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Glossary of Terms

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Performance status

A term used to describe a person’s ability to perform their activities of daily living.

Peripheral neuropathy

Damage to the nerves. This condition can be caused by some drugs and is usually characterized by tingling and weakness or numbness in the extremities.

Peripheral T-cell lymphoma (PTCL)

PTCL is a group of lymphomas defined by the types of mature-stage white blood cells (T-cells or natural killer (NK) cells) within the lymphatic system from which they arise.  The term “peripheral” refers to the fact that PTCL arises in the lymphoid tissues outside of the bone marrow such as lymph nodes, spleen, gastrointestinal tract and skin. When skin is involved, PTCL can share many features of cutaneous T-cell lymphoma (CTCL).

PET (positron emission tomography) scan

A type of test that may be used instead of gallium scans to identify areas in the body that are affected by lymphoma. This test evaluates metabolic activity in different parts of the body using a radioisotope.


An immunotherapy. It is a three to five hour procedure in which a portion of a patient's blood is taken out through the vein and the white blood cells are treated with PUVA phototherapy, after which they are then re-infused into the vein.


A form of skin-directed therapy that uses various forms of ultraviolet light and is often effective in clearing CTCL in its earliest stages, when the disease is confined to the skin (Stage I-A, I-B, II-A, II-B). Forms of phototherapy include PUVA, broadband UVB, and narrowband UVB.

Plasma cell

A mature B-cell that makes antibodies – these antibodies help the body destroy or remove toxins, bacteria and some cancer cells.

Primary cutaneous B-Cell lymphoma

Lymphomas that grow outside the nodal system, also called extranodal lymphomas, which are tumors that occur in organs or tissues outside the lymphatic system. When extranodal lymphomas originate in the skin and there is no evidence of systemic or extracutaneous disease, they are called primary cutaneous lymphomas and primary cutaneous B-cell lymphomas (CBCLs) when B-cells are involved.

Primary therapy

The first therapy given after a diagnosis of cancer.


The likely outcome of a disease, including the chance of recovery and survival.


A phototherapy treatment that uses Psoralens (P) in combination with ultraviolet light (UVA). Psoralens make the skin sensitive to the UVA. It is used to treat various skin disorders.

Radiation field

The part of the body that receives radiation therapy.

Radiation oncologist

A physician who specializes in treating cancer with radiation.

Radiation therapy

The use of radiation beams (X-rays) to treat a cancer.  High doses of high-energy radiation beams carefully focused on a tumor will kill cancer cells.  Radiation therapy (with or without chemotherapy) is sometimes used to treat CTCLs.


A therapy that is prepared by attaching a radioactive isotope to a monoclonal antibody.

Refractory disease

A cancer that is resistant to treatment.


A specific combination of drugs (chemotherapy), their doses and their schedules of administration.  A regimen may also include radiotherapy.


The return of cancer after treatment. Lymphoma may recur in the area where it first started or it may relapse in another area of the skin.


The absence of disease.  A patient is considered in remission when their lymphoma has been treated and tumors have diminished by at least 50 percent (partial) or have totally disappeared (complete).

Risk factors

Factors that may increase the chance that a person will develop a certain kind of disease.


A systemic therapy that has been shown to be very effective in treating CTCL. (Roferon is a name brand of interferon.)

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