The proposed clinical trial will be a Phase I/II, diagnostic imaging, controlled, open label, single site, single dose clinical trial in a broad cross-section of patients with known or suspected somatostatin receptor positive tumours. All participants will be imaged with [68]Ga-HA-DOTATATE PET/CT for uptake by somatostatin receptor positive tumours. A safety evaluation will be conducted on the first 10 consecutively enrolled participants (safety sub-group), consisting of vital signs, haematology and SMA-12 serum biochemistry profile (pre-injection and post-imaging), and an adverse event (AE) assessment (up to 24 hours) after [68]Ga-HA-DOTATATE imaging. The safety evaluation for the remaining participants will consist of an AE assessment (up to 24 hours) after [68]Ga-HA-DOTATATE imaging. The efficacy evaluation will include [68]Ga-HA-DOTATATE scan clinical accuracy compared to standard of care cross-sectional images and values published in the literature.