IMMUNOHISTOCHEMISTRY IN THE DIAGNOSIS OF THE GESTATIONAL TROPHOBLASTIC DISEASE

Objective. The gestational trophoblastic disease summarizes all types of hydatidiform moles, placental site trophoblastic tumor and chorioca rcinoma. It is of clinical relevance to distinguish between complete h ydatidiform mole and partial hydatidiform mole to predict prognosis of recurrency of molar pregnancy and the risk of the development of mali gn and metastatic gestational trophoblastic disease. Differential diag nosis of choriocarcinoma versus placental site trophoblastic tumor, ca rcinoma or sarcoma with low differentiation can cause problems in bord erline-cases. The present study investigates the value of immunohistoc hemistry in the diagnosis of gestational trophoblastic disease. Method . Nine cases of patients with complete hydatidiform mole, 20 cases of partial hydatidiform mole and seven cases of choriocarcinoma were anal yzed for the immunohistochemical reaction with antibodies against huma n choriogonadotropin (hCG), human placental lactogen (hPL), placental alkaline phosphatase (FLAP), cytokeratine and vimentin. Results. Compl ete hydatidiform mole shows strong expression of hCG and weak expressi on of FLAP. Weak hCG and strong FLAP expression is found in partial hy datidiform mole. Choriocarcinoma presents strong expression of hCG and weak expression of hPL and FLAP. All tissues show positive reaction w ith anticytokeratine and negative reaction with anti-vimentin. Conclus ion. Our study proves immunohistochemistry as useful tool for differen tial diagnosis in borderline cases of gestational trophoblastic diseas e.