T-cell acute lymphoblastic lymphoma (T-LBL) is an aggressive neoplasm that arises in children, adolescents and adults and is thought to be related to T-cell acute lymphoblastic leukemia (T-ALL). According to the WHO guidelines the term T-LBL is used when bone marrow infiltration by tumor cells is limited (<25%) all other cases are regarded as T-ALL. It is not clear whether T-ALL and TLBL chemotherapy which is associated with often debilitating toxicities. Further advances in the treatment of this malignancy require the development of effective targeted drugs. PIM1 is a constitutively active kinase that is overexpressed in a large number of cancer subtypes. Several PIM inhibitors are currently tested in clinical trials for the treatment of different malignancies. Recently, we identified a novel translocation that causes aberrant overexpression of PIM1 in a T-LBL case, suggesting a role for PIM1 in T-LBL.