Combined data from five randomized clinical trials indicate that patients with early-stage Hodgkin's lymphoma should receive radiation therapy in addition to chemotherapy. The combination of the two therapies is currently the standard treatment for Hodgkin lymphoma.

However, some researchers have suggested that forgoing radiation therapy may not lower survival for patients with early-stage disease. Radiation therapy can cause late side effects in survivors, who tend to be young at the time of treatment. These side effects include second cancers, most commonly breast cancer in young women who receive radiation therapy to the chest.

Researchers from the Cochrane Collaboration performed a meta-analysis using data from 1,245 patients enrolled in the five trials. Each trial compared outcomes among patients treated with six cycles of chemotherapy alone with those among patients treated with six cycles of chemotherapy plus radiation therapy. Patients had stage I or stage II disease and either a favorable or unfavorable prognosis. Median follow-up for the trials ranged between 2 and 11.4 years.

Patients who received the combination of radiation therapy and chemotherapy lived longer than patients who received chemotherapy alone. The authors estimated that one life would be saved for every 11 to 55 patients treated with combination therapy instead of chemotherapy alone. Patients who received combination therapy also had a lower risk of relapse. For every six patients treated with combination therapy instead of chemotherapy alone, the authors estimated, one relapse would be prevented.

Patients receiving either treatment experienced similar side effects during the trials. However, "long-term adverse effects such as secondary malignancies...can occur later than the reported observation times of the discussed trials," explained the authors. This long lag time makes it impossible to determine from the available data if deaths due to late side effects differ between the two groups.

Two ongoing clinical trials are testing whether positron emission tomography (PET) scans can be used to determine if some patients with early-stage Hodgkin lymphoma can safely skip radiation therapy.

Source: NCI