Lymphoma is a general term for cancers that develop in the lymphatic system.
Lymphomas account for 3 percent of all cases of cancer in this country.
The most common type of lymphoma is called Hodgkin’s disease. All other lymphomas are grouped together and are called non-Hodgkin’s lymphomas.
The lymphatic system is part of the body’s immune defense system. Its job is to help fight diseases and infection.
The lymphatic system includes a network of thin tubes that branch, like blood vessels, into tissues throughout the body. Lymphatic vessels carry lymph, a colorless watery fluid that contains infection-fighting cells called lymphocytes. Along this network of vessels are groups of small, bean-shaped organs called lymph nodes. Clusters of lymph nodes are found in the underarms, groin, neck, chest, and abdomen.
Other parts of the lymphatic system are the spleen, thymus, tonsils, and bone marrow. Lymphatic tissue also is found in other parts of the body, including the stomach, intestines, and skin.
Like all types of cancer, lymphomas are diseases of the body’s cells. Healthy cells grow, divide, and replace themselves in an orderly manner. This process keeps the body in good repair. In the non-Hodgkin’s lymphomas, cells in the lymphatic system grow abnormally. They divide too rapidly and grow without any order. Too much tissue is formed, and tumors begin to grow. The cancer cells also can spread to other organs.
Malignant lymphocytes may be small and round or cleaved. Others may be large. Combinations of small and large cells may also be seen. Intermediate-sized lymphocytes with rapidly dividing cells are characteristic of aggressive (high-grade) lymphomas.
Within normal lymph nodes there are microscopic clusters (follicles) of specialized lymphocytes. In some malignant lymphomas, the lymphocytes arrange themselves in a similar pattern that is called follicular or nodular. Small cell and follicular lymphomas typically have a chronic course with an average survival of 6 to 12 years. In the more aggressive lymphomas, the normal appearance of the lymph node is lost by diffuse involvement of tumor cells, which are usually moderate-sized or large.
Hodgkin’s disease, the most common lymphoma, has special characteristics that distinguish it from the others. Often it is identified by the presence of a unique cell, called the Reed-Sternberg cell, in lymphatic tissue that has been surgically removed for biopsy.
Hodgkin’s disease tends to follow a more predictable pattern of spread, and its spread is generally more limited than that of the non-Hodgkin’s lymphomas. By contrast, the non-Hodgkin’s lymphomas are more likely to begin in extranodal sites (organs other than the lymph nodes, like the liver and bones).
There are about ten different types of Non-Hodgkin’s lymphoma. Some types spread more quickly than others. The type is determined by how the cells look under a microscope (histology). The histologies are grouped together, based on how quickly they spread, into low-grade, intermediate-grade, or high-grade lymphomas.
The cause of most lymphoma is unknown. Some occur in individuals taking drugs to suppress their immune system (i.e., post-transplant).
The most common symptom of non-Hodgkin’s lymphomas is a painless swelling in the lymph nodes of the neck, underarm, or groin. Other symptoms may include fevers, night sweats, tiredness, weight loss, itching, and reddened patches on the skin. Sometimes there is nausea, vomiting, or abdominal pain.
As lymphomas progress, the body is less able to fight infection. These symptoms are not sure signs of cancer, however. They also may be caused by many common illnesses, such as the flu or other infections. But it is important to see a doctor if any of these symptoms lasts longer than 2 weeks.
Treatment planning takes into account the type of lymphoma, the stage of disease, whether it is likely to grow slowly or rapidly, and the general health and age of the patient. Common treatment options for several types are as follows:
Low-grade lymphomas include small lymphocytic, follicular small cleaved, and follicular mixed cell. For low-grade lymphomas, which usually grow very slowly and cause few symptoms, the doctor may wait until the disease shows signs of spreading before starting treatment.
Although low-grade lymphomas grow slowly and respond readily to chemotherapy, they almost invariably return and are generally regarded as incurable. The long-term outcome has not been favorably affected by the use of intermediate chemotherapy. Single agent or combination chemotherapy or radiation therapy may be required when the disease progresses or begins to cause symptoms.
Intermediate and High Grades
Intermediate grade includes follicular large cell, diffuse small cleaved, diffuse mixed cell, and diffuse large cell. The chance of recovery and choice of treatment depend on the stage of the cancer, age, and overall condition. Whatever the origin, the features that best predict the prognosis and guide decisions about therapy are the size, shape and pattern of the lymphocytes as seen microscopically.
Intermediate- and high-grade lymphomas are curable. Treatment for intermediate- or high-grade lymphomas usually involves chemotherapy, with or without radiation therapy. In addition, surgery may be needed to remove a large tumor.
Combination chemotherapy is almost always necessary for successful treatment. Chemotherapy alone, or abbreviated chemotherapy and radiation, cure 70 to 80 percent of patients with limited (Stages I and II) intermediate-grade lymphoma. Advanced (Stages III and IV) disease can be eradicated in about 50 percent of patients.
The usual treatment for most patients with early stage Hodgkin’s disease is high-energy radiation of the lymph nodes. Research has shown that radiation therapy to large areas at high doses (3,500 to 4,500 rads) is more effective in preventing relapse than radiation of the diseased nodes alone.
Combination chemotherapy also is effective in the treatment of early stage Hodgkin’s disease. In addition, chemotherapy is the treatment of choice for advanced (stages III and IV) Hodgkin’s disease and for patients who have relapsed after radiotherapy. Drugs and radiation are sometimes given together, mainly in treating patients with tumors in the chest or abdomen.
What type of lymphoma is it?
How far has the disease spread? Is the disease in early or late stage?
How serious is the condition?
What treatment will you be recommending?
What can be expected from the treatment? Are there any complications to the treatments?
Will surgery be required now or possibly in the future? What is the procedure? What can be expected after the surgery?
What is the prognosis?
If nothing is done about this disease, what will happen?