SUV on 68Ga-DOTATATE PET/CT and Ki-67 Index in Neuro-Endocrine Tumors

Positron emission tomography/computed tomography (PET/CT) is an advanced nuclear medicine scan. This technology allows precise and early cancer to be visualized and measured on whole body images. Patients with Neuro-Endocrine tumors (NETs), require specialized molecular imaging to stage, re-stage and assess eligibility and response to therapy. 68Ga-DOTATATE is a nuclear medicine imaging agent that is not yet approved by Health Canada but used extensively throughout the world. The Ki-67 index, a marker of cell proliferation in NETs, is one of the most important prognostic factors in this disease. The objective of this study is to evaluate if the maximal standard uptake value (SUVmax) on PET/CT in NETs inversely correlates with Ki-67 score on initial biopsy. If this hypothesized correlation between SUV and Ki-67 score is reproduced, then DOTATATE would serve as a non-invasive method to assess cellular proliferation and therefore prognosis of these patients.