Acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL), also known as acute lymphocytic leukemia or acute lymphoid leukemia, is a cancer of the blood and bone marrow characterized by the uncontrolled proliferation of immature lymphoid cells (lymphoblasts). These abnormal cells accumulate in the bone marrow, crowding out normal blood cell production, and can spread to the blood, lymph nodes, spleen, liver, central nervous system, and other organs. ALL is the most common childhood cancer, though it also occurs in adults. The disease is classified into B-cell ALL (approximately 85% of pediatric cases) and T-cell ALL based on the lineage of the affected lymphoblasts. Key symptoms result from bone marrow failure and organ infiltration. Patients typically present with fatigue, pallor, and weakness due to anemia; recurrent or severe infections due to neutropenia; and easy bruising, petechiae, or bleeding due to thrombocytopenia. Other common features include bone and joint pain, fever, lymphadenopathy (swollen lymph nodes), hepatosplenomegaly (enlarged liver and spleen), and unexplained weight loss. Central nervous system involvement may cause headaches, vomiting, or cranial nerve palsies. The treatment landscape for ALL has evolved significantly, particularly in pediatric patients where cure rates now exceed 85-90%. Treatment typically involves multi-agent chemotherapy administered in phases: induction (to achieve remission), consolidation/intensification (to eliminate residual disease), and maintenance therapy, often spanning two to three years. CNS-directed therapy (intrathecal chemotherapy and/or cranial radiation) is a critical component. For relapsed or refractory disease, options include targeted therapies such as tyrosine kinase inhibitors for Philadelphia chromosome-positive ALL, bispecific T-cell engager antibodies (blinatumomab), antibody-drug conjugates (inotuzumab ozogamicin), and chimeric antigen receptor (CAR) T-cell therapy. Allogeneic hematopoietic stem cell transplantation remains an important option for high-risk or relapsed patients. Adult ALL carries a less favorable prognosis than pediatric ALL, though outcomes have improved with the adoption of pediatric-inspired treatment protocols.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Acute lymphoblastic leukemia