[A Case of Intestinal Metastasis of Testicular Choriocarcinoma Revealed Through Gastrointestinal Bleeding].

A 26-year-old male presented to a hospital with complaints of hemoptysis and right scrotal swelling. Computed tomography (CT) revealed right testicular swelling, multiple lung metastases, and small intestinal wall thickening. The patient's β-human chorionic gonadotropin, alpha-fetoprotein, lactate dehydrogenase, and hemoglobin levels were 103.3 ng/ml, 20.8 ng/ml, 300 U/l, and 11.3 g/dl, respectively. He underwent high orchidectomy after being diagnosed with a testicular tumor and multiple lung metastases. Histopathological examination revealed a mixed germ cell tumor (60% choriocarcinoma, 20% seminoma, 10% embryonal carcinoma, 10% mature teratoma, and 1% yolk sac tumor). As the patient exhibited active gastrointestinal hemorrhage requiring frequent blood transfusions, gastrointestinal endoscopy was performed to investigate its cause. When upper and lower gastrointestinal endoscopies revealed no bleeding, the patient was referred to our hospital for further examination and treatment. A small bowel endoscopy revealed a hemorrhagic jejunal mass. Because endoscopic hemostasis was challenging, we partially resected the small intestine. Pathological findings in the resected lesion were consistent with small intestinal metastasis of the testicular tumor. The tumor markers turned negative after four cycles of BEP and four cycles of TIP chemotherapy. He then underwent resection of the remaining lung tumor, and no residual tumor or recurrence was detected one year later.