Updates in biology, classification, and management of acute myeloid leukemia with antecedent hematologic disorder and therapy related acute myeloid leukemia.

Acute myeloid leukemia with antecedent hematologic disorder (AHD-AML) and therapy related AML (t-AML) constitute a heterogenous disease with inferior outcomes. It is often characterized by high-risk cytogenetic and molecular alterations associated with AHD or prior cancer therapy. Historically, the standard of care treatment has been intensive induction with "7 + 3", with an improved overall response rate and survival with CPX-351. Results from large registry-based studies suggested that allogeneic hematopoietic stem cell transplant is preferable to consolidation chemotherapy alone for achieving long-term survival in patients with AHD-AML. Prevalence of high-risk genetic features and advanced age and comorbidities in patients make AHD-AML and t-AML clinically challenging subgroups to treat with intensive approaches. Recent reports on less intensive treatment options, particularly the hypomethylating agent-venetoclax combination, have shown encouraging response rates in these patients. However, emerging resistance mechanisms compromise duration of response and overall survival. Several novel agents targeting apoptotic machinery, signaling pathways, and immune checkpoints are under clinical investigation, with an aim to truly improve overall outcomes in this subgroup. We reviewed updates in biology, classification, and clinical data comparing safety and efficacy of intensive and less intensive treatment options, and summarized ongoing studies with promising novel therapies in AHD-AML and t-AML.

A rare case of Philadelphia-positive (P210BCR-ABL1) T-cell acute lymphoblastic leukemia/lymphoma associated with minimal residual disease persistence after intensive chemotherapeutic approaches.

T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) is a rare and aggressive leukemia. Philadelphia chromosome-positive cytogenetic abnormality is most common in CML. It is difficult to differentiate between de novo Ph+ T-ALL/LBL and T-cell lymphoblastic crises of CML. We present a case of adult Ph+ T-ALL/LBL with a likely history of antecedent CML. Initially thought to be a case of chronic-phase CML, a diagnostic quandary led to the pursuit of a lymph node biopsy that established the diagnosis of Ph+ T-LBL or T lymphoblastic blast crisis of CML, a clinical presentation extremely rare and only the second of its kind from our review of the literature. The patient was treated with an intensive chemotherapy regimen for over a year due to persistent minimal residual disease (MRD) positivity indicating aggressive disease.