Role of (68)Ga-DOTATOC PET-CT in the diagnosis and staging of pancreatic neuroendocrine tumours.

OBJECTIVE: The objective of the present study was to evaluate the role of (68)Ga-DOTA(0)-Phe(1)-Tyr(3)-octreotide ((68)Ga-DOTATOC) positron emission tomography computed tomography (PET-CT) for detection and staging of pancreatic neuroendocrine tumours (NETs).

METHODS: Twenty patients with clinically suspected and/or histopathologically proven pancreatic NET underwent (68)Ga-DOTATOC PET-CT imaging for staging and /or localisation of primary lesion. They also underwent contrast enhanced CT (CECT) and 8 patients underwent (18)F-FDG PET-CT. SUVmax of primary and metastatic lesions were measured. Results were verified with histopathology for primary tumour and with clinical follow up/MRI and /or biopsy for metastatic disease. Results of (68)Ga-DOTATOC PET-CT were compared to CECT and (18)F-FDG PET-CT.

RESULTS: (68)Ga-DOTATOC PET-CT correctly localised primary in all 20, CECT in 15 and (18)F-FDG PET-CT in 2 patients. (68)Ga-DOTATOC PET-CT demonstrated metastases in 13 patients, CECT in 7 and (18)F-FDG PET-CT in 2. (68)Ga-DOTATOC PET-CT emerged as the best investigation with 100% sensitivity and PPV for detecting primary tumour and metastatic disease. The detection rate of CECT was lower than (68)Ga-DOTATOC PET-CT, both for primary tumour (20vs.15) or metastatic disease (13vs.7). (18)F-FDG PET-CT performed poorly for primary and metastasis.

CONCLUSION: Ga-DOTATOC PET-CT is a very useful imaging investigation for diagnosing and staging pancreatic NET.