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Non-Hodgkin lymphoma

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Peripheral T-cell lymphoma, unspecified

Peripheral T-cell lymphoma, unspecified (or not otherwise characterized) develops from mature T-cell lymphocytes. Peripheral T-cell lymphoma, unspecified (PTCLU or PTCLUS) is the most common type of T-cell non-Hodgkin lymphoma. PTCLU includes a mixed group of mature T-cell cancers that are less well defined than the other T-cell subtypes. They do not have consistent genetic or biological characteristics, so they don’t exactly fit into the other T-cell types of lymphomas.

PTCLU makes up about 6–7% of all lymphomas. It is more common in Japan and other Asian countries than it is in North America or European countries.

PTCLU typically occurs in adults, often in people in their 60s.

PTCLU mainly affects the lymph nodes. However, it can sometimes affect organs or tissues other than the lymph nodes (extranodal sites), such as the bone marrow, skin, liver, spleen, lung or gastrointestinal tract.

PTCLU tends to grow quickly and be widespread, so it is considered to be an aggressive lymphoma. Most people are diagnosed at an advanced stage (stage III or IV) and have unfavourable prognostic factors. Relapses are common and the prognosis is often not as good for PTCLU as for B-cell lymphomas.


PTCLU is usually treated the same way as diffuse large B-cell lymphoma (DLBCL). Treatment for PTCLU is usually a combination of chemotherapy drugs.


The most commonly used combination chemotherapy for treating PTCLU is CHOP:

  • cyclophosphamide (Cytoxan, Procytox)
  • doxorubicin (Adriamycin)
  • vincristine (Oncovin)
  • prednisone (Deltasone)

CHOP-like combinations of chemotherapy may also be used. Some single chemotherapy drugs that can be used include:

  • fludarabine (Fludara)
  • cladribine (2-CDA, Leustatin)
  • pentostatin (deoxycoformycin, Nipent)
  • gemcitabine (Gemzar)

Radiation therapy

Sometimes external beam radiation therapy may be used in combination with chemotherapy to treat lymph node areas in people with early stage PTCLU.

Biological therapy

Monoclonal antibodies are a type of biological therapy that is effective in treating certain types of NHL. Although rituximab (Rituxan) is commonly used to treat people with DLBCL, rituximab is not usually used to treat PTCLU. However, another biological therapy drug, alemtuzumab (Campath), may be offered to some people with PTCLU later in treatment, if other therapies are no longer working.

Stem cell transplant

A stem cell transplant (SCT) may be offered to some people with PTCLU who responded to chemotherapy, particularly when they relapse after treatment.

Targeted therapy

Romidepsin (Istodax) is a newer drug that may be used to treat peripheral T-cell lymphoma. It is a type of targeted therapy. Targeted therapy uses drugs to target specific molecules (such as proteins) on the surface of cancer cells. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells while limiting harm to normal cells.


Romidepsin is a histone deacetylase (HDAC) inhibitor. It lowers the activity of HDAC, which slows or stops the growth of cancer cells or causes them to die. It may help people who have had at least one chemotherapy regimen and relapse or no longer respond to treatment, but who can’t have a stem cell transplant.

For more detailed information on specific drugs, go to sources of drug information.


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