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Subtypes of non-Hodgkin lymphoma
There are many different types of non-Hodgkin lymphoma. The types are generally described
by how quickly the cancer is growing: low grade (indolent), and high-grade (aggressive)
forms. NHL is more common in adults, in whom the low grade and aggressive NHLs are about
equally common. High-grade non-Hodgkin lymphomas are most common in children.
Low grade lymphomas are slow-growing (indolent). These types of lymphoma
grow very slowly and tend to be advanced by the time they cause symptoms. Around 85% to
90% of patients with these conditions have advanced (stage IV, see below) disease when
they first visit an oncologist. They grow slowly, and usually respond well to several
different types of treatment. They are usually not curable.
High grade lymphomas are rapidly growing (aggressive). These types of
lymphoma grow rapidly, sometimes very rapidly. These conditions usually require
chemotherapy that is sometimes very intensive. These conditions are often curable.
Some lymphomas cannot be easily classified as low grade or high grade. For example, mantle
cell lymphoma has features of both high grade and low grade lymphoma.
There are 35 recognized subtypes of non-Hodgkin lymphoma.
Doctors use symptoms, blood tests and genetic analyses to determine the subtype. It is
very important to identify each person's subtype because they can behave very differently,
and require different treatments. They are classified using the World Health Organization
Classification.
Subtypes describe the form of the cancer cells and the structure of the cancerous
lymphatic tissue when viewed under the microscope. Follicular lymphoma cells form
clusters, also known as follicles, while diffuse cells are evenly distributed through
lymphatic tissue. Non-Hodgkin lymphomas also are classified by whether they affect the B
or T cells of the immune system. Some subtypes are described by the parts of the body
involved: the lymph nodes (nodal), spleen (splenic), chest area (mediastinal) or other
organs (extranodal).
B-cell lymphomas make up about 90% of all cases of lymphoma.
The most common subtypes of B-cell lymphoma:
Diffuse large B-cell lymphoma: The most common form of lymphoma (about
30% of all cases of NHL). Occurs outside the lymph nodes in about 40% of cases, and is
considered an aggressive form of NHL. People with diffuse large cell lymphomas most often
have large masses, weight loss, night sweats, and fever. This type of lymphoma is very
often curable with a combination of radiation therapy and doxorubicin-based chemotherapy.
Some people may also receive chemotherapy to the central nervous system to prevent the
lymphoma from spreading (called CNS prophylaxis).
Follicular lymphoma: The second most common form of lymphoma in the
United States and Europe, about 20% of all cases of NHL. It usually begins in the lymph
nodes, is most often low grade, and moves very slowly. There is no known cure, and most
people survive 8 to 10 years after diagnosis. People with follicular lymphomas may be
treated with combination chemotherapy, or may be followed closely with watchful waiting.
Stem cell transplants, tumor vaccines, interferon, and monoclonal antibody treatments may
also be available in clinical trials.
Splenic marginal zone B-cell lymphoma (with or without villous
lymphocytes): a form of lymphoma that begins in the spleen. It is an uncommon form of
B-cell chronic lymphocytic lymphoma (CLL). It is usually slow-acting and often requires no
treatment. Sometimes, surgical removal of the spleen is recommended.
Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue
(MALT) type: most commonly occurs in the stomach; also in the lung, thyroid,
salivary gland, or eye. People with this form of lymphoma often have a history of
autoimmune disease. When MALT occurs in the stomach, it is often treated successfully with
antibiotics. In other cases, radiation, surgery, chemotherapy, or a combination of these
is the most common treatment. In general, these lymphomas are treated similarly to diffuse
large cell lymphoma.
Nodal marginal zone B-cell lymphoma (with or without monocytoid B cells).
Involves the lymph nodes. Rare, about 1% of all lymphomas. In general, these lymphomas are
treated similarly to diffuse large cell lymphoma.
Lymphoplasmacytic lymphoma: Rare (1% of all NHL), indolent (low grade)
form of lymphoma. This form of lymphoma most often involves the bone marrow, lymph nodes,
and spleen. People with lymphoplasmacytic lymphoma often experience hyperviscosity
(thickened blood) that may cause them to feel chills. Treatments are similar to chronic
lymphocytic lymphoma/leukemia, and may include combination chemotherapy, watchful waiting,
interferon, or monoclonal antibodies. Chemotherapy followed by stem cell transplant is
being explored in clinical trials.
Mantle cell lymphoma: An aggressive form of NHL that makes up 7% of all
NHL. It most often appears with no symptoms in people over age 60. It most often involves
the bone marrow, lymph nodes, spleen, and gastrointestinal system, and is identified by
its expression of a protein called the cyclin D1 protein. People with mantle cell lymphoma
also exhibit a translocation of two chromosomes (11 and 14), which means that parts of
these two chromosomes have traded places. Mantle cell lymphoma is considered an aggressive
type of lymphoma, and often does not respond or stops responding to chemotherapy. Clinical
trials of mantle cell lymphoma using high dose chemotherapy followed by stem cell
transplant, interferon, or monoclonal antibodies after CHOP chemotherapy are in progress.
Mediastinal large B-cell lymphoma: An aggressive form of diffuse large
B-cell lymphoma that appears as a large mass in the chest area that may cause respiratory
symptoms or superior vena cava (SVC) syndrome. It is most common in women between the ages
of 30 and 40, and represents about 2.5% of all NHL cases. It is treated with high doses of
chemotherapy, and may also respond to stem cell transplant.
Primary effusion lymphoma: This very aggressive form of lymphoma most
often occurs in people who are HIV-positive. It appears in the lung, heart, or abdominal
cavities, and often there is not one identifiable tumor mass. It is treated as other
diffuse large cell lymphomas.
Burkitt's lymphoma/Burkitt's cell leukemia: A very rare and aggressive
form of lymphoma. There are three forms of Burkitt's lymphoma: endemic, sporadic, and
immunodeficiency-related. It occurs most commonly in Africa, in the jawbones of children,
and is associated with the Epstein-Barr virus. Burkitt's lymphoma is identified by a
specific translocation and inactivity of the c-myc gene on chromosomes. It is an
aggressive type of lymphoma, and is often curable with doxorubicin-based chemotherapy.
Bone marrow transplants for Burkitt's lymphoma are underway.
T-cell lymphomas make up about 10% of all lymphoma cases.
The most common subtypes of T- and natural killer (NK-) cell lymphomas:
Precursor T-lymphoblastic lymphoma/leukemia (precursor T-cell acute
lymphoblastic leukemia): Makes up about 15% of all childhood and about 25% of all adult
ALL (acute lymphocytic lymphoma)[link]. It is most common in late childhood, adolescence,
and early adulthood, and is more common in men. It is called leukemia if there are more
than 25% bone marrow blasts (early white blood cells); and lymphoma is there are fewer
than 25% bone marrow blasts and a mass forming in the chest area (mediastinal mass).
Lymphoblastic lymphoma most often begins as a large mass in the chest area that moves
quickly to the bone marrow. This is considered a very aggressive form of lymphoma. It is
treated with intensive chemotherapy with bone marrow transplant, and may include radiation
therapy.
Adult T-cell lymphoma/leukemia (human T-cell lymphotropic virus type I
positive): This type of lymphoma is caused by a virus called the human T-cell lymphotropic
virus type I. It is an aggressive disease that most often involves the bone and skin;
often leukemia cells are found in the blood. This form of lymphoma usually has a poor
response to chemotherapy, though some successes have been seen with zidovudine and
interferon. About two thirds of patients experience remission.
Extranodal NK/T-cell lymphoma, nasal type: This is an aggressive type of
lymphoma, very rare in the United States and Europe but more common in Asian and Hispanic
communities. It can occur in children or adults, and most often involves the nasal area,
but can also involve the trachea, gastrointestinal tract, or skin. It often does not
respond well to standard chemotherapy, but may be treated with radiation therapy followed
by chemotherapy. Bone marrow or peripheral stem cell transplantation for this type of
lymphoma is being studied in clinical trials.
Enteropathy type T-cell lymphoma: Rare in the United States and Europe.
This is an aggressive form of T-cell lymphoma that involves the intestines of people who
have celiac disease (gluten intolerance). If left untreated, it can damage the intestines
severely. This type of lymphoma is preventable if people who know they have celiac disease
adopt a gluten-free diet. High dose chemotherapy may be used to treat enteropathy type
T-cell lymphoma.
Hepatosplenic T-cell lymphoma: This is an aggressive form of peripheral
T-cell lymphoma that involves the liver and spleen. It occurs most often in male
adolescents and young men. It is treated as a high-risk diffuse large cell lymphoma.
Subcutaneous panniculitis-like T-cell lymphoma: This is a form of
peripheral T-cell lymphoma that involves the tissues under the skin, and is often first
diagnosed as panniculitis (inflammation of fatty tissues). It is treated as a high-risk
diffuse large cell lymphoma.
Anaplastic large cell lymphoma, T/null-cell, primary cutaneous type: This
is an aggressive form of lymphoma that involves the skin only. It is often successfully
treated with doxorubicin-based chemotherapy.
Peripheral T-cell lymphoma: This is an aggressive form of lymphoma, most often discovered
at an advanced stage. It is most common people over age 60, and makes up about 6% of all
lymphomas in the United States and Europe. It involves either diffuse large or diffuse
mixed cells that express certain types of proteins (CD4 or CD8) on a blood test. It is
treated like diffuse large B-cell lymphoma, with doxorubicin-based chemotherapy. Stem cell
transplantation may be considered in some cases.
Angioimmunoblastic T-cell lymphoma: This is a moderately aggressive form
of lymphoma marked by the symptoms it produces: swollen lymph nodes, fever, weight loss,
skin rash, and high levels of antibodies called gamma globulin in the blood. Since people
with angioblastic lymphoma have depressed immune systems, infections are also common. This
type of lymphoma is identified by specific genetic alterations on the T-cell receptors. It
is managed like other diffuse large cell lymphomas.
Anaplastic large cell lymphoma, T/null cell, primary systemic type: This
form makes up about 2% of all lymphomas, and about 10% of all childhood lymphomas. It
occurs in both adults and children. It is an aggressive form of lymphoma but often
responds well to treatment. |
