Role of glutathione-S-transferase (GST) polymorphisms in patients with advanced Hodgkin lymphoma: results from the HD2000 GISL trial.

Abstract
Polymorphisms of the Glutathione-S Transferase (GST) family may influence the prognosis in lymphoma patients. We aimed to validate the impact of GSTT1 and GSTM1 deletions and of the GSTP1Ile105Val polymorphism on outcome and toxicity in 140 patients with advanced Hodgkin's lymphoma enrolled in the prospective multicenter HD2000-GISL trial, comparing ABVD, BEACOPP and CEC regimens. Carriers of the GSTP1Ile105Val polymorphism had a higher rate of grade 3-4 anemia following treatment. Overall, our study failed to validate GST genotyping as prognostic factor for progression-free survival (PFS). Only the small cohort of patients with an international prognostic score (IPS) >3 and undeleted GSTT1 and/or GSTM1, treated with ABVD had worse progression-free survival (PFS) (GSTT1 + vs GSTT1-: HR 5.02, 95% C.I., 1.16-21.8, p = 0.031, GSTM1 + /GSTT1 + vs GSTM1-and/or GSTT1-: HR 4.61, 95% C.I. 1.28- 16.6, p = 0.019, respectively). No differences were observed for patients treated with intensified regimens, as BEACOPP and CEC. In conclusion, the prognostic role of GST polymorphism, if at all, is limited to a small subgroup of patients treated with standard ABVD regimen.