The referent algologist informs the patient of the retained offer in the pain multidisciplinary consultation meeting. Following the consultation, the investigator sees the patient to explain the study and to verify all the inclusion and non-inclusion criteria, to give and explain the information note and to be sure of the non-opposition.

A psychologist comes in each centre to realise the semi-directed interviews before putting on the catheter, at 1 month and at 3 months after the establishment of this technic. The interview will be recorded with the agreement of the patient then totally transcribed. A double analysis will allow to extract the verbatim record and to construct the thematic tree with under-themes.

The same day of the interviews, 4 questionnaires will allow to evaluate to the 3 periods of measurement (before putting on the catheter, M1 et M3) : the mean pain of the past 24 hours by the BPI-SF (Brief Pain Inventory-short form) questionnaire, the anxiety and the depression by the HAD (Hospital Anxiety and Depression scale) questionnaire, the quality of life by the QLQ-C30 questionnaire, the catastrophism by the PCS (Pain Catastrophizing Scale) questionnaire.

The evaluation by the patient and the algologist of the global clinic improvement after the establishment of the analgesic treatment by intrathecal way will be realised at M1 and M3 with the help of the questionnaire P-GIC and C-GIC (Patient or Clinical- Global Impression of Change).

The study does not interfere with the treatment of the patient and his usual care. No biological exams or imagery will be realise in this study.