2. Presence of somatostatin receptor positive tumour(s) [either histologically or radionuclide imaging proven (Octreoscan or Ga-68 Dotatate / NETSPOT)], with at least 1 tumour site reliably evaluable by CT or MRI of at least 1.5 cm (smallest dimension) with respect to RECIST criteria (the target lesion) within 26 weeks of enrolment.