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According to the American Cancer Society, physicians will report close to 59,000 new cases of non-Hodgkin's lymphoma (NHL) during 2006. The society also predicts that about 19,000 of those new patients will die from the disease.

Certainly, the drug rituximab (Rituxan®), the first monoclonal antibody approved for cancer therapy by the FDA, has helped the medical profession make great strides in its fight against this disease. But what about patients who don't respond to chemotherapy and Rituxan?

Forrest General Hospital's (FGH) Cancer Center has recently introduced a unique treatment for non-Hodgkin's lumphoma — BEXXAR®.

"We're pleased to offer this kind of treatment at Forrest General," said Dr. William Woods, FGH radiation oncologist. "About one in three has a complete response to this treatment, meaning the cancer goes into remission."

Another radiation oncologist at FGH, Dr. Mike Cheng, laid out the basic patient criteria for the treatment. "First, the patient has to have failed to respond to all chemotherapy and Rituxan treatments," he said. "Then we have to determine that the patient's body will take up, will actually absorb, the antibody. To do this, we administer a small dose of the agent and observe how their body responds to it. Finally, the patient's bone marrow has to show no more than a 25 percent presence of cancer cells."

Assuming all these criteria are met, how does the treatment work?

To begin with, BEXXAR (the trade name for tositumomab) is used to treat a very specific type of NHL, specifically CD20 positive, follicular NHL that has recurred after previous treatment. It is the presence of the CD20 protein on the surface of these cancerous B cells that helps make the treatment so precise.

Basically, BEXXAR is a monoclonal antibody that has been combined with radioactive iodine. Because the antibody attaches to the CD20 site on the cancerous cells, BEXXAR allows the radiation to target these cells and to destroy them.

"The iodine gives off two kinds of radiation," said Cheng. "Beta radiation is a lower level radiation, which kills off the targeted lymphocytes. It also gives off gamma radiation, which is a stronger form of radiation. The gamma rays are especially helpful because they help us measure the progress of the treatment."

One of the best features of this treatment is that the dosage is quite patient-specific, based on measuring how the patient's body absorbs the antibody and their tolerance for the radioactive iodine.

"The body scan is important because some patients just don't take the antibody," said Cheng. "Also, the bottom line is that people respond very differently to radiation."

Cheng is pleased with the results he has seen thus far with BEXXAR, and he notes that it is the only option for many patients. "For some non-Hodgkin's patients, there is no other treatment modality that works," he observed. "In cases like that, it is important that we can offer a treatment like BEXXAR."

Combining biological and radiation therapies, BEXXAR is a form of radioimmunotherapy. Specifically, it is known as intensity-modulated radiation therapy, or IMRT. In IMRT, the treatment delivers a precise dose of radiation to a cancerous tumor while limiting the amount of radiation to which noncancerous tissues are exposed.

Cheng said, "I think radioimmunotherapy is the way of the future in cancer treatment. If we have a specific antibody that can target a particular kind of cell, that is better than what we have now, which is a kind of a shotgun approach by comparison. Really, the basic idea of using radiation as a treatment has been around for over 20 years, but now we have a much more sophisticated approach in how we can apply it."

Cheng is also pleased that FGH is able to offer such state-of-the-art treatment. "Cancer treatment should be given at home," he said. "It's so much better to be treated in your own community, close to family and friends, instead of having to travel far away and stay in a hotel room surrounded by strangers. This is why I am glad that we can offer the latest technology in a community hospital setting. It is a smaller setting, closer to home, but we have the same treatments available as the larger centers that are far away."

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