NEJM: Chemo without rad therapy improves Hodgkins survival rate
The treatment of stage IA or IIA nonbulky Hodgkin’s lymphoma with chemotherapy alone is controversial given that strategies combining chemotherapy with radiation treatment have been shown to control the disease in up to 90 percent of patients, according to study authors Ralph M. Meyer, MD, of Queen’s University in Kingston, Ontario, Canada, and colleagues. Combination treatments, however, are associated with late treatment-related deaths, which the researchers hypothesized may mean chemotherapy treatments by themselves can improve overall survival.
To test the different treatment strategies, researchers randomly assigned 405 patients with untreated stage IA or IIA nonbulky Hodgkin’s lymphoma to treatment with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) alone or to treatments featuring subtotal nodal radiation therapy, with or without ABVD therapy.
Results at 12-year follow-up showed the overall survival rate among patients receiving ABVD alone was 94 percent compared with 87 percent among those receiving subtotal nodal radiation therapy. Radiation therapy resulted in higher rates of freedom from disease (92 percent compared with 87 percent for ABVD alone), however, the rate of event-free survival was 85 percent with ABVD alone and was reduced to 80 percent in patients receiving radiation therapy.
“As postulated by the study hypothesis, the advantage that is seen with chemotherapy alone is due to the fact that there are fewer deaths from causes other than progressive Hodgkin's lymphoma or acute treatment-related toxic effects,” wrote the authors.
The researchers reported that six patients randomly assigned to ABVD alone died from Hodgkin’s lymphoma or an early treatment complication and six died from another cause. Among patients receiving radiation therapy, four deaths were related to Hodgkin’s lymphoma or early toxic effect and 20 were related to other causes.
Meyer et al wrote that the results of their study have implications for future clinical trials of IA or IIA Hodgkin’s lymphoma treatment therapies.
“Our results show that improving long-term survival is less dependent than previously assumed on further reducing deaths due to progressive Hodgkin's lymphoma and instead emphasize a need for treatments that will not lead to deaths from late treatment effects,” wrote the authors. “Thus, trial end points should be redefined so that the importance of deaths from causes other than Hodgkin's lymphoma is captured.”