Approach resulted in high remission rates without the risks tied to radiotherapy, researchers say
WEDNESDAY, April 10, 2013 (HealthDay News) -- A new treatment approach may mean that young people with a form of lymphoma can go without radiation therapy, sparing them side effects or raised cancer risks down the road.
In a trial conducted by the U.S. National Cancer Institute, nearly all patients with a form of cancer known as primary mediastinal B-cell lymphoma who received chemotherapy, but did not undergo chest radiation, achieved a full remission.
Standard treatment for this cancer typically includes radiation to the chest, the study authors pointed out, but this has been linked to significant harmful effects in the future, particularly for women.
"These results are exciting and demonstrate that, using this approach, almost all patients appear to be cured and very few patients require radiation," study co-author Dr. Kieron Dunleavy, of the U.S. National Cancer Institute, said in an agency news release.
One expert not connected to the study agreed.
"This study is a significant achievement in improving the care of a group of lymphoma patients that urgently need it: young patients with an aggressive and -- if left untreated -- rapidly lethal disease," said Dr. Joshua Brody, assistant professor of medicine at the Icahn School of Medicine at Mount Sinai in New York City.
The study "yielded very exciting success rates with almost all patients going into complete remission even without the use of radiation therapy, which is frequently used for this disease," Brody added. All of the patients in the study maintained remission "for a long time," he noted, and "most of the patients are certainly cured of their disease."
The study is published in the April 11 issue of the New England Journal of Medicine.
Primary mediastinal B-cell lymphoma usually affects people in their teens to early 30s. Although many people with the disease who are treated with both chemotherapy and radiation do achieve a cure, roughly 20 percent do not, according to an NCI news release.
The research team noted that radiation to the chest area could also boost a patient's risk for other types of cancer down the road, including breast cancer, as well as cause damage to the heart. Complicating matters, as young people age, their risk for heart disease and new forms of cancer also rises.
The NCI trial involved 51 patients with untreated primary mediastinal B-cell lymphoma who were followed over the course of 14 years. The largest tumor diameter of any patient in the study was 11 centimeters.
Each patient received a regimen of drugs known as dose-adjusted EPOCH-R. The regimen included the following drugs: etoposide, doxorubicin, cyclophosphamide, vincristine, prednisone and rituximab. The dosages of these drugs were adjusted to make them as effective as possible.
In the study, only two patients who received this dose-adjusted chemotherapy treatment did not go on to achieve complete remission. These two patients, the researchers noted, also received radiation and have not had their tumors come back.
Meanwhile, none of the patients who did achieve a complete remission experienced disease recurrence. The researchers added there were no signs of heart damage or other long-term negative health effects among the patients.
"The high success of this regimen in greatly reducing the need for radiation and improving the cure rate in this disease may relate to specialized dosing and continuous infusion delivery of the EPOCH-R agents," explained lead researcher Dr. Wyndham Wilson, head of the NCI's Lymphoma Therapeutics Section.
Wilson and his colleagues also collaborated with researchers at Stanford University who used the regimen to treat their own group of 16 slightly older patients with primary mediastinal B-cell lymphoma. The Stanford study found all 16 patients who received the dose-adjusted chemotherapy regimen achieved full remission and none of them required radiation.
Other experts were optimistic about the research.
"What is encouraging is the fact that so many patients did well without radiotherapy, which will reduce the risk these patients have of developing late complications, including secondary solid tumors, acute leukemia and cardiac disease," said Dr. Jonathan Kolitz, associate chief of hematological oncology at the North Shore-LIJ Cancer Institute in Lake Success, N.Y. He stressed, however, that more research needs to be done to confirm that the new approach "is truly superior to the more conventional administration" used today.
Dr. Alan Astrow is director of hematology/medical oncology at Maimonides Cancer Center in New York City. He called the findings "highly impressive results."
"It appears that radiation therapy is not required for patients with primary mediastinal B-cell lymphoma who achieve a complete response after treatment with the reported chemotherapy regimen," he said.
For his part, Brody said the new results are exactly what most physicians long to see.
"Oncologists go into this business to try to save lives but, truthfully, the opportunity to save the lives of young, healthy people, and give them back a whole lifetime of quality time . . . is particularly gratifying," Brody said.
The Leukemia & Lymphoma Society provides more information on lymphoma (http://www.lls.org/diseaseinformation/lymphoma/ ).
SOURCES: Alan B. Astrow, M.D., director, hematology/medical oncology, Maimonides Cancer Center, New York City; Joshua Brody, M.D., assistant professor, medicine, Icahn School of Medicine at Mount Sinai, New York City; Jonathan Kolitz, M.D., associate chief, hematological oncology, North Shore-LIJ Cancer Institute, Lake Success, N.Y.; U.S. National Cancer Institute, news release, April 10, 2013