Performance of capsule endoscopy for the detection of small intestinal neuroendocrine tumors in familial carcinoid: a prospective single-site study

Abstract

Background and AimsSmall bowel neuroendocrine tumors are slow growing, clinically silent tumors whose prognosis depends on disease stage. Members of kindreds with a familial form of small intestine neuroendocrine tumors (SI-NET) represent a high-risk population for whom early detection improves disease outcome. The aim was to determine the utility of small bowel capsule endoscopy (SB-CE) for screening high-risk asymptomatic relatives from kindreds with familial carcinoid. Methods174 asymptomatic subjects with a family history (≥ 2 family members) of SI-NET were screened under Protocol NCT00646022, Natural History of Familial Carcinoid Tumor at the National Institutes of Health. All patients were imaged with SB-CE and 18F-DOPA PET/CT and results were independently analyzed. Patients with a positive imaging study underwent surgical exploration. ResultsThirty-five of 174 asymptomatic subjects screened for SI-NET were positive on either SB-CE or 18F-DOPA PET. Thirty-two of 35 patients with a positive study were confirmed at surgery. SB-CE was positive in 28 of 32 patients with confirmed tumors for a per patient sensitivity of 87.5%. SB-CE had a specificity of 97.3% and a negative predictive value (NPV) of 96.5%. The average tumor number and size was 7.7 and 5.0 mm, respectively, and 81.2% of patients had multiple tumors. 18F-DOPA PET/CT imaging had a similar sensitivity of 84% versus surgery. ConclusionsSB-CE is a sensitive and specific method comparable to 18F-DOPA PET/CT for screening high-risk patients with familial SI-NET.