Expression of nm23-H1 protein in relation to myometrial invasion in complete hydatidiform moles

OBJECTIVE: Although nm23-H1 protein expression has been related to invasion in many cancers, its expression and prognostic significance in complete hydatidiform moles has not yet been investigated. The search for biologic parameters in molar placentas, which are useful for identifying patients who show myometrial invasion of the tumor, is crucial. We examined the clinical significance of nm23-H1 expression in complete hydatidiform mole. METHODS: Sections of 105 cases of complete hydatidiform moles (including 25 cases of invasive mole) and 95 cases of gestational age--matched normal placentas were immunohistochemically stained with anti-nm23-H1 antibody, which recognizes the nm23-H1/NDP kinase A gene product. RESULTS: Expression of nm23-H1 was detected in the cytotrophoblasts and syncytiotrophoblasts of molar placentas and normal placentas, whereas it was not detected in stromal tissue. Expression of nm23-H1 showed a negative relation to invasion, suggesting its use as a potential marker of myometrial invasion in complete hydatidiform moles. CONCLUSION: nm23-H1 expression could be used as a marker for accurate evaluation of myometrial invasion in complete hydatidiform mole.