Main objectives are:
* Description of the clinical and histological characteristics, treatment and evolution of these NHL.
* Study their physiopathology by immunological, virologic and molecular studies.
The study included prospective or retrospective patients with B- Cell Non-Hodgkin lymphomas (NHL) associated with chronic hepatitis C. The patients are diagnosed or in remission of lymphoma, in relapse or failure of treatments.
The enrolment period is 6 years and the total study lasts 8 years.
* "Prospective patients" are followed every 6 months during one year, and all the years during 2 or 5 years.
* "Retropective patients" are followed all the years during 2 or 5 years. At each follow-up, a blood sample of 50ml is withdrawn allowing ancillary studies.
The enrollment is estimated at 140 patients.