Typically this process is done in conjunction with a conditioning regimen such as cyclophosphamide, which has been shown to potentiate the effects of infused T-cells. This effect has been attributed to making an immunologic space within which the cells populate. The process as a whole result in an effector cell, typically a T-cell, that can recognize a tumor cell antigen in a manner that is independent of the major histocompatibility complex and which can initiate a cytotoxic response. In 2017, tisagenlecleucel was approved by the FDA as a CAR-T therapy for people with acute B-cell lymphoblastic leukaemia  who did not respond adequately to other treatments or have relapsed. In a 22-day process, the "drug" is customized for each person. T cells purified from each person are modified by a virus that inserts genes that encode a chimaeric antigen receptor into their DNA, one that recognizes leukemia cells. Relapsed ALL
Typically, people who experience a relapse in their ALL after initial treatment have a poorer prognosis than those who remain in complete remission after induction therapy. It is unlikely that recurrent leukemia will respond favorably to the standard chemotherapy regimen that was initially implemented, and instead, these people should be trialed on reinduction chemotherapy followed by allogeneic bone marrow transplantation. These people in relapse may also receive blinatumomab, as it has shown to increase remission rates and overall survival rates, without increased toxic effects.Low dose palliative radiation may also help reduce the burden of tumor inside or outside the central nervous system and alleviate some symptoms.
This system recognized differences in genetic, immunophenotype, molecular, and morphological features found through cytogenetic and molecular diagnostics tests. : 1531–1535  This subtyping helps determine the prognosis and the most appropriate treatment for each specific case of ALL. The WHO subtypes related to ALL are:
B-lymphoblastic leukemia/lymphoma
Not otherwise specified (NOS)
with recurrent genetic abnormalities
with t(9;22)(q34.1;q11.2);BCR-ABL1
with t(v;11q23.3);KMT2A rearranged
with t(12;21)(p13.2;q22.1); ETV6-RUNX1
with t(5;14)(q31.1;q32.3) IL3-IGH
with t(1;19)(q23;p13.3);TCF3-PBX1
with hyperdiploidy
with hypodiploidy
T-lymphoblastic leukemia/lymphoma
Acute leukemias of ambiguous lineage
Acute undifferentiated leukemia
Mixed phenotype acute leukemia (MPAL) with t(9;22)(q34.1;q11.2); BCR–ABL1
MPAL with t(v;11q23.3); KMT2A rearranged
MPAL, B/myeloid, NOS
MPAL, T/myeloid, NOS

MicroRNA signature
A systematic review of miRNA levels in pediatric B-ALL compared with controls revealed that miR-155 is the most frequently reported upregulated miRNA (followed by miR-146a, miR-181b, miR-222 and miR-708; two citations for miR-16, miR-21, miR-34a, miR-100, miR-128-1, miR-181a, miR-181c, miR-195, miR-210, miR-320a and miR-660), whereas the most frequently reported downregulated miRNA is miR-374a (two citations for miR-27a, miR-30c, miR-196b, miR-223 and miR-494). To date, there is no consensus miRNA signature and this is mainly attributed to different miRNA signatures across ALL subtypes and methodology of conducted studies. Treatment
The aim of treatment is to induce a lasting remission, defined as the absence of detectable cancer cells in the body (usually less than 5% blast cells in the bone marrow). Over the past several decades, there have been strides to increase the efficacy of treatment regimens, resulting in increased survival rates. Possible treatments for acute leukemia include chemotherapy, steroids, radiation therapy, intensive combined treatments (including bone marrow or stem cell transplants), targeted therapy, and/or growth factors.