Peripheral T cell lymphoma

• What is Peripheral T cell lymphoma
• Statistics on Peripheral T cell lymphoma
• Risk Factors for Peripheral T cell lymphoma
• Progression of Peripheral T cell lymphoma
• Symptoms of Peripheral T cell lymphoma
• Clinical Examination of Peripheral T cell lymphoma
• How is Peripheral T cell lymphoma Diagnosed?
• Prognosis of Peripheral T cell lymphoma
• How is Peripheral T cell lymphoma Treated?
• Peripheral T cell lymphoma References

What is Peripheral T cell lymphoma

Peripheral T cell lymphoma means cancer of the lymphatic system. The lymphatic system is important to our immune system where it helps to combat infection. The lymphatic system consists of several organs, e.g. lymph nodes, spleen, thymus and bone marrow, where all these are connected by tiny vessels. Lymphatic fluid is the medium that circulates in these tiny vessels. Like blood, it has cells in them. These cells can be divided into 2 types: T cells and B cells.
Lymphoma is divided into 2 broad groups: Hodgkin’s lymphoma and non-Hodgkin’s lymphoma. Peripheral T cell lymphoma is a non-Hodgkin’s lymphoma. As the name suggests, it primary affects the T cells. Peripheral T cell lymphoma has many subtypes as well, just to confuse the matter.

Statistics on Peripheral T cell lymphoma

Lymphoma is on the increase in the world over the years. The following figures is according to the Australian statistics:
 

• The incidence of non-Hodgkin’s lymphoma is increasing over the years.
• In 2001, there were 3499 cases of non-Hodgkin’s lymphoma.
• For non-Hodgkin’s lymphoma, the male:female ratio is 1.22:1.
• In 2000, there were 519 cases of T cell lymphoma (i.e. a subgroup of non-Hodgkin’s lymphoma) in Australia.Peripheral T cell lymphoma constitutes 15% of all non-Hodgkin lymphoma.
  

  Risk Factors for Peripheral T cell lymphoma

  Age: More common in adults than children
  Gender: Men are affected more than women but only slightly
  

  Progression of Peripheral T cell lymphoma

  Clinically and historically, non-Hodgkin’s lymphoma can be subdivided into 2 groups: indolent (low grade) and aggressive (high grade) lymphomas. Peripheral T cell lymphoma is under the aggressive group – which means it has worse prognosis but may respond to treatment modalities better than indolent group of lymphomas.
  The course of the disease is dependent on the clinical stage when the disease is diagnosed. The later the stage, the more advanced the disease is, hence worse outcome with the disease.
  The staging for non-Hodgkin lymphoma (which is applicable for peripheral T cell lymphoma) can be summarised as below:
  Stage I – involvement of a single lymph node region or organ or site other than lymph nodes
  Stage II – 2 or more lymph node regions involved on the same side of diaphragm
  Stage III – 2 or more lymph node regions involved on both sides of diaphragm
  Stage IV – one or more organs (eg bone marrow) involved
  Each stage is subclassified into A and B (eg IIA), where B means presence of B symptoms (see below) while A means abscence of the following symptoms:
   

• Unexplained fever > 38 Centigrade
• Unexplained weight loss (defined as >10% of body weight in 6 months)
• Night sweats
  

  How is Peripheral T cell lymphoma Diagnosed?

  The usual basic tests will be done, including those to look at the blood and other blood components. Other general tests will determine the function of the liver.
  

  Prognosis of Peripheral T cell lymphoma

  Generally the prognosis is worse than of B-cell lymphomas. Peripheral T-cell lymphoma is considered an aggressive non-Hodgkin’s lymphoma.
  The prognosis is dependent on the clinical stage when the disease is diagnosed. The later the stage, the worse the prognosis.
  Some criteria are associated with worse prognosis:
   

• Age >60 years old
• Serum lactate dehydrogenase (a type of biochemical compound found in the blood) concentration greater than normal
• Patient is having symptoms and in bed <50% of the day or worse than this
• More than 1 involved site other than lymph nodes (for example the bone marrow)The more these criteria are met, the worse the prognosis.
  

  How is Peripheral T cell lymphoma Treated?

  Peripheral T cell lymphoma is an aggressive lymphoma – it usually requires treatment options. The following treatment methodscan either be used alone or in combination depending on the state of the disease.
  The following treatment methods are typically used:
   

• Chemotherapy: this is using chemical (drugs) to kill the cancer cells.
• Radiotherapy: this is using radiation to kill the cancerous cells. This is used when there is one or more lymph node regions affected in the same part of the body.
• Steroids: these are the drugs often used with chemotherapy in order to reduce its side effects, for example, nausea and vomiting, etc.
• Bone marrow transplantation or Stem cell transplantation: this is first killing the cancer and normal lymphatic cells with chemotherapy and radiation, then infusing the body with non-cancerous new stem cells (cells that are precursor to the lymphatic system cells). However, this is limited to selected patients only due to the side effect profile of such treatment.
  

  Peripheral T cell lymphoma References

  [1] Cancer in Australia 2001 [online]. 2004 [Cited 2005 September 10th]. Available from: URL: http://www.aihw.gov.au/publications/can/ca01/ca01-c03.pdf
  [2] Clinical and pathologic features of mature peripheral T and NK cell lymphomas. 2005 [Cited 2005 September 10th]. Available from: URL: http://uptodateonline.com/application/topic.asp?file=lymphoma/12843
  [3] Lymphoma – An Overview [online]. 2004 [Cited 2005 September 10th]. Available from: URL: http://www.nccs.com.sg/epub/CU/vol2_04/lymphoma.htm