Abstract
Background: Gestational trophoblastic tumors and tumor-like lesions are derived from trophoblastic cells and are composed of different trophoblastic subpopulations. Recent histopathological and molecular studies indicate that these trophoblast-related lesions recapitulate the differentiation of normal trophoblast in early placenta development. Objective: To distinguish trophoblastic tumors from other types of neoplastic disease and differential diagnosis among different types of trophoblastic lesion are important as far as treatment plans are concerned. Methods: This article reviews the histopathological features of these trophoblastic lesions and recent advances in the trophoblast-associated markers, which are helpful in differential diagnosis. Results/conclusion: Histopathologic features serve as the basis in the diagnosis of various types of trophoblastic lesion. In difficult cases, a stepwise immunohistochemistry approach, called trophogram, may prove useful in assisting the differential diagnosis.