DOTOTATE:  Positive is not always NET

Brandon J Xavier; Christine Marie-Gilligan Schammel; David P Schammel; Steven D Trocha; Eric Farnsworth; Aron Michael Devane

doi:10.5455/ajdi.20230314010926

Abstract
Introduction: Neuroendocrine tumors (NET) are increasing in incidence, and the use of 68Ga-DOTOTATE PET/CT to specifically identify NET has aided with early diagnosis, with 83%-100% sensitivity.
Case: Here, we present a case in which a suspected small bowel obstruction by CT was 68Ga-DOTOTATE PET/CT avid in both the mass and adjacent nodes, suggestive of NET. However, the mass was not consistent with NET during surgical resection and the intra-operative frozen section revealed heterotopic pancreatic tissue and necrotic fat. Surgical resection would have been extensive and morbid; given the lack of a malignant diagnosis, it was aborted.
Discussion: A comprehensive literature review demonstrated few false positive lesions identified by 68Ga-DOTOTATE; most frequently lymph nodes, pancreas, and prostate. Our case is the only reported false positive in a necrotic lesion. These cases highlight the importance of evaluating 68Ga-DOTOTATE PET/CT imaging for NET in the global context and presentation of the patient.

Key words: Neuroendocrine tumor, NET, DOTOTATE, 68Ga-DOTOTATE, false positive