This study wil assess somatostatin receptor (SSTR) expression via the uptake of Gallium-68 labelled DOTA-conjugated SSTR targeting peptide using PET/CT imaging in multiple myeloma lesions pre-identified on 18F-FDG PET/CT in order to evaluate the feasibility of molecular radionuclide therapy in refractory and relapsing mutiple myeloma using the Lutetium-177 radiolabelled targeting peptide.

Inclusion Criteria:

• Age above or equal to 18 years
• Written informed consent in accordance with institutional guidelines and obtained prior to any study procedures
• Confirmed diagnosis of multiple myeloma according to the Salmon and Durie criteria
• Has received at least 3 lines of treatment, exposed and refractory (or non-eligible) to the 5 major drugs (lenalidomid, pomalidomid, bortezomib, carfilzomib, daratumumab)
• Life expectancy above 3 months
• Active (relapsing or refractory) and measurable disease (on 18F-FDG PET/CT (performed within 4 weeks prior SSTR PET/CT) and biologically)
• Adequate renal function with GFR above or equal to 30mL/min/1.73m²
• Bone marrow aspiration and biopsy sample available within 30 days prior study enrolment with positive SSTR2 IHC

Exclusion Criteria:

• Pregnant or lactating patients
• Other active neoplastic disease
• Treatment by another molecule that is object of investigation within 30 days prior SSTR PET/CT
• Eastern Cooperative Oncology Group Performance Status above or equal to 3
• Corticoids administration at a therapeutic level (total dose of 160 mg of dexamethasone or equivalent) two weeks prior enrolment