Many different anti-cancer drugs are effective for the treatment of AML. Treatments vary somewhat according to the age of the patient and according to the specific subtype of AML. Overall, the strategy is to control bone marrow and systemic (whole-body) disease, while offering specific treatment for the central nervous system (CNS), if involved.

In general, most oncologists rely on combinations of drugs for the initial, "induction phase" of chemotherapy. Such combination chemotherapy usually offers the benefits of early remission and a lower risk of disease resistance. "Consolidation" and "maintenance" treatments are intended to prevent disease recurrence. Consolidation treatment often entails a repetition of induction chemotherapy or the intensification chemotherapy with additional drugs. By contrast, maintenance treatment involves drug doses that are lower than those administered during the induction phase.

Targeted therapy attacks cancer cells at a specific target, with the aim of not harming normal cells.

- Alemtuzumab is a mAb directed against CD52 used in CLL.

- Rituximab, ofatumumab, and obinutuzumab are antibodies against CD20 used to treat CLL.

- Ibrutinib, a Bruton's tyrosine kinase (BTK) inhibitor, is used to treat CLL.

- Idelalisib is a PI3K inhibitor. and is taken orally.

- Venetoclax is a Bcl-2 inhibitor used to treat people with CLL who have 17p deletion (deletion located on the chromosome 17 short arm) and who have been treated with at least one prior therapy.

For most people with CLL, it is incurable by present treatments, so treatment is directed towards suppressing the disease for many years, rather than totally and permanently eliminating it. The primary chemotherapeutic plan is combination chemotherapy with chlorambucil or cyclophosphamide, plus a corticosteroid such as prednisone or prednisolone. The use of a corticosteroid has the additional benefit of suppressing some related autoimmune diseases, such as immunohemolytic anemia or immune-mediated thrombocytopenia. In resistant cases, single-agent treatments with nucleoside drugs such as fludarabine, pentostatin, or cladribine may be successful. Younger and healthier patients may choose allogeneic or autologous bone marrow transplantation in the hope of a permanent cure.

Combination chemotherapy regimens are effective in both newly diagnosed and relapsed CLL. Combinations of fludarabine with alkylating agents (cyclophosphamide) produce higher response rates and a longer progression-free survival than single agents:

- FC (fludarabine with cyclophosphamide)

- FR (fludarabine with rituximab)

- FCR (fludarabine, cyclophosphamide, and rituximab)

- CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone)

Although the purine analogue fludarabine was shown to give superior response rates to chlorambucil as primary therapy, no evidence shows early use of fludarabine improves overall survival, and some clinicians prefer to reserve fludarabine for relapsed disease.

Chemoimmunotherapy with FCR has shown to improve response rates, progression-free survival, and overall survival in a large randomized trial in CLL patients selected for good physical fitness. This has been the first clinical trial demonstrating that the choice of a first-line therapy can improve the overall survival of patients with CLL.

Alkylating agents approved for CLL include bendamustine and cyclophosphamide.

Selection of biological targets on the basis of their combinatorial effects on the leukemic lymphoblasts can lead to clinical trials for improvement in the effects of ALL treatment. Tyrosine-kinase inhibitors (TKIs), such as Imatinib, are often incorporated into the treatment plan for patients with "Bcr-Abl1+ (Ph+)" ALL. However, this subtype of ALL is frequently resistant to the combination of chemotherapy and TKIs and allogeneic stem cell transplantation is often recommended upon relapse.

Blinatumomab, a CD19-CD3 bi-specific monoclonal murine antibody, currently shows promise as a novel pharmacotherapy. By engaging the CD3 T-cell with the CD19 receptor on B cells, it triggers a response to induce the release of inflammatory cytokines, cytotoxic proteins and proliferation of T cells to kill CD19 B cells.

Radiation therapy (or radiotherapy) is used on painful bony areas, in high disease burdens, or as part of the preparations for a bone marrow transplant (total body irradiation). In the past, physicians commonly utilized radiation in the form of whole-brain radiation for central nervous system prophylaxis, to prevent occurrence and/or recurrence of leukemia in the brain. Recent studies showed that CNS chemotherapy provided results as favorable but with less developmental side-effects. As a result, the use of whole-brain radiation has been more limited. Most specialists in adult leukemia have abandoned the use of radiation therapy for CNS prophylaxis, instead using intrathecal chemotherapy.

First-line treatment of AML consists primarily of chemotherapy, and is divided into two phases: induction and postremission (or consolidation) therapy. The goal of induction therapy is to achieve a complete remission by reducing the number of leukemic cells to an undetectable level; the goal of consolidation therapy is to eliminate any residual undetectable disease and achieve a cure. Hematopoietic stem cell transplantation is usually considered if induction chemotherapy fails or after a person relapses, although transplantation is also sometimes used as front-line therapy for people with high-risk disease. Efforts to use tyrosine kinase inhibitors in AML continue.

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.

After stable remission is induced, the standard of care is to undergo 2 years of maintenance chemotherapy with methotrexate, mercaptopurine and ATRA. A significant portion of patients will relapse without consolidation therapy. In the 2000 European APL study, the 2-year relapse rate for those that did not receive consolidation chemotherapy (ATRA not included) therapy was 27% compared to 11% in those that did receive consolidation therapy (p<0.01). Likewise in the 2000 US APL study, the survival rates in those receiving ATRA maintenance was 61% compared to just 36% without ATRA maintenance.

Arsenic trioxide (AsO) is currently being evaluated for treatment of relapsed / refractory disease. Remission with arsenic trioxide has been reported.

Studies have shown arsenic reorganizes nuclear bodies and degrades the mutant PML-RAR fusion protein. Arsenic also increases caspase activity which then induces apoptosis. It does reduce the relapse rate for high risk patients. In Japan a synthetic retinoid, tamibarotene, is licensed for use as a treatment for ATRA-resistant APL.

All FAB subtypes except M3 are usually given induction chemotherapy with cytarabine (ara-C) and an anthracycline (most often daunorubicin). This induction chemotherapy regimen is known as "7+3" (or "3+7"), because the cytarabine is given as a continuous IV infusion for seven consecutive days while the anthracycline is given for three consecutive days as an IV push. Up to 70% of people with AML will achieve a remission with this protocol. Other alternative induction regimens, including high-dose cytarabine alone, FLAG-like regimens or investigational agents, may also be used. Because of the toxic effects of therapy, including myelosuppression and an increased risk of infection, induction chemotherapy may not be offered to the very elderly, and the options may include less intense chemotherapy or palliative care.

The M3 subtype of AML, also known as acute promyelocytic leukemia (APL), is almost universally treated with the drug all-"trans"-retinoic acid (ATRA) in addition to induction chemotherapy, usually an anthracycline. Care must be taken to prevent disseminated intravascular coagulation (DIC), complicating the treatment of APL when the promyelocytes release the contents of their granules into the peripheral circulation. APL is eminently curable, with well-documented treatment protocols.

The goal of the induction phase is to reach a complete remission. Complete remission does not mean the disease has been cured; rather, it signifies no disease can be detected with available diagnostic methods. Complete remission is obtained in about 50%–75% of newly diagnosed adults, although this may vary based on the prognostic factors described above. The length of remission depends on the prognostic features of the original leukemia. In general, all remissions will fail without additional consolidation 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.

Several treatments are available, and successful control of the disease is common.

Not everyone needs treatment immediately. Treatment is usually given when the symptoms of the disease interfere with the patient's everyday life, or when white blood cell or platelet counts decline to dangerously low levels, such as an absolute neutrophil count below one thousand cells per microliter (1.0 K/uL). Not all patients need treatment immediately upon diagnosis.

Treatment delays are less important than in solid tumors. Unlike most cancers, treatment success does not depend on treating the disease at an early stage. Because delays do not affect treatment success, there are no standards for how quickly a patient should receive treatment. However, waiting too long can cause its own problems, such as an infection that might have been avoided by proper treatment to restore immune system function. Also, having a higher number of hairy cells at the time of treatment can make certain side effects somewhat worse, as some side effects are primarily caused by the body's natural response to the dying hairy cells. This can result in the hospitalization of a patient whose treatment would otherwise be carried out entirely at the hematologist's office.

Single-drug treatment is typical. Unlike most cancers, only one drug is normally given to a patient at a time. While monotherapy is normal, combination therapy—typically using one first-line therapy and one second-line therapy—is being studied in current clinical trials and is used more frequently for refractory cases. Combining rituximab with cladribine or pentostatin may or may not produce any practical benefit to the patient. Combination therapy is almost never used with a new patient. Because the success rates with purine analog monotherapy are already so high, the additional benefit from immediate treatment with a second drug in a treatment-naïve patient is assumed to be very low. For example, one round of either cladribine or pentostatin gives the median first-time patient a decade-long remission; the addition of rituximab, which gives the median patient only three or four years, might provide no additional value for this easily treated patient. In a more difficult case, however, the benefit from the first drug may be substantially reduced and therefore a combination may provide some benefit.

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.

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.

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.

Treatment can occasionally consist of "watchful waiting" (e.g. in CLL) or symptomatic treatment (e.g. blood transfusions in MDS). The more aggressive forms of disease require treatment with chemotherapy, radiotherapy, immunotherapy and—in some cases—a bone marrow transplant. The use of rituximab has been established for the treatment of B-cell–derived hematologic malignancies, including follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL).

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

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.

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.

As described above, chloromas should always be considered manifestations of systemic disease, rather than isolated local phenomena, and treated as such. In the patient with newly diagnosed leukemia and an associated chloroma, systemic chemotherapy against the leukemia is typically used as the first-line treatment, unless an indication for local treatment of the chloroma (e.g. compromise of the spinal cord) emerges. Chloromas are typically quite sensitive to standard antileukemic chemotherapy. Allogeneic hematopoietic stem cell transplantation should be considered in fit patients with suitable available donor, as long term remissions have been reported.

If the chloroma is persistent after completion of induction chemotherapy, local treatment, such as surgery or radiation therapy, may be considered, although neither has an effect on survival.

Patients presenting with a primary chloroma typically receive systemic chemotherapy, as development of acute leukemia is nearly universal in the short term after detection of the chloroma.

Patients treated for acute leukemia who relapse with an isolated chloroma are typically treated with systemic therapy for relapsed leukemia. However, as with any relapsed leukemia, outcomes are unfortunately poor.

Patients with "preleukemic" conditions, such as myelodysplastic syndromes or myeloproliferative syndromes, who develop a chloroma are often treated as if they have transformed to acute leukemia.

If treatment has been successful ("complete" or "partial remission"), a person is generally followed up at regular intervals to detect recurrence and monitor for "secondary malignancy" (an uncommon side-effect of some chemotherapy and radiotherapy regimens—the appearance of another form of cancer). In the follow-up, which should be done at pre-determined regular intervals, general anamnesis is combined with complete blood count and determination of lactate dehydrogenase or thymidine kinase in serum.

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.

When primary or secondary resistance invariably develops, salvage therapy is considered. Allogeneic stem cell transplantation can induce durable remissions for heavily pre-treated patients.

Should treatment be started it should address both the paraprotein level and the lymphocytic B-cells.

In 2002, a panel at the International Workshop on Waldenström's Macroglobulinemia agreed on criteria for the initiation of therapy. They recommended starting therapy in patients with constitutional symptoms such as recurrent fever, night sweats, fatigue due to anemia, weight loss, progressive symptomatic lymphadenopathy or spleen enlargement, and anemia due to bone marrow infiltration. Complications such as hyperviscosity syndrome, symptomatic sensorimotor peripheral neuropathy, systemic amyloidosis, kidney failure, or symptomatic cryoglobulinemia were also suggested as indications for therapy.

Treatment includes the monoclonal antibody rituximab, sometimes in combination with chemotherapeutic drugs such as chlorambucil, cyclophosphamide, or vincristine or with thalidomide. Corticosteroids, such as prednisone, may also be used in combination. Plasmapheresis can be used to treat the hyperviscosity syndrome by removing the paraprotein from the blood, although it does not address the underlying disease. Ibrutinib is another agent that has been approved for use in this condition.

Recently, autologous bone marrow transplantation has been added to the available treatment options.