The Hairy Cell Leukemia Consortium was founded in 2008 to address researchers' concerns about the long-term future of research on the disease. Partly because existing treatments are so successful, the field has attracted very few new researchers.

In 2013 the Hairy Cell Leukemia Foundation was created when the Hairy Cell Leukemia Consortium and the Hairy Cell Leukemia Research Foundation joined together. The HCLF is dedicated to improving outcomes for patients by advancing research into the causes and treatment of hairy cell leukemia, as well as by providing educational resources and comfort to all those affected by hairy cell leukemia.

Three immunotoxin drugs have been studied in patients at the NIHNational Cancer Institute in the U.S.: BL22, HA22 and LMB-2. All of these protein-based drugs combine part of an anti-B cell antibody with a bacterial toxin to kill the cells on internalization. BL22 and HA22 attack a common protein called CD22, which is present on hairy cells and healthy B cells. LMB-2 attacks a protein called CD25, which is not present in HCL-variant, so LMB-2 is only useful for patients with HCL-classic or the Japanese variant. HA-22, now renamed moxetumab pasudotox, is being studied in patients with relapsed hairy cell leukemia at the National Cancer Institute in Bethesda, Maryland, MD Anderson Cancer Center in Houston, Texas, and Ohio State University in Columbus, Ohio. Other sites for the study are expected to start accepting patients in late 2014, including The Royal Marsden Hospital in London, England.

Other clinical trials are studying the effectiveness of cladribine followed by rituximab in eliminating residual hairy cells that remain after treatment by cladribine or pentostatin. It is not currently known if the elimination of such residual cells will result in more durable remissions.

BRAF mutation has been frequently detected in HCL (Tiacci et al. NEJM 2011) and some patients may respond to Vemurafenib

The major remaining research questions are identifying the cause of HCL and determining what prevents hairy cells from maturing normally.

Immunoglobulin E (IgE) is important in mast cell function. Immunotherapy with anti-IgE immunoglobulin raised in sheep resulted in a transient decrease in the numbers of circulating mast cells in one patient with mast cell leukemia. Although splenectomy has led to brief responses in patients with mast cell leukemia, no firm conclusions as to the efficacy of this treatment are possible. Chemotherapy with combination of cytosine arabinoside and either idarubicin, daunomycin, or mitoxantrone as for acute myeloid leukemia has been used. Stem cell transplantation is an option, although no experience exists concerning responses and outcome.

Pralatrexate is one compound currently under investigations for the treatment of PTCL.

Leukemia is rarely associated with pregnancy, affecting only about 1 in 10,000 pregnant women. How it is handled depends primarily on the type of leukemia. Acute leukemias normally require prompt, aggressive treatment, despite significant risks of pregnancy loss and birth defects, especially if chemotherapy is given during the developmentally sensitive first trimester.

Novel approaches to the treatment of PTCL in the relapsed or refractory setting are under investigation. Pralatrexate is one compound currently under investigations for the treatment of PTCL.

Acute mast cell leukemia is extremely aggressive and has a grave prognosis. In most cases, multi-organ failure including bone marrow failure develops over weeks to months. Median survival after diagnosis is only about 6 months.

If a patient is resistant to either cladribine or pentostatin, then second-line therapy is pursued.

Monoclonal antibodies The most common treatment for cladribine-resistant disease is infusing monoclonal antibodies that destroy cancerous B cells. Rituximab is by far the most commonly used. Most patients receive one IV infusion over several hours each week for four to eight weeks. A 2003 publication found two partial and ten complete responses out of 15 patients with relapsed disease, for a total of 80% responding. The median patient (including non-responders) did not require further treatment for more than three years. This eight-dose study had a higher response rate than a four-dose study at Scripps, which achieved only 25% response rate. Rituximab has successfully induced a complete response in Hairy Cell-Variant.

Rituximab's major side effect is serum sickness, commonly described as an "allergic reaction", which can be severe, especially on the first infusion. Serum sickness is primarily caused by the antibodies clumping during infusion and triggering the complement cascade. Although most patients find that side effects are adequately controlled by anti-allergy drugs, some severe, and even fatal, reactions have occurred. Consequently, the first dose is always given in a hospital setting, although subsequent infusions may be given in a physician's office. Remissions are usually shorter than with the preferred first-line drugs, but hematologic remissions of several years' duration are not uncommon.

Other B cell-destroying monoclonal antibodies such as Alemtuzumab, Ibritumomab tiuxetan and I-131 Tositumomab may be considered for refractory cases.

Interferon-alpha Interferon-alpha is an immune system hormone that is very helpful to a relatively small number of patients, and somewhat helpful to most patients. In about 65% of patients, the drug helps stabilize the disease or produce a slow, minor improvement for a partial response.

The typical dosing schedule injects at least 3 million units of Interferon-alpha (not pegylated versions) three times a week, although the original protocol began with six months of daily injections.

Some patients tolerate IFN-alpha very well after the first couple of weeks, while others find that its characteristic flu-like symptoms persist. About 10% of patients develop a level of depression. It is possible that, by maintaining a steadier level of the hormone in the body, that daily injections might cause fewer side effects in selected patients. Drinking at least two liters of water each day, while avoiding caffeine and alcohol, can reduce many of the side effects.

A drop in blood counts is usually seen during the first one to two months of treatment. Most patients find that their blood counts get worse for a few weeks immediately after starting treatment, although some patients find their blood counts begin to improve within just two weeks.

It typically takes six months to figure out whether this therapy is useful. Common criteria for treatment success include:

- normalization of hemoglobin levels (above 12.0 g/dL),

- a normal or somewhat low platelet count (above 100 K/µL), and

- a normal or somewhat low absolute neutrophil count (above 1.5 K/µL).

If it is well tolerated, patients usually take the hormone for 12 to 18 months. An attempt may be made then to end the treatment, but most patients discover that they need to continue taking the drug for it to be successful. These patients often continue taking this drug indefinitely, until either the disease becomes resistant to this hormone, or the body produces an immune system response that limits the drug's ability to function. A few patients are able to achieve a sustained clinical remission after taking this drug for six months to one year. This may be more likely when IFN-alpha has been initiated shortly after another therapy. Interferon-alpha is considered the drug of choice for pregnant women with active HCL, although it carries some risks, such as the potential for decreased blood flow to the placenta.

Interferon-alpha works by sensitizing the hairy cells to the killing effect of the immune system hormone TNF-alpha, whose production it promotes. IFN-alpha works best on classic hairy cells that are not protectively adhered to vitronectin or fibronectin, which suggests that patients who encounter less fibrous tissue in their bone marrow biopsies may be more likely to respond to Interferon-alpha therapy. It also explains why non-adhered hairy cells, such as those in the bloodstream, disappear during IFN-alpha treatment well before reductions are seen in adhered hairy cells, such as those in the bone marrow and spleen.

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.

The 5 year survival has been noted as 89% in at least one study from France of 201 patients with T-LGL leukemia.

AML-M5 is treated with intensive chemotherapy (such as anthracyclines) or with bone marrow transplantation.

Currently Aggressive NK-cell leukemia, being a subtype of PTCL, is treated similarly to B-cell lymphomas. However, in recent years, scientists have developed techniques to better recognize the different types of lymphomas, such as PTCL. It is now understood that PTCL behaves differently from B-cell lymphomas and therapies are being developed that specifically target these types of lymphoma. Currently, however, there are no therapies approved by the U.S. Food and Drug Administration (FDA) specifically for PTCL. Anthracycline-containing chemotherapy regimens are commonly offered as the initial therapy. Some patients may receive a stem cell transplant. Novel approaches to the treatment of PTCL in the relapsed or refractory setting are under investigation.

Most patients with T-cell prolymphocytic leukemia require immediate treatment.

T-cell prolymphocytic leukemia is difficult to treat, and it does not respond to most available chemotherapeutic drugs. Many different treatments have been attempted, with limited success in certain patients: purine analogues (pentostatin, fludarabine, cladribine), chlorambucil, and various forms of combination chemotherapy regimens, including cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP), etoposide, bleomycin (VAPEC-B).

Alemtuzumab (Campath), an anti-CD52 monoclonal antibody that attacks white blood cells, has been used in treatment with greater success than previous options. In one study of previously treated people with T-PLL, people who had a complete response to alemtuzumab survived a median of 16 months after treatment.

Some patients who successfully respond to treatment also undergo stem cell transplantation to consolidate the response.

Alemtuzumab has been investigated for use in treatment of refractory T-cell large granular lymphocytic leukemia.

T-PLL is an extremely rare aggressive disease, and patients are not expected to live normal lifespans. Before the recent introduction of better treatments, such as alemtuzumab, the median survival time was 7.5 months after diagnosis. More recently, some patients have survived five years and more, although the median survival is still low.

ANKL is treated similarly to most B-cell lymphomas. Anthracycline-containing chemotherapy regimens are commonly offered as the initial therapy. Some patients may receive a stem cell transplant.

Most patients will die 2 years after diagnosis.

Leukemia is rarely associated with pregnancy, affecting only about 1 in 10,000 pregnant women. The management of leukemia in a pregnant patient depends primarily on the type of leukemia. Acute leukemias normally require prompt, aggressive treatment, despite significant risks of pregnancy loss and birth defects, especially if chemotherapy is given during the developmentally sensitive first trimester.

Research in 2008 is comparing different forms of bone marrow transplants to determine which patients are the best candidates and which approach is best in different situations.

Researchers at the Abramson Cancer Center of the University of Pennsylvania School of Medicine reported preliminary success in the use of gene therapy, through genetically modified T cells, to treat CLL. The findings, which were published in August 2011, were based on data from three patients who had modified T cells injected into their blood. The T cells had been modified to express genes that would allow the cells to proliferate in the body and destroy B cells including those causing the leukemia. Two patients went into remission, while the presence of leukemia in the third patient reduced by 70%. One of the patients had been diagnosed with CLL for 13 years, and his treatment was failing before he participated in the clinical trial. One week after the T cells were injected, the leukemia cells in his blood had disappeared. The T cells were still found in the bloodstream of the patients six months after the procedure, meaning they would be able to fight the disease should leukemia cells return. This was the first time scientists "have used gene therapy to successfully destroy cancer tumors in patients with advanced disease".

Research is also investigating therapies targeting B cell receptor signalling. Syk inhibitor fostamatinib is in trials.

Leukemia is rarely associated with pregnancy, affecting only about 1 in 10,000 pregnant women. How it is handled depends primarily on the type of leukemia. Nearly all leukemias appearing in pregnant women are acute leukemias. Acute leukemias normally require prompt, aggressive treatment, despite significant risks of pregnancy loss and birth defects, especially if chemotherapy is given during the developmentally sensitive first trimester. Chronic myelogenous leukemia can be treated with relative safety at any time during pregnancy with Interferon-alpha hormones. Treatment for chronic lymphocytic leukemias, which are rare in pregnant women, can often be postponed until after the end of the pregnancy.

As the end stage of multiple myeloma that has failed or broken through one or more therapeutic regimens, sPCL continues to be highly refractory to various treatment regimens (<50%), very short response times of these regiments, and poor overall survival rates (median survival of 2-8 to months). Patients with sPCL may have short-lived responses to treatment regimens (as communicated in case reports) that include bortezomid but there are no established therapeutic regimens that have clearly been shown to improve their overall or median survival.

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 the recurrent leukemia will respond favorably to the standard chemotherapy regimen that was initially implemented, and instead these patients should be trialed on reinduction chemotherapy followed by allogeniec bone marrow transplantation. These patients 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.

Recently, there has also been evidence and approval of use for dasatinib, a tyrosine kinase inhibitor. It has shown efficacy in cases of patients with Ph1-positive and imatinib-resistant ALL, but more research needs to be done on long term survival and time to relapse.

Recent case report studies suggest that treatment regimens which include a proteasome inhibitor drug, particularly bortezomib, and/or autologous stem-cell transplantation have improved pPCL survival. For example, 28 patients treated with a bortezomib-based induction regimen followed by autologous stem-cell transplantation and then a maintenance regimen of lenaldomide (an immunosuppressant related to thalidomide), bortezomib, and dexamethasone (a corticosteroid) has a progression free survival rate of 66% at 3 years and an overall survival rate of 73% at 4 years. In one study, patients receiving intensive chemotherapy plus autologous stem-cell transplantation had a median survival of 34 months while those receiving chemotherapy alone had a median survival of 11 months. Two other studies that included bortezomib in their chemotherapy regimens likewise found that the addition of autologous stem-cell transplantation improved results. Current recommendations for treating pPCL often include induction with a three drug regimen such as borezomib-lenalidomide-dexamethasone followed by autologous stem-cell transplantion and consolidation/maintenance with of combination of immunomodulator agents (e.g. thalidomide, lenalidomide, or pomalidomide) plus a proteasome inhibitor (bortezomib, ixazomib, or carfilzomib.

In the past 5 years, the research for the mechanisms of BAL does not have a great progress. Some new translocate case of BAL has been reported, such as t(15,17) and t(12,13). For t(15;17), the blasts with morphology of acute lymphoblastic leukemia co-expressed in B-lymphoid and myeloid lineages, and the cytogenetic study showed that the 4q21 abnormalities and t(15;17). However, promyelocytic-retinoid acid receptor rearrangement was not found by fluorescence in situ hybridization on interphase nuclei. Researchers also found some new chemotherapy method for specific cases. For example, The chemotherapy for ALL and gemtuzuab ozogamicin without all-trans-retinoic acid remain complete remission of the BAL patients with t(15,17) for more than 3.7 years.

The detection of BCR-ABL1 chimeric gene neutrophils was also found a good method for diagnosis some cases of BAL.

Totally, there is no breakthrough research for the therapy or mechanisms of BAL in recent years. For most of BAL patients, there is no good therapy method because we still don’t fully understand the mechanisms of BAL. Thus, we have to learn more about the different cases, do more research on the mutation that lead BAL. Beside chemotherapy, we should develop new method such as gene drug for BAL therapy.

If a patient has the symptoms like leukemia, such as persistent fever or difficulty of hemostais, he has to see the doctors.

BAL is very hard to treat. Most of patients receive treatment based on the morphology of blasts and get AML or ALL induction chemotherapy. The induction drug for AML such as cytarabine and anthracycline, drug for ALL such as prednisolone, dexamethasone, vincristine, asparaginase or daunorubicin is common for BAL remission induction therapy. Recently, researches showed that using both myeloid and lymphoid induction therapy may be better for prognosis.

Chemotherapy is strong side effects such as typhlitis, gastrointestinal distress, anemia, fatigue, hair loss, nausea and vomiting, etc. Thus, the different dose and times of chemotherapy for different individuals is important.

If the patients enter fully remission, the consolidation with stem cell transplantation is highly recommended.

The treatment a child will undergo is based on the child's age, overall health, medical history, their tolerance for certain medications, procedures, and therapies, along with the parents' opinion and preference.

- Chemotherapy is a treatment that uses drugs to interfere with the cancer cells ability to grow and reproduce. Chemotherapy can be used alone or in combination with other therapies. Chemotherapy can be given either as a pill to swallow orally, an injection into the fat or muscle, through an IV directly into the bloodstream, or directly into the spinal column.

- A stem cell transplant is a process by which healthy cells are infused into the body. A stem-cell transplant can help the human body make enough healthy white blood cells, red blood cells, or platelets, and reduce the risk of life-threatening infections, anemia, and bleeding. It is also known as a bone-marrow transplant or an umbilical-cord blood transplant, depending on the source of the stem cells. Stem cell transplants can use the cells from the same person, called an autologous stem cell transplant or they can use stem cells from other people, known as an allogenic stem cell transplant. In some cases, the parents of a child with childhood leukemia may conceive a saviour sibling by preimplantation genetic diagnosis to be an appropriate match for the HLA antigen.

JMML accounts for 1-2% of childhood leukemias each year; in the United States, an estimated 25-50 new cases are diagnosed each year, which also equates to about 3 cases per million children. There is no known environmental cause for JMML. Since about 10% of patients are diagnosed before 3 months of age, it is thought that JMML is a congenital condition in these infants