Inclusion Criteria:
* a histologically confirmed diagnosis of NPC
* metastatic NPC that has failed two or more lines of therapy or exhausted standard therapy
* an Eastern Cooperative Oncology Group performance status of 0-2
* age 21-75 years, a life expectancy of more than 3 months
* no prior use of radionuclide therapy
* no prior radiotherapy to more than 25% of bone marrow
* less than 50% of bone marrow involved on 68Ga-DOTATATE scan
* Krenning score ≥ 3 and at least 75% concordance between 68Ga-DOTATATE scan and 18F-FDG PET scan
* at least 1 bidimensionally measurable (2 cm) site of disease.
* A wash-out period of at least 3 weeks from the last dose of prior chemotherapy is required before the administration of the first dose of 177Lu-DOTATATE.
* adequate hematologic, renal, and liver function using standard laboratory measurements
* no history of other malignancy, except treated basal cell and squamous cell skin carcinomas
Exclusion Criteria:
* Serum creatinine \>120 μmol/L or 1.2 mg/dL, or a measured creatinine clearance (or measured glomerular filtration rate (GFR) using plasma clearance methods, not gamma camera-based) of \<50 mL/min.
* Hb concentration \<5.0 mmol/L (\<8.0 g/dL); WBC \<3x10\^9/L (3000/mm3); platelets \<75x10\^9/L (75x10\^3/mm3).
* Total bilirubin \>3 x ULN.
* Serum albumin \<3.0 g/dL unless prothrombin time is within the normal range.
* Pregnancy (see protocol Appendix 6).
* 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) as defined in Appendix 6.
* Peptide receptor radionuclide therapy (PRRT) at any time prior to enrolment in the study.
* Targeted surgery, radiotherapy (external beam), chemotherapy, embolization, interferons, mTOR-inhibitors or other investigational therapy within 3 weeks prior to enrolment in the study.
* Known brain metastases, unless these metastases have been treated and stabilized for at least 24 weeks, prior to enrolment in the study. Patients with a history of brain metastases should have a head CT/MRI to document stable disease prior to enrolment in the study.
* Uncontrolled congestive heart failure (NYHA II, III, IV).
* Uncontrolled diabetes mellitus as defined by a fasting blood glucose \>2 ULN.
* Any patient receiving treatment with short or long acting somatostatin analogs.
* Patients with any other significant medical, psychiatric, or surgical condition, currently uncontrolled by treatment, which may interfere with completion of the study.
* Urinary incontinence.
* Other known co-existing malignancies except non-melanoma skin cancer and carcinoma in situ of the uterine cervix, unless definitively treated and proven no evidence of recurrence for 5 years.
* Patients who have not provided a signed an informed consent form to participate in the study, obtained prior to the start of any protocol related activities.
* Patients who are unable to comply with relevant contact precautions post Lutetium therapy.
* Patients with a synchronous local nasopharyngeal recurrence, with prior high-dose irradiation to the primary tumour.
* Patients with active Hepatitis B (HBsAg positive) or Hepatitis C (HCV Ab positive) infection will be excluded.
* Patients with known history of Human Immunodeficiency Virus (HIV) will be excluded.
