D. Harms and G. Janka-schaub, Co-operative study group for childhood acute lymphoblastic leukemia (COALL): long-term follow-up of trials 82, 85, 89 and 92, Leukemia, vol.14, issue.12, pp.89-92, 2000.
DOI : 10.1038/sj.leu.2401974

Y. Ravindranath, M. Chang, C. Steuber, D. Becton, G. Dahl et al., Pediatric Oncology Group (POG) studies of acute myeloid leukemia (AML): a review of four consecutive childhood AML trials conducted between 1981 and 2000, Leukemia, vol.87, issue.12, pp.2101-2116, 1981.
DOI : 10.1097/00004872-200107000-00013

C. Mason and G. Krueger, Thioguanine for refractory psoriasis: A 4-year experience, Journal of the American Academy of Dermatology, vol.44, issue.1, pp.67-72, 2001.
DOI : 10.1067/mjd.2001.109296

M. Dubinsky, P. Hassard, E. Seidman, L. Kam, M. Abreu et al., An Open-Label Pilot Study Using Thioguanine as a Therapeutic Alternative in Crohn's Disease Patients Resistant to 6-Mercaptopurine Therapy, Inflammatory Bowel Diseases, vol.7, issue.3, pp.181-189, 2001.
DOI : 10.1097/00054725-200108000-00001

K. Herrlinger, W. Kreisel, M. Schwab, J. Schoelmerich, W. Fleig et al., 6-Thioguanine - efficacy and safety in chronic active Crohn's disease, Alimentary Pharmacology and Therapeutics, vol.122, issue.4, pp.503-508, 2003.
DOI : 10.1136/gut.49.5.656

K. Herrlinger, P. Deibert, M. Schwab, W. Kreisel, C. Fischer et al., Remission maintenance by tioguanine in chronic active Crohn's disease, Alimentary Pharmacology and Therapeutics, vol.118, issue.12, pp.1459-1464, 2003.
DOI : 10.1136/gut.48.5.642

P. Deibert, K. Dilger, C. Fischer, U. Hofmann, S. Nauck et al., High variation of tioguanine absorption in patients with chronic active Crohn's disease, Alimentary Pharmacology and Therapeutics, vol.3, issue.2, pp.183-189, 2003.
DOI : 10.1046/j.1365-2036.2000.00812.x

B. Bonaz, J. Boitard, P. Marteau, M. Lemann, B. Coffin et al., Tioguanine in patients with Crohn's disease intolerant or resistant to azathioprine/mercaptopurine, Alimentary Pharmacology and Therapeutics, vol.18, issue.4, pp.401-408, 2003.
DOI : 10.1002/(SICI)1097-0142(19990915)86:6<1080::AID-CNCR26>3.0.CO;2-5

L. Derijks, D. De-jong, L. Gilissen, L. Engels, P. Hooymans et al., 6-Thioguanine seems promising in azathioprine- or 6-mercaptopurine-intolerant inflammatory bowel disease patients, European Journal of Gastroenterology & Hepatology, vol.15, issue.1, pp.63-67, 2003.
DOI : 10.1097/00042737-200301000-00011

M. Dubinsky, E. Feldman, M. Abreu, S. Targan, and E. Vasiliauskas, Thioguanine: a potential alternate thiopurine for IBD patients allergic to 6-mercaptopurine or azathioprine, The American Journal of Gastroenterology, vol.83, issue.3, pp.1058-1063, 2003.
DOI : 10.1016/S0140-6736(87)91478-4

T. Cheung and T. Florin, 6-thioguanine: a new old drug to procure remission in inflammatory bowel disease, Internal Medicine Journal, vol.31, issue.1-2, pp.44-46, 2003.
DOI : 10.1046/j.1445-5994.2003.00321.x

A. Teml, M. Schwab, M. Harrer, W. Miehsler, E. Schaeffeler et al., A prospective, open-label trial of 6-thioguanine in patients with ulcerative or indeterminate colitis, Scandinavian Journal of Gastroenterology, vol.126, issue.10, pp.1205-1213, 2005.
DOI : 10.1080/00365520510023369

N. De-boer, L. Derijks, L. Gilissen, D. Hommes, L. Engels et al., On tolerability and safety of a maintenance treatment with 6-thioguanine in azathioprine or 6-mercaptopurine intolerant IBD patients, World Journal of Gastroenterology, vol.11, issue.35, pp.5540-5544, 2005.
DOI : 10.3748/wjg.v11.i35.5540

P. Griner, A. Elbadawi, and C. Packman, Veno-Occlusive Disease of the Liver After Chemotherapy of Acute Leukemia, Annals of Internal Medicine, vol.85, issue.5, pp.578-582, 1976.
DOI : 10.7326/0003-4819-85-5-578

R. Gill, G. Onstad, J. Cardamone, D. Maneval, and H. Sumner, Hepatic Veno-Occlusive Disease Caused by 6-Thioguanine, Annals of Internal Medicine, vol.96, issue.1, pp.58-60, 1982.
DOI : 10.7326/0003-4819-96-1-58

N. Krivoy, R. Raz, A. Carter, and G. Alroy, Reversible Hepatic Veno-Occlusive Disease and 6-Thioguanine, Annals of Internal Medicine, vol.96, issue.6_part_1, p.788, 1982.
DOI : 10.7326/0003-4819-96-6-788_1

S. Stoneham, L. Lennard, P. Coen, J. Lilleyman, and V. Saha, Veno-occlusive disease in patients receiving thiopurines during maintenance therapy for childhood acute lymphoblastic leukaemia, British Journal of Haematology, vol.100, issue.1, pp.100-102, 2003.
DOI : 10.1046/j.1365-2141.2003.04578.x

N. Key, P. Kelly, P. Emerson, R. Chapman, N. Allan et al., OESOPHAGEAL VARICES ASSOCIATED WITH BUSULPHAN-THIOGUANINE COMBINATION THERAPY FOR CHRONIC MYELOID LEUKAEMIA, The Lancet, vol.330, issue.8567, pp.1050-1052, 1987.
DOI : 10.1016/S0140-6736(87)91478-4

M. Dubinsky, E. Vasiliauskas, H. Singh, M. Abreu, K. Papadakis et al., 6-thioguanine can cause serious liver injury in inflammatory bowel disease patients, Gastroenterology, vol.125, issue.2, pp.298-303, 2003.
DOI : 10.1016/S0016-5085(03)00938-7

J. Seiderer, C. Zech, W. Reinisch, M. Lukas, J. Diebold et al., A multicenter assessment of liver toxicity by MRI and biopsy in IBD patients on 6-thioguanine, Journal of Hepatology, vol.43, issue.2, pp.303-309, 2005.
DOI : 10.1016/j.jhep.2005.02.051

S. Geller, M. Dubinsky, F. Poordad, E. Vasiliauskas, A. Cohen et al., Early Hepatic Nodular Hyperplasia and Submicroscopic Fibrosis Associated With 6-Thioguanine Therapy in Inflammatory Bowel Disease, The American Journal of Surgical Pathology, vol.28, issue.9, pp.1204-1211, 2004.
DOI : 10.1097/01.pas.0000128665.12063.97

L. Gilissen, L. Derijks, A. Driessen, L. Bos, P. Hooymans et al., Toxicity of 6-thioguanine: no hepatotoxicity in a series of IBD patients treated with long-term, low dose 6-thioguanine, Digestive and Liver Disease, vol.39, issue.2, pp.156-159, 2007.
DOI : 10.1016/j.dld.2006.10.007

B. Piel, S. Vaidya, D. Lancaster, M. Taj, and K. Pritchard-jones, Chronic hepatotoxicity following 6-thioguanine therapy for childhood acute lymphoblastic leukaemia, British Journal of Haematology, vol.123, issue.3, pp.410-411, 2004.
DOI : 10.1111/j.1365-2141.2004.04919.x

R. De-bruyne, B. Portmann, M. Samyn, S. Bansal, A. Knisely et al., Chronic liver disease related to 6-thioguanine in children with acute lymphoblastic leukaemia, Journal of Hepatology, vol.44, issue.2, pp.407-410, 2006.
DOI : 10.1016/j.jhep.2005.06.020

N. De-boer, W. Reinisch, A. Teml, A. Van-bodegraven, M. Schwab et al., 6-Thioguanine Treatment in Inflammatory Bowel Disease: A Critical Appraisal by a European 6-TG Working Party, Digestion, vol.73, issue.1, pp.25-31, 2006.
DOI : 10.1159/000091662

A. Miller, B. Hoogstraten, M. Staquet, and A. Winkler, Reporting results of cancer treatment, Cancer, vol.11, issue.1, pp.207-214, 1981.
DOI : 10.1002/1097-0142(19810101)47:1<207::AID-CNCR2820470134>3.0.CO;2-6

P. Reshamwala, D. Kleiner, and T. Heller, Nodular regenerative hyperplasia: Not all nodules are created equal, Hepatology, vol.10, issue.1, pp.7-14, 2006.
DOI : 10.1002/hep.21258

J. Kuchenbecker, H. Dick, K. Schmitz, and W. Behrens-baumann, Use of Internet Technologies for Data Acquisition in Large Clinical Trials, Telemedicine Journal and e-Health, vol.7, issue.1, pp.73-76, 2001.
DOI : 10.1089/153056201300093976

J. Lindh, M. Kublickas, M. Westgren, and A. Rane, Internet based clinical trial protocols - as applied to a study of warfarin pharmacogenetics, British Journal of Clinical Pharmacology, vol.24, issue.5, pp.482-487, 2004.
DOI : 10.1136/bmj.327.7413.484

N. De-boer, L. Gilissen, L. Derijks, G. Den-hartog, B. Westerveld et al., Hepatotoxicity of long-term and low-dose 6-thioguanine in IBD patients, Gastroenterology, vol.130, pp.202-203, 2006.

L. Derijks, L. Gilissen, N. De-boer, and C. Mulder, 6-Thioguanine-related hepatotoxicity in patients with inflammatory bowel disease: Dose or level dependent?, Journal of Hepatology, vol.44, issue.4, pp.821-822, 2006.
DOI : 10.1016/j.jhep.2005.11.049

N. De-boer, G. De, A. Wilhelm, C. Mulder, and A. Van-bodegraven, On the limitation of 6-tioguaninenucleotide monitoring during tioguanine treatment, Alimentary Pharmacology and Therapeutics, vol.27, issue.5, pp.447-451, 2005.
DOI : 10.1172/JCI200316432

L. Derijks, L. Gilissen, L. Engels, L. Bos, P. Bus et al., Pharmacokinetics of 6-Thioguanine in Patients With Inflammatory Bowel Disease, Therapeutic Drug Monitoring, vol.28, issue.1, pp.45-50, 2006.
DOI : 10.1097/01.ftd.0000179839.71138.6d

D. Lancaster, L. Lennard, R. K. Vora, A. Lilleyman, and J. , Thioguanine versus mercaptopurine for therapy of childhood lymphoblastic leukaemia: a comparison of haematological toxicity and drug metabolite concentrations, British Journal of Haematology, vol.19, issue.(Suppl. 2), pp.439-443, 1998.
DOI : 10.1046/j.1365-2141.1998.00812.x

K. Herrlinger, K. Fellermann, C. Fischer, W. Kreisel, P. Deibert et al., Thioguanine-nucleotides do not predict efficacy of tioguanine in Crohn's disease, Alimentary Pharmacology and Therapeutics, vol.126, issue.1, pp.1269-1276, 2004.
DOI : 10.1016/0006-2952(71)90046-3

J. Duley and T. Florin, Thiopurine Therapies, Therapeutic Drug Monitoring, vol.27, issue.5, pp.647-654, 2005.
DOI : 10.1097/01.ftd.0000169061.52715.3e

P. Khalil, N. Erb, M. Khalil, G. Escherich, and G. Janka-schaub, RETRACTED: Validation and application of a high-performance liquid chromatographic-based assay for determination of the inosine 5???-monophosphate dehydrogenase activity in erythrocytes, Journal of Chromatography B, vol.842, issue.1, pp.1-7, 2006.
DOI : 10.1016/j.jchromb.2006.04.040

F. Daniel, J. Cadranel, P. Seksik, A. Cazier, D. Van-huyen et al., Azathioprine induced nodular regenerative hyperplasia in IBD patients, Gastroent??rologie Clinique et Biologique, vol.29, issue.5, pp.600-603, 2005.
DOI : 10.1016/S0399-8320(05)82136-0

D. Chatelain, H. Van-damme, F. Brazier, G. Geslin, E. Bartoli et al., High 6-thioguanine nucleotide (6-TGN) levels after azathioprine treatment are not associated with increased risk for serious hepatic damage, Gastroenterology, vol.128, pp.305-306, 2005.

G. Vernier-massouille, J. Cosnes, M. Lemann, P. Marteau, W. Reinisch et al., Nodular regenerative hyperplasia in patients with inflammatory bowel disease treated with azathioprine, Gut, vol.56, issue.10, p.15, 2007.
DOI : 10.1136/gut.2006.114363

URL : https://hal.archives-ouvertes.fr/hal-00815835

I. Wanless, micronodular transpormation (nodular regenerative hyperplasia) of the liver: A report of 64 cases among 2,500 autopsies and a new classification of benign hepatocellular nodules, Hepatology, vol.6, issue.5, pp.787-797, 1990.
DOI : 10.1002/hep.1840110512

C. Zech, J. Seiderer, W. Reinisch, T. Ochsenkuhn, W. Schima et al., Thioguanin-induced nodular regenerative hyperplasia of the liver-ROC analysis of different MR techniques, European Radiology, vol.73, issue.Suppl 6, pp.1898-1905, 2007.
DOI : 10.1007/s00330-006-0544-3