Complete response to multidisciplinary therapy in a patient with primary gastric choriocarcinoma

Figure 2 Pathological findings (hematoxylin/eosin staining and immunohistochemical staining). A: The tumor had two components, as indicated by small boxes with solid and dashed lines. Hematoxylin/eosin (HE) × 40; B: In the area marked by a solid line in panel A, unusual multinucleated giant cells in a characteristic dimorphic plexiform pattern associated with hemorrhage and necrosis were observed. HE × 100; C: Atypical mononucleated cells demonstrated a solid and sheet growth pattern in the area marked by a dashed line in panel A. HE × 100; D, E: Tumor cells were diffusely positive for β-human chorionic gonadotropin (hCG) and focally positive for human placental lactogen (HPL) in the area marked by a solid line in panel A. HE × 200; F, G: The tumor cells were positive for beta-human chorionic gonadotropin and placental alkaline phosphatase (PALP) in the area marked by a dashed line in panel A. HE × 200; H: Immunoreactivity was focally positive for carcinoembryonic antigen (CEA). HE × 100.