Genetic, Neurophysiological and Psychological Risk Factors for Neuropathic Pain

This new study will enroll patients undergoing mastectomy or thoracotomy for cancer. They will be three cohorts :

• one prospective cohort constituted of women undergoing breast surgery in René Huguenin Hospital (Saint Cloud) and followed for up to one year after surgery.
• another cross sectional cohort constituted of patient association (Seintinelle) including women operated up to 2 years previously from breast surgery.
• One prospective cohort constituted of women or men undergoing thoracotomy in Foch hospital (Suresnes) and followed for up to one year after surgery.

The main objectives of these cohorts will be to detect potential genetic, neurophysiological, psychological and cognitive risk factors for the development of chronic postsurgical neuropathic pain.

These patients will questioned about demographics, age, sex, body mass index. A large neuropsychological and psychological battery of tests will be conducted. Sensory function will assessed using quantitative sensory testing. Biological samples will analyse potential genetic factors in the development of neuropathic pain after surgery. Conditioned pain modulation, threshold tracking and quantitative sensory testing will also be assessed in subgroup of patients.

The prospective cohort will be assessed before surgery then 3, 6 and 12 months after surgery. The cross sectional cohort will be assessed during one to two visits in hospital.

Inclusion criteria

• Patients undergoing surgery for breast cancer or thoracotomy for lung cancer followed during the course of the study or patients from the French cohort Seintinelle already operated from breast surgery over the past 2 years.

Exclusion criteria

• Patients are not included if they have clinically significant or unstable psychiatric or somatic conditions (e.g. major depression, psychosis, uncontrolled diabetes mellitus or hypertension, neurological disorders, immune disease, body mass index > 45), past or present substance abuse or any cognitive deterioration based on past medical history, semi-structured interview and lack of completion or full understanding of questionnaires.
• Bilateral mastectomy (for women undergoing breast surgery)
• Presence of pain before surgery