Exaggerated Placental Site Mimicking Gestational Trophoblastic Neoplasia: A Multimodality Imaging and Histopathological Case Report

Abstract

Background: Exaggerated placental site (EPS) is a benign, physiologic infiltration of intermediate trophoblasts that can radiologically mimic malignant gestational trophoblastic neoplasia (GTN) (Wijesinghe, 2025, Yordanov et al., 2020). Case Presentation: A 38-year-old female presented with suspected abnormal uterine bleeding (AUB) and a working diagnosis of GTN. Multimodality imaging, including ultrasound, magnetic resonance imaging (MRI), and computed tomography (CT), revealed a highly vascular, infiltrative uterine mass. Serum Beta-HCG was elevated. The patient underwent a hysterectomy. Histopathological examination ruled out malignancy, diagnosing products of conception with an exaggerated placental site. Discussion and Conclusion: Exaggerated Placental Site (EPS)—a benign, self-limiting physiological reaction—can perfectly mimic malignant Gestational Trophoblastic Neoplasia (GTN) both clinically and on advanced radiological imaging (Menczer et al., 1999, Yordanov et al., 2020). By detailing a case where MRI and CT scans falsely flagged a uterine mass as an aggressive malignancy due to its deep myometrial infiltration and robust vascularity, the authors underscore the limitations of relying solely on radiological evaluations. Ultimately, this report reinforces that histopathological examination is strictly required to definitively differentiate EPS from true neoplasms, which is a critical step to prevent misdiagnosis and protect patients from receiving unnecessary oncological treatments like systemic chemotherapy.