Incidental Diagnosis of a Carcinoid Tumor of the Ileum using Contrast-Enhanced Ultrasound (CEUS)

Introduction

Carcinoids of the gastrointestinal system are a rare manifestation of highly vascularized tumors that arise from enterochromaffin cells with a low incidence rate of approx. 2/100 000 people and a mean age of diagnosis in the 6th life decade (Crocetti E, Paci E. Eur J Cancer Prev 2003;12:191–4). About 42% of all gastrointestinal carcinoids occur in the small bowel, followed by carcinoids of the appendix (about 23%) and of the stomach (about 9%) (Modlin IM et al. Cancer 2003;97: 934–59). Tumors greater than 2 cm in size normally show classic clinical signs and symptoms and tend to develop metastases. Typical clinical symptoms include abdominal cramping, diarrhea and flushing (Caplin ME et al. Lancet 1998;352:799–805). Because of the low clinical incidence and the small tumor size, initial diagnosis of this tumor entity is difficult. Diagnostic options include all available imaging modalities, including (contrast-enhanced) ultrasound (CEUS) and color Doppler, as well as (PET) computed tomography and magnetic resonance imaging. With the broader availability of CEUS in the clinical routine and improved imaging quality in recent years, ultrasound has the potential to be a viable imaging option for the evaluation of suspicious lesions in the terminal ileum (Rickes S et al. Med Klin (Munich). 2009;104(7):564-6.)