This is a multicenter, prospective, randomized, placebo-controlled, double-blind, two-parallel groups study comparing lidocaine (experimental group) to placebo (control group). The study protocol was elaborated using the recommendations of the Consolidated Standards of Reporting Trials (CONSORT) Statement.

Inclusion Criteria:

• Patient aged 18 years or older
• Patient suffering from cancer pain refractory to standard opiates (numeric pain intensity scale NPIS >=4/10 after 24 hours of continuous intravenous morphine or oxycodone administration [SOR 2002, analgesics drugs for adults cancer nociceptive pain]), regardless of the nature of the primary cancer]
• Patient suffering from cancer neuropathic or mixed pain (DNA survey score> = 4 [Bouhassira 2004])
• Patient receiving palliative care as defined by French Society of Palliative and Support Care [Charte des Soins Palliatifs, 1996, Act No. 99-477 of 9 June 1999 to guarantee the right of access to palliative care] according to the definition of the World Health Organization (WHO) [World Health Organization. WHO's pain ladder. http://www.who.int/cancer/palliative/painladder/en/. Accessed December 9.2011]
• Patient with histological diagnosis of cancer, locally advanced or metastatic disease
• Patient without curative cancer treatment, and with or without palliative anticancer treatment
• Patient hospitalized in a specific palliative care unit
• Patient with an estimated survival higher than 48 hours (physician estimation) Patient providing written informed consent for participation prior to any study procedures.

Exclusion Criteria:

• Patient with a known hypersensitivity to lidocaine
• Patient with a history of porphyria, arrhythmias, disorders of atrioventricular conduction requiring permanent pacing not yet realized, uncontrolled epilepsy, uncontrolled hypertension
• Patient with hematologic malignancy, abnormal renal, hepatic and cardiac functions
• Patient with a altered sleepiness (Epworth scale score ≤ 16)
• Patient with altered cognitive function (TELECOM scale score> 11) [Arsène 2000]
• Patient not native French speaker Patient defined as vulnerable subject (minor subject, pregnant or nursing woman, subject freedom deprived)