression of Ki-67 protein could differentiate these entities. MATERIALS AND METHODS: We performed Ki-67 immunohistochemical staining in 19 molar (8 partial and 11 complete moles) and 10 non-molar (hydropic abortions) formalin-fixed, paraffin-embedded tissue samples. Ploidy analysis using flow cytometry had confirmed diploidy in hydropic abortions and complete moles and triploidy in partial moles. RESULTS: Ki-67 immunoreactivity was assessed in villous cytotrophoblasts, syncytiotrophoblasts and stromal cells. Positive cells were found to be restricted mostly to the villous cytotrophoblasts, while syncytiotrophoblasts showed an absence of immunostaining for Ki-67, and occasional weak nuclear staining was seen in the stromal cells. There was a significant difference in Ki-67 immunoreactivity of cytotrophoblastic cells between hydropic abortions and complete moles (P < 0.001), hydropic abortions and partial moles (P = 0.002) and also between complete and partial moles (P < 0.001). On the other hand, there is significant overlap in the Ki-67 immunoreactivity between complete and partial moles (++ staining category) and between partial moles and hydropic abortions (+ staining category). CONCLUSIONS: Despite the significant differences , Ki-67 immunostaining could not be helpful in distinguishing molar placentas from hydropic abortions as well as partial from complete hydatidiform moles, because there are considerable overlaps between results in different categories.

Diagnostic value of lectins in differentiation of molar placentas.

OBJECTIVES: Distinction of hydatidiform moles from non-molar specimens and subclassification of hydatidiform moles as complete and partial are important for clinical practice, but diagnosis based solely on histomorphology suffers from poor interobserver reproducibility. Nowadays, pathologists rely on molecular techniques, however these methods are technically difficult, relatively expensive, and time consuming, and cannot be applied in all laboratories. Therefore, a relatively easy, time- and cost-effective ancillary tool, would be helpful. This study aimed to assess the role of lectins in differential diagnosis of molar placentas. MATERIALS AND METHODS: Lectin histochemistry with a panel of HRP-conjugated lectins comprising SBA, DBA, MPA, PNA, VVA, UEA-1, LTA, GS-І (B4), and WGA were performed in 20 non-molar (hydropic and non-hydropic spontaneous abortions) and 20 molar (partial and complete moles), formalin-fixed paraffin-embedded tissue samples. On the basis of staining intensity, sections were graded and Kruskal-Wallis non-parametric statistical test was used to compare differences between samples. RESULTS: There was a significant difference between the reactivities of LTA and UEA-І with syncytiotrophoblasts of molar and non-molar specimens (P<0.001). These lectins generally showed a moderate reactivity with syncytiotrophoblasts of molar group but did not react with this cell population in non-molar group. Furthermore, WGA showed relatively increased reaction with syncytiotrophoblasts of molar tissues compared with abortions, however, this did not reach to statistical significance (P=0.07). No major differences were seen in other lectins reactivities between the studied groups. CONCLUSION: The present study showed that UEA-1 and LTA lectins may be used as cytochemical probes in differentiating molar from non-molar placentas, but did not differentiate partial moles from complete moles.