Transient grades 3 to 4 acute hepatitis is a common complication of rabbit antithymocyte globulin (thymoglobulin) administered before allogeneic stem cell transplantation.

Because antithymocyte globulin (ATG) is increasingly used to prevent graft-versus-host disease (GVHD), we performed a retrospective study in adult patients transplanted at our center between January 2008 and December 2012 to explore incidence, characteristics, potential risk factors, and consequences of severe acute hepatotoxicity (SAH) of rabbit ATG (Thymoglobulin) defined as a grade 3 to 4 increase of transaminases. Two hundred twelve patients were included. SAH was diagnosed in 55 patients, representing an incidence of 26%. SAH occurred at a median time of 2 days (range, 1 to 3) after ATG administration, reaching maximum median levels of aspartate aminotransferase and alanine aminotransferase of 8.7 × upper limit of normal (ULN; range, 1.2 to 160) and 11.7 × ULN (range, 4-100), respectively. The International Normalized Ratio was beyond the normal range in 44% of patients. Transaminases decreased below 2 × ULN after a median time of 9 days. We do not report any deleterious impact of SAH on survival, nonrelapse mortality, relapse, or GVHD. Blood systolic pressure < 90 mm Hg during administration of ATG and 2 previous autologous SCT were identified as risk factors for SAH. We believe physicians should be aware of this common toxicity immediately after the administration of ATG to avoid any potential hepatotoxic drug before the resolution and to prevent any risk of hemorrhagic accident.

Genomic analysis of primary and secondary myelofibrosis redefines the prognostic impact of ASXL1 mutations: a FIM study.

We aimed to study the prognostic impact of the mutational landscape in primary and secondary myelofibrosis. The study included 479 patients with myelofibrosis recruited from 24 French Intergroup of Myeloproliferative Neoplasms (FIM) centers. The molecular landscape was studied by high-throughput sequencing of 77 genes. A Bayesian network allowed the identification of genomic groups whose prognostic impact was studied in a multistate model considering transitions from the 3 conditions: myelofibrosis, acute leukemia, and death. Results were validated using an independent, previously published cohort (n = 276). Four genomic groups were identified: patients with TP53 mutation; patients with ≥1 mutation in EZH2, CBL, U2AF1, SRSF2, IDH1, IDH2, NRAS, or KRAS (high-risk group); patients with ASXL1-only mutation (ie, no associated mutation in TP53 or high-risk genes); and other patients. A multistate model found that both TP53 and high-risk groups were associated with leukemic transformation (hazard ratios [HRs] [95% confidence interval], 8.68 [3.32-22.73] and 3.24 [1.58-6.64], respectively) and death from myelofibrosis (HRs, 3.03 [1.66-5.56] and 1.77 [1.18-2.67], respectively). ASXL1-only mutations had no prognostic value that was confirmed in the validation cohort. However, ASXL1 mutations conferred a worse prognosis when associated with a mutation in TP53 or high-risk genes. This study provides a new definition of adverse mutations in myelofibrosis with the addition of TP53, CBL, NRAS, KRAS, and U2AF1 to previously described genes. Furthermore, our results argue that ASXL1 mutations alone cannot be considered detrimental.