OBJECTIVETo investigate the role of p57 and p53 immunohistochemistry in the differential diagnosis of hydropic abortion, partial hydatidiform mole and complete hydatidiform mole.

METHODSImmunohistochemical stains (EnVision method) for p57 and p53 were performed in tissue samples of normal placenta chorionic villi (n=10), abortion chorionic villi (n=12), partial hydatidiform (n=23) and complete hydatidiform moles (n=20).

RESULTSThe expression of p57 was predominantly localized in the nuclei of villous cytotrophoblasts and stromal cells. The positive rates of p57 in normal placenta, hydropic abortion and partial hydatidiform mole were 10/10, 12/12, and 100% (23/23), respectively, with no significant difference among the groups (P>0.05). However, none of the complete hydatidiform moles analyzed exhibited p57 positivity in cytotrophoblasts and stromal cells. There was a significant difference between partial and complete hydatidiform moles (P<0.05). The expression of p53 was observed in the nuclei of cytotrophoblastic cells and intermediate trophoblasts. No p53 expression was seen in normal placenta and only 1 of 12 hydropic abortion showed p53 positivity. The positive rates of p53 expression in partial and complete hydatidiform mole were 60.9% (14/23) and 85.0% (17/20) respectively. It was significantly higher in partial hydatidiform mole than that in hydropic abortion. A significant difference was also found between partial and complete hydatidiform moles (P<0.05).

CONCLUSIONSOur findings confirm that p57 immunohistochemistry assists the differential diagnosis of complete hydatidiform mole from partial hydatidiform mole. Expression of p53 may be helpful in distinguishing partial hydatidiform mole from hydropic abortion.