Preoperative PRRT Versus Surgical Cytoreduction in Metastatic Pancreatic Neuroendocrine Tumors to the Liver

Inclusion Criteria: * Metastatic Pancreatic neuroendocrine tumors (PanNET) to the liver * Well- or moderately differentiated (grade 1 or grade 2, Ki- * Ability to aim for equal or greater than 90% hepatic cytoreduction surgically * Proof of SSTR2 expression by uptake of tumor on 68Ga DOTATATE PET CT (Krenning Score on all or a majority of lesions * Age older than 18 years * No Somatostatin Analogues (SSA) or other systemic therapy for 4 weeks prior to starting PRRT, if randomized to arm 2. Exclusion Criteria: * Patient with G3 or poorly differentiated NET (grade 3, Ki-67 \>20%) * Previous liver-directed therapy with Yttrium-90 (TACE/TAE allowed if performed more than 12 months prior to enrollment) * Systemic therapy with Capecitabine and/or Temozolamide within 12 months of enrollment. * No tumor uptake on 68Ga DOTATATE PET CT * Liver tumor burden \> 50% (as defined by CT or MRI) * Signs of early liver failure (T-Bilirubin \>3, INR \> 1.5, Albumin \<3.0 g/dL unless prothrombin time is within the normal range) or cirrhosis or ascites * calculated by the Cockroft Gault method, eventually confirmed by measured creatinine clearance * (or measured glomerular filtration rate (GFR) using plasma clearance methods, not gamma * camera-based) \<50 mL/min (the measured creatinine clearance / GFR is required only as - confirmatory exam). * 2\. Hb concentration \<5.0 mmol/L (\<8.0 g/dL); WBC \<2x109/L (2000/mm3); platelets \<75x109/L - (75x103/mm3). * Known brain metastases, unless these metastases have been treated and stabilized. * Uncontrolled congestive heart failure (NYHA II, III, IV). * Uncontrolled diabetes mellitus as defined by a fasting blood glucose \>2 ULN. * Pregnancy or lactation. * For female patients of childbearing potential (defined as \< 2 years after last menstruation and not surgically sterile) and male patients, who are not surgically sterile or with female partners of childbearing potential: absence of effective, non-hormonal means of contraception (intrauterine contraceptive device, barrier method of contraception in conjunction with spermicidal gel). - Prior external beam radiation therapy to more than 25% of the bone marrow. * Current spontaneous urinary incontinence making impossible the safe administration of the radioactive IMP. * Other known co-existing malignancies except non-melanoma skin cancer and carcinoma in situ of the uterine cervix, unless definitively treated and with no evidence of recurrence. * Patients who have not provided a signed informed consent form to accept this treatment. * Poor renal function * Quality Unit language added * editorial changes