Multifocality in Small Bowel Neuroendocrine Tumors

Neuroendocrine tumors (NETs) account for 30% of small bowel (SB) neoplasms. The objectives of this study were to evaluate the incidence of multifocality in primary small bowel neuroendocrine tumors (SBNETs) and to examine the associated outcomes.

Patients with multifocal SBNET were compared to those with a solitary lesion. Only patients who underwent diagnostic workup and surgical intervention at our institution were included in this study. The primary aim of our study was surgical outcomes and mortality and recurrence. The second aim of our study was to evaluate the utility of double-balloon enteroscopy (DBE) and capsule endoscopy.

Of 178 patients with SBNETs during the study period, 85 met inclusion criteria. The mean age was 61.0 ± 12.6 years and 44.7% were male. The ileum was the primary tumor site for 66 patients (77.7%). Of DBE patients, 28 (62.2%) had additional lesions identified, of which 23 (82.1%) had NET confirmed on pathology. Average tumor size was 1.8 cm and most were well differentiated (89.9%), with Ki-67 of ≥ 2% (65.8%); 74.4% had nodal metastases and 51% of patients had stage IV disease. Forty-six patients (54.1%) had multifocal disease, of whom 37 (80.5%) had an ileal primary. No differences in survival or recurrence were seen for multifocal versus solitary disease.

SBNETs have a high incidence of multifocality. DBE can be used in the preoperative assessment to detect multifocal NET. Multifocality has no impact on survival or recurrence outcomes.