Neuroendocrine tumor of the small intestine diagnosed with trans-abdominal ultrasonography: A case report

INTRODUCTION: Tumors of the small intestine are rare. In addition, clinical symptoms are nonspecific and neoplasm-related symptoms occur late. We report a case of neuroendocrine tumor (NET) of the small intestine that was diagnosed early with trans-abdominal ultrasonography (US). PRESENTATION OF CASE: The patient was a 61-year-old man. Abdominal contrast-enhanced computed tomography (CT) was performed because the patient complained of abdominal pain. The CT showed a tumor lesion in the mesentery. Trans-abdominal US was undertaken to evaluate this tumor lesion, and a tumor lesion of the small intestine was found nearby. A diagnosis of lymph-node metastasis of a small-intestine tumor was made as a preoperative diagnosis. A laparotomy was performed with partial resection of the ileum, together with the small-intestine mesentery including an enlarged lymph node. Histological examination revealed NET of the ileum and lymph-node metastasis. DISCUSSION: With the application of trans-abdominal US, we could diagnose lymph-node metastasis of a small-intestine tumor relatively early and before surgery. CONCLUSION: Trans-abdominal US is useful in the diagnosis of small-intestine NET.