Intrathecal Morphine Administration Using Implantable Pump With Continuous or Programmable Flow

Inclusion Criteria: * Age \> or = 18 years old. * Patient with advanced cancer. * Patient with severe pain, i.e. a mean daily pain score \> or = 5 on an numeric rating scale. * Failure of optimal conventional analgesic therapy : either due to intolerable adverse events or to lack of efficacy, i.e. after having tried opioid rotation techniques, different way of administration, use of rapid-acting narcotics to control acute episodes of pain, use of intravenous morphine by PCA pump. * Possibility of return home * Dated and signed informed consent form. Exclusion Criteria: * Patient's refusal to participate in the study. * Ongoing pregnancy. * Ongoing systemic infection. * Injection site infection. * Estimated survival less than 90 days. * Allergy or intolerance to morphine. * Contraindication to implantation of an intrathecal catheter. * Patient treated with a powerful CYP1A2 inhibitor, such as fluvoxamine or enoxacin. * Intrathecal chemotherapy planned.