A rare case of primary choriocarcinoma in the sigmoid colon

Figure 1 Findings of preoperative examinations. A: Colonoscopy. B: Barium enema.

Figure 2 Microscopic findings. A, B: HE staining shows the co-existence of choriocarcinoma and adenocarcinoma cells (A: loupe, B: × 200); C: The tumor cells were positive for β-human chorionic gonadotropin (hCGβ) (× 400).

Figure 3 Clinical course of the patient. A, B: Hepatic metastases showed minimal growth until 4 mo after surgery; at 7 mo after surgery; C: The metastases had markedly enlarged, CEA: Carcinoembryonic antigen; AFP: Alpha-fetoprotein.