Chemotherapy
Chemotherapy involves the use of anti-cancer drugs, taken orally or intravenously. These drugs destroy cancer cells by interfering with their growth or by preventing them from reproducing.

Chemotherapy is the main treatment strategy for non-Hodgkin's lymphoma, except for people with low-grade Stage I or II disease. These patients receive radiation therapy alone, except for those with Stage II disease and other unfavorable prognostic factors such as poor health and old age.

There are several drug regimens for treating non-Hodgkin's lymphoma. These are broken down into four categories: single-drug treatments, including chlorambucil and cyclophosphamide; first-generation combinations not including the drug adriamycin; adriamycin-containing, or second-generation, combinations; intensive "third-generation" combinations (ProMACE-CytaBOM, MACOP-B, COP-BLAM); and special combinations for high-grade lymphomas. The third-generation combinations are highly effective, but also extremely toxic. CHOP remains the standard treatment for advanced intermediate non-Hodgkin's lymphoma.

Following are six drug combinations commonly used:

CVP: Cyclophosphamide, vincristine, prednisone. C-MOPP: Cyclophosphamide, oncovin, prednisone, procarbazine.
CHOP: Cyclophosphamide, vincristine, adriamycin, prednisone.
m-BACOD: Cyclophosphamide, vincristine, adriamycin, bleomycin, methotrexate, leucovorin, dexamethasone.
Pro-MACE CytaBOM: Cyclophosphamide, adriamycin, etoposide, prednisone, vincristine, cytosine arabinoside, bleomycin, methotrexate, leucovorin.
MACOP-B: Cyclophosphamide, adriamycin, vincristine, prednisone, bleomycin, methotrexate, leukovorin.

Monoclonal Antibodies
Antibodies are proteins produced by the immune system in tiny amounts to fight infection. Scientists are now able to make large amounts of a single antibody, which are known as monoclonal antibodies. Scientists have been working since the early 1980s to use monoclonal antibodies in cancer treatment, either with these proteins alone or by using them to deliver a radioactive or toxic "payload" directly to the tumor.

The Food and Drug Administration approved the monoclonal antibody rituximab in 1997 for treating relapsed or refractory (not responding to treatment) low-grade and follicular B-cell non-Hodgkin's lymphoma. Rituximab works by targeting a cell-surface molecule called CD20. When the antibody attaches to this antigen, scientists believe, some lymphoma cells die and others appear to become more susceptible to chemotherapy. The drug can be given on an outpatient basis, once a week for four consecutive weeks.

Other monoclonal antibodies are currently undergoing clinical trials for use in lymphoma, including antibodies to CD20 with radioactive particles attached.

Interferons
Interferons are proteins produced by the body in response to infection. They are also made artificially in laboratories. Given alone or together with chemotherapy, they have been helpful in treating some types of low-grade lymphoma.

A major drawback of interferon is the flu-like side effects it produces. A new form of the drug, which will be less toxic, is expected to become available in late 1999.