ABSTRACT
PURPOSE: To explore the utility of p57, c-erbB-2, CD 117, and Bel-2 immunostaining in the differential diagnosis of complete hydatidiform mole (CHM), partial hydatidiform mole (PHM), and hydropic abortion (HA). MATERIALS AND METHODS: Immunohistochemical expression of the p57, c-erbB-2, CD117, and Bel-2 proteins were investigated semi-quantitatively using paraffin-embedded tissue sections from histologically unequivocal cases of CHM (n = 20), PHM (n = 23), and HA (n = 17). RESULTS: All cases of CHM exhibited a striking absence of p57 expression. The percentage of positive p57 staining was similar between PHMs (73.9%) and HAs (76.5%) (p >0.05). The comparison of c-erbB-2 expression revealed a significantly higher percentage of positive c-erbB-2 staining in CHMs (45%) compared with that in PHMs (8.7%) and HAs (5.9%) (p = 0.006 and 0.01, respectively). The CD 117 expression pattern (immunoreactivity score, percentage of positive cells, and staining intensity) was significantly lower in HAs compared with that in PHMs and CHMs (p < 0.05 for all). A significantly increased Bel-2 expression pattern was observed in HAs compared with that in PHMs and CHMs (p < 0.05 for all). CONCLUSION: Immunohistochemical examination of p57, c-erbB-2, CD 117, and Bel-2 expression represents a relatively simple, reliable, and cost-efficient procedure to definitively distinguish among CHM, PHM, and HA.
