Expression of Inhibin/Activin Subunits, Sialyl-Lewis A (CA 19-9, sLea) and Sialyl-Lewis X (sLex) Carbohydrate Antigens in a Hydatidiform Mole with Persistent Polymorphic Trophoblastic Hyperplasia

Abstract

The persistence of polymorphic trophoblastic hyperplasia in a hydatidiform mole is an extremely rare condition. Its early diagnosis is essential since such cases can transform into invasive tumours. Materials and Methods: The paraffin-embedded biopsies were routinely stained with HE. Immunohistochemical staining reactions were performed with monoclonal antibodies against inhibin-α, inhibin-βA and inhibin-βB subunits. Additional immunohistochemical reaction was performed with, Sialyl-Lewis A and Sialyl-Lewis X and glycodelin. Results: Large villi and hydatidiform villi with ranging syncyctio- and cytotrophoblasts were seen. Intervillous proliferating trophoblasts showed cell- and nuclear polymorphy with invasion of the myometrium wall. The immunohistochemistry exhibited strong positivity for inhibin-α, inhibin-βA and inhibin-βB subunits in trophoblastic tissue, while the decidua was negative. Sialyl-Lewis A and Sialyl-Lewis X showed no or minimal focal immunohistochemical reaction. Conclusion: A complete hydatidiform mole with hyperplasia and proliferation presents a high risk of developing a persistent (eventually metastatic) trophoblastic disorder and, in up to 15% of the cases, an invasive mole. In 2.5 % of the cases it can transform into a choriocarcinoma. Since the inhibin/activin subunits reacted positively with trophoblastic tissue, they might be a useful diagnostic marker for hydatidiform mole with persistence of polymorphic trophoblastic hyperplasia.