The Journal of Clinical Oncology has recently published a study reporting that there is no survival benefit among patients treated with chemotherapy and radiation when compared to patients treated with chemotherapy alone.
Lymphomas are a malignancy in which cancerous cells arise from the cells of the lymphatic system. The lymphatic system is a drainage system within the body, whose two primary functions are to maintain fluid balance and produce cells called lymphocytes, which fight infection. Lymphomas are divided into two types: non-Hodgkin’s lymphoma and Hodgkin’s lymphoma. Hodgkin’s lymphoma is characterized by the presence of Reed-Sternberg cells. There are five different types of Hodgkin’s lymphomas, each of which are characterized by the cell’s appearance under a microscope. Current treatment options for Hodgkin’s lymphoma include surgery, chemotherapy, and radiation. Other treatments, such as high dose chemotherapy and radiation with stem cell transplantation, are being studied in clinical trials.
In many cases, treatment of limited-stage Hodgkin’s lymphoma may include a combination of chemotherapy and possibly radiation. Patients frequently are treated with a regimen known as “ABVD” chemotherapy, which includes a combination of the drugs doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). In this recent study, patients with stage IA or IIA Hodgkin’s lymphoma were categorized according to their risk factors into favorable or unfavorable risk groups. Each patient was then randomized to receive either ABVD chemotherapy alone for 4 to 6 cycles (180 patients) or a treatment regimen containing radiation. Of the patients who were randomized to receive a radiation treatment regimen, further consideration was given for their risk status. Those patients who were considered to be among the unfavorable risk group (139 patients) were treated with two cycles of chemotherapy followed by radiation. Patients in the favorable risk group (53 patients) received radiation alone. A total of 399 patients were included in the study, and the average follow up was 4.2 years.
For patients with favorable features, there were no differences in outcomes between those receiving radiation therapy alone or chemotherapy; Event-free survivals were 88% and 87%, respectively. For the majority of patients with unfavorable features, the relapse rate was 5% in the combined radiation and chemotherapy group and 12% in the chemotherapy alone group. However, overall survival was 92% in the combined radiation and chemotherapy group and 95% in the chemotherapy alone group. The added anti-lymphoma effect of radiation therapy was offset by an increase in toxic deaths and secondary cancers. Researchers concluded that favorable patients could be treated with chemotherapy alone and that the addition of radiation therapy to chemotherapy in unfavorable patients did not improve survival. This study suggests that radiation therapy should be reserved for those patients with stage IA or IIA Hodgkin’s lymphoma who do not achieve a complete remission to chemotherapy alone.
Reference: Meyer R, Gospodarowicz M, Connors J. et al. Randomized Comparison of ABVD Chemotherapy With a Strategy That Includes Radiation Therapy in Patients With Limited Stage Hodgkin’s Lymphoma: National Cancer Institute of Canada Clinical Trials Group and the Eastern Cooperative Oncology Group. Journal of Clinical Oncology. 2005; 23; 4634-4642.