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

Currently 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 US 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.

Pralatrexate is one compound currently under investigations for the treatment of PTCL. For information please consult the US clinical trials database (http://www.clinicaltrials.gov).

The typical patient with angioimmunoblastic T-cell lymphoma (AITL) is either middle-aged or elderly, and no gender preference for this disease has been observed. AITL comprises 15–20% of peripheral T-cell lymphomas and 1–2% of all non-Hodgkin lymphomas.

6% of non-Hodgkin lymphoma cases are mantle cell lymphoma. As of 2015, the ratio of males to females affected is about 4:1.

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.

There is no proven or standard first-line chemotherapy that works for the majority of AITL patients. There are several clinical trials that offer treatment options that can fight the disease. Stem cell transplantation is the treatment of choice, with the allogeneic one being the preference because AITL tends to recur after autologous transplants.

CHOP frequently induces remission initially, but most patients relapse and die within two years. Autologous bone marrow transplantation is currently being investigated in the treatment of hepatosplenic lymphoma. Allogeneic bone marrow transplant has been proven to attain remission for over five years and possibly cure hepatosplenic lymphoma.

A second regimen under evaluation is R-EPOCH (rituximab with etoposide-prednisone-vincristine-doxorubicin-cyclophosphamide), which demonstrated a 5-year progression-free survival (PFS) of 79% in a phase II trial. A phase III trial, CALGB 50303, is now comparing R-EPOCH with R-CHOP in patients with newly diagnosed DLBCL.

One area of active research is on separating patients into groups based on their prognosis and how likely they are to benefit from different drugs. Methods like gene expression profiling and next-generation sequencing may result in more effective and more personalized treatment.

Less than 1% of all lymphomas are splenic marginal zone lymphomas and it is postulated that SMZL may represent a large fraction of unclassifiable CD5- chronic lymphocytic leukemias. The typical patient is over the age of 50, and gender preference has been described.

Of all cancers involving the same class of blood cell (lymphoproliferative disorders), 22% of cases are follicular lymphomas.

In November 2013, ibrutinib was approved by the US FDA for treating MCL.

Other targeted agents include the proteasome inhibitor bortezomib, mTOR inhibitors such as temsirolimus, and the P110δ inhibitor GS-1101.

The germinal center subtype has the best prognosis,with 66.6% of treated patients surviving more than five years. The IPI score is used in prognosis in clinical practice. Lenalidomide has been recently shown to improve outcomes in the non-germinal center subtype. Ratios of immune effectors such as CD4 and CD8 to immune checkpoints such as PD-L1 and M2 macrophages are independent of and additive to the cell of origin and IPI in DLBCL, and are applicable to paraffin-embedded biopsy specimens. These findings might have potential implications for selection of patients for checkpoint blockade and/or lenalidomide within clinical trials.

For children with diffuse large B-cell lymphomas, most studies have found 5-year survival rates ranging from about 70% to more than 90%.

There is no consensus regarding the best treatment protocol. Several considerations should be taken into account including age, stage, and prognostic scores (see International Prognostic Index). Patients with advanced disease who are asymptomatic might benefit from a watch and wait approach, as early treatment does not provide survival benefit. When patients are symptomatic, specific treatment is required, which might include various combinations of alkylators, nucleoside analogues, anthracycline-containing chemotherapy regimens (e.g., CHOP), monoclonal antibodies (e.g. rituximab),

radioimmunotherapy, autologous (self) and allogeneic (donor) hematopoietic stem cell transplantation. Follicular lymphoma is regarded as incurable, unless the disease is localized, in which case it can be cured by local irradiation. Although allogeneic stem cell transplantation may be curative, the mortality from the procedure is too high to be a first line option.

In 2010 rituximab was approved by the European Commission for first-line maintenance treatment of follicular lymphoma. Pre-clinical evidence suggests that rituximab could be also used in combination with integrin inhibitors to overcome the resistance to rituximab mediated by stromal cells . However, follicular lymphoma which is CD20 negative will not benefit from Rituximab, which targets CD20.

Trial results released in June 2012 show that bendamustine, a drug first developed in East Germany in the 1960s, more than doubled disease progression-free survival when given along with rituximab. This combination therapy also left patients with fewer side effects than the older treatment (a combination of five drugs—rituximab, cyclophosphamide (Cytoxan), doxorubicin (Adriamycin), vincristine and prednisone, collectively called R-CHOP).

There are many recent and current clinical trials for follicular lymphoma. For example, personalised idiotype vaccines have shown promise, particularly as upfront therapy, but have still to prove their efficacy in randomized clinical trials.

The lymphoma is more common in the young and in males.

A 2008 study found an increased risk of ALCL of the breast in women with silicone breast implants (protheses), although the overall risk remained exceedingly low due to the rare occurrence of the tumor.

There is no known cause for any type of Marginal Zone non-Hodgkins lymphoma, but it occurs when the body produces large amounts of abnormal lymphocytes.

Factors that may increase an individuals chance of developing nodal MZL are being over the age of 60 and having been infected with hepatitis C virus. Factors that may increase an individuals chance of developing MALT lymphoma include being over the age of 50, having an autoimmune condition (rheumatoid arthritis, Hashimoto's thyroiditis), and long lasting chronic inflammation due to infection (H.pylori, Sjogren syndrome, chlamidia infection, Borrelia infection, Campylobacter jejuni infection). Factors that increase an individuals risk of developing splenic MZL include the hepatitis C virus, Epstein-Barr virus, malaria, Sjogren syndrome, and lupus.

In order to reduce the chances of developing MZL, an individual can decrease their exposure to the possible risk factors.

Breast implant-associated ALCL is a recently recognized lymphoma and definitive management and therapy is under evaluation. However, it appears that removal of the implant, and resection of the capsule around the implant as well as evaluation by medical and surgical oncologists are cornerstones. Still under evaluation is the extent of capsulectomy: partial versus complete capsulectomy; similarly it is not defined the significance of replacement of the implant in the affected breast, or the removal of contralateral implant. Similarly, the value of radiation therapy and chemotherapy are under evaluation.

Currently, there is a drug, LDK378, undergoing Phase III clinical trials at Vanderbilt University that targets ALK positive small cell lung cancer, and has showed clinical promise in its previous clinical trials. Because approximately 70% of ALCL neoplasms are also ALK positive, there is hope that similar highly selective and potent ALK inhibitors may be used in the future to treat ALK positive cases of ALCL.

Of all cancers involving the same class of blood cell, 2.3% of cases are Burkitt lymphoma. Epstein-Barr virus infection is strongly correlated with this cancer.

Of all cancers involving the same class of blood cell, 8% of cases are MALT lymphomas.

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.

Treatment is often dependent on if the lymphoma is causing issues in regards to the overall health of the individual. Since this a slow moving cancer, many patients start treatment when the symptoms appear. If the individual tests positive for hepatitis C, then anti-viral treatment is suggested since it will often get rid of the lymphoma as well. A splenectomy is generally taken as the initial form of treatment and used to confirm the diagnosis. Further treatment of this cancer is generally not needed until years later and may include chemotherapy, antibody therapy, and/or radiotherapy if the spleen was not initially removed.

This lymphoma is rare, comprising less than 5% of all cases, and is most common in young adults and adolescents. A distinct male gender preference has been described.

"MALT lymphoma" is exquisitely immunotherapy sensitive. Chemotherapy is reserved for those uncommon patients with disseminated disease at presentation or lack of response to local treatment. Rituximab, the anti-CD20 chimeric antibody, is a key component of therapy. Responses vary from 55% to 77% with monotherapy and 100% in combination with chemotherapy. Oral alkylating agents such as cyclophosphamide or chlorambucil have been administered for a median duration of 12 months with high rates of disease control (CR up to 75%) but appear not to be active in t(11;18) disease. The purine nucleoside analogs fludarabine and cladribine also demonstrate activity, the latter conferring a CR rate of 84% (100% in those with gastric primaries) in a small study. A pivotal study of rituximab plus chlorambucil compared with chlorambucil alone (IELSG-19 study, n = 227) demonstrated a significantly higher CR rate (78% vs. 65%; p = 0.017) and 5-year EFS (68% vs. 50%; p = 0.024) over chlorambucil alone. However, 5-year OS was not improved (88% in both arms). First-line treatment of choice is generally rituximab in combination with single alkylating agents or fludarabine, or a combination of all three drugs. The final results of this study, including the later addition of a rituximab-alone arm, are pending.

Two other genetic alterations are known:

- t(1;14)(p22;q32), which deregulates BCL10, at the locus 1p22.

- t(14;18)(q32;q21), which deregulates MALT1, at the locus 18q21.

These seem to turn on the same pathway as API2-MLT (i.e., that of NF-κB). They both act upon IGH, which is at the locus 14q32.

Under older classification systems, the following names were used:

Splenectomy can produce long-term remissions in patients whose spleens seem to be heavily involved, but its success rate is noticeably lower than cladribine or pentostatin. Splenectomies are also performed for patients whose persistently enlarged spleens cause significant discomfort or in patients whose persistently low platelet counts suggest Idiopathic thrombocytopenic purpura.

Bone marrow transplants are usually shunned in this highly treatable disease because of the inherent risks in the procedure. They may be considered for refractory cases in younger, otherwise healthy individuals. "Mini-transplants" are possible.

People with anemia or thrombocytopenia may also receive red blood cells and platelets through blood transfusions. Blood transfusions are always irradiated to remove white blood cells and thereby reduce the risk of graft-versus-host disease. Patients may also receive a hormone to stimulate production of red blood cells. These treatments may be medically necessary, but do not kill the hairy cells.

People with low neutrophil counts may be given filgrastim or a similar hormone to stimulate production of white blood cells. However, a 1999 study indicates that routine administration of this expensive injected drug has no practical value for HCL patients after cladribine administration. In this study, patients who received filgrastim were just as likely to experience a high fever and to be admitted to the hospital as those who did not, even though the drug artificially inflated their white blood cell counts. This study leaves open the possibility that filgrastim may still be appropriate for patients who have symptoms of infection, or at times other than shortly after cladribine treatment.

Although hairy cells are technically long-lived, instead of rapidly dividing, some late-stage patients are treated with broad-spectrum chemotherapy agents such as methotrexate that are effective at killing rapidly dividing cells. This is not typically attempted unless all other options have been exhausted and it is typically unsuccessful.

Patients with polymorphic variants (alleles) FCGR3A-48 and -158 were associated with improved categorical responses to rituximab-based treatments.