Lymphoid leukemias are a group of

leukemia Leukemia ( also spelled leukaemia and pronounced ) is a group of blood cancers that usually begin in the bone marrow and result in high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or ...

s affecting circulating

lymphocyte A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic a ...

s, a type of

white blood cell White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...

. The lymphocytic leukemias are closely related to

lymphoma Lymphoma is a group of blood and lymph tumors that develop from lymphocytes (a type of white blood cell). In current usage the name usually refers to just the cancerous versions rather than all such tumours. Signs and symptoms may include en ...

s of the lymphocytes, to the point that some of them are unitary disease entities that can be called by either name (for example, adult T-cell leukemia/lymphoma). Such diseases are all

lymphoproliferative disorders Lymphoproliferative disorders (LPDs) refer to a specific class of diagnoses, comprising a group of several conditions, in which lymphocytes are produced in excessive quantities. These disorders primarily present in patients who have a compromised i ...

. Most lymphoid leukemias involve a particular subtype of lymphocytes, the

B cell B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted o ...

Classification

Historically, they have been most commonly divided by the stage of maturation at which the clonal (neoplastic) lymphoid population stopped maturing: *

Acute lymphoblastic leukemia Acute lymphoblastic leukemia (ALL) is a cancer of the lymphoid line of blood cells characterized by the development of large numbers of immature lymphocytes. Symptoms may include feeling tired, pale skin color, fever, easy bleeding or bruis ...

Chronic lymphocytic leukemia Chronic lymphocytic leukemia (CLL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). Early on, there are typically no symptoms. Later, non-painful lymph node swelling, feeling tired, fever ...

However, the influential WHO Classification (published in 2001) emphasized a greater emphasis on cell lineage. To this end, lymphoid leukemias can also be divided by the type of cells affected: *

B-cell leukemia A B-cell leukemia is any of several types of lymphoid leukemia which affect B cells. Types include (with ICD-O code): * 9823/3 - B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma * 9826/3 - Acute lymphoblastic leukemia, mature B-cell ...

* T-cell leukemia * NK-cell leukemia The most common type of lymphoid leukemia is

B-cell chronic lymphocytic leukemia Chronic lymphocytic leukemia (CLL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). Early on, there are typically no symptoms. Later, non-painful lymph node swelling, feeling tired, fever, nigh ...

B-cell leukemias

B-cell leukemia describes several different types of lymphoid leukemia which affect

s. Other types include (with

ICD-O The International Classification of Diseases for Oncology (ICD-O) is a domain-specific extension of the ICD, International Statistical Classification of Diseases and Related Health Problems for tumor diseases. This classification is widely used by ...

code): * 9826/3 –

, mature B-cell type * 9833/3 – B-cell prolymphocytic leukemia * 9940/3 –

Hairy cell leukemia Hairy cell leukemia is an uncommon hematological malignancy characterized by an accumulation of abnormal B lymphocytes. It is usually classified as a subtype of chronic lymphocytic leukemia (CLL). Hairy cell leukemia makes up about 2% of all leu ...

T-cell leukemias

T-cell leukemia describes several different types of lymphoid leukemias which affect

T cell A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell r ...

s. The most common T-cell leukemia is precursor T-cell lymphoblastic leukemia. It causes 15% of acute leukemias in childhood, and also 40% of lymphomas in childhood. It is most common in adolescent males. Its morphology is identical to that of ''precursor B-cell lymphoblastic leukemia''. Cell markers include TdT,

CD2 CD2 (cluster of differentiation 2) is a cell adhesion molecule found on the surface of T cells and natural killer (NK) cells. It has also been called T-cell surface antigen T11/Leu-5, LFA-2, LFA-3 receptor, erythrocyte receptor and rosette rece ...

, CD7. It often presents as a mediastinal mass because of involvement of the

thymus The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or '' T cells'' mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders ...

. It is highly associated with

NOTCH1 Neurogenic locus notch homolog protein 1 (Notch 1) is a protein encoded in humans by the ''NOTCH1'' gene. Notch 1 is a single-pass transmembrane receptor. Function This gene encodes a member of the Notch family. Members of this Type 1 trans ...

mutations. Other types include: * Large granular lymphocytic leukemia * Adult T-cell leukemia/lymphoma * T-cell prolymphocytic leukemia In practice, it can be hard to distinguish T-cell leukemia from

T-cell lymphoma T-cell lymphoma is a rare form of cancerous lymphoma affecting T-cells. Lymphoma arises mainly from the uncontrolled proliferation of T-cells and can become cancerous. T-cell lymphoma is categorized under Non-Hodgkin lymphoma (NHL) and represents ...

, and they are often grouped together.

NK cell leukemia

Aggressive NK-cell leukemia (ANKL) is a lymphoid leukemia that is a deficiency NK cells. Not very much is known about this disease due to its rarity, but it is highly aggressive. A majority of patients with NK cell leukemia die within a year of diagnosis, and for ANKL in particular, half of patients die within two months.

Diagnosis

The requirements for diagnosing ANKL are as follows: # Immature-looking NK cells # Certain immunophenotypes # Germline configuration genes: TCR-β and IgH # Restricted cytotoxicity The

T-cell receptor The T-cell receptor (TCR) is a protein complex found on the surface of T cells, or T lymphocytes, that is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules. The binding b ...

(TCR) is an important factor when ANKL is being diagnosed along with T-cell leukemia. The TCR gene transcripts are normally positive for ANKL. Current Research is attempting to find the causation of ANKL. So far, the researchers have concluded that lineage of the T-cell receptor gene does not predict the behavior of the disease.

Treatment

ANKL is treated similarly to most

B-cell lymphoma The B-cell lymphomas are types of lymphoma affecting B cells. Lymphomas are "blood cancers" in the lymph nodes. They develop more frequently in older adults and in immunocompromised individuals. B-cell lymphomas include both Hodgkin's lympho ...

Anthracycline Anthracyclines are a class of drugs used in cancer chemotherapy that are extracted from ''Streptomyces'' bacterium. These compounds are used to treat many cancers, including leukemias, lymphomas, breast, stomach, uterine, ovarian, bladder canc ...

-containing

chemotherapy regimens A chemotherapy regimen is a regimen for chemotherapy, defining the drugs to be used, their dosage, the frequency and duration of treatments, and other considerations. In modern oncology, many regimens combine several chemotherapy drugs in combinat ...

are commonly offered as the initial therapy. Some patients may receive a

stem cell transplant Hematopoietic stem-cell transplantation (HSCT) is the transplantation of multipotent hematopoietic stem cells, usually derived from bone marrow, peripheral blood, or umbilical cord blood in order to replicate inside of a patient and to produce ...

. Overall survival depends on the

stage Stage or stages may refer to: Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * Sta ...

of the cancer when treatment is initiated, and on a composite of numerous risk factors. The median time from diagnosis to death is less than 1 year in patients overall. Patients diagnosed early and/or with fewer risk factors can sometimes enter complete remission and expect much longer survival.

Diagnosis

Flow cytometry Flow cytometry (FC) is a technique used to detect and measure physical and chemical characteristics of a population of cells or particles. In this process, a sample containing cells or particles is suspended in a fluid and injected into the flow ...

is a diagnostic tool in order to count/visualize the amount of lymphatic cells in the body. T cells, B cells and NK cells are nearly impossible to distinguish under a microscope, therefore one must use a flow cytometer to distinguish them.

Treatment

Targeted therapy

Several molecular tumor profiling protocols have been initiated in Europe (e.g., MOSCATO-01, iTHER, and ESMART) to identify actionable lesions for targeted treatment in specific subgroups of patients.

NK cell therapy

Natural killer (NK) cell therapy is used in pediatrics for children with relapsed lymphoid leukemia. These patients normally have a resistance to chemotherapy, therefore, in order to continue on, must receive some kind of therapy. In some cases, NK cell therapy is a choice. NK cells are known for their ability to eradicate tumor cells without any prior sensitization to them. One problem when using NK cells in order to fight off lymphoid leukemia is the fact that it is hard to amount enough of them to be effective. One can receive donations of NK cells from parents or relatives through bone marrow transplants. There are also the issues of cost, purity and safety. Unfortunately, there is always the possibility of Graft vs host disease while transplanting bone marrow. NK cell therapy is a possible treatment for many different cancers such as Malignant glioma.

References

External links

{{Lymphoid malignancy Leukemia