Radiation Therapy Improves Survival in Hodgkin's Lymphoma

Despite a recent decline in utilization, consolidated radiation therapy (RT) has been shown to improve 10-year survival rates for patients with stage I/II Hodgkin’s lymphoma following treatment with chemotherapy, according to data from a large analysis presented at the 2014 ASTRO Meeting. Abstract CT-08

The use of RT for patients with early-stage Hodgkin’s lymphoma has decreased from 56% to 41% between 1998 and 2011. In 88.4% of the patients, the physician-reported reason for not administering RT was that it was not part of the planned initial treatment strategy. Based on the results of the analysis, the authors of the study suggested that since combined modality therapy contributed significantly to the cure rate for patients with early stage Hodgkin’s lymphoma, RT should remain standard practice.

“Multiple prospective, randomized trials have shown a significant improvement in disease control with the addition of RT, however previous trials were limited by low patient numbers and limited follow-up and thus, were unable to demonstrate an overall survival benefit,” lead study author Rahul R. Parikh, MD, a radiation oncologist at Mount Sinai Beth Israel and an Assistant Professor of Radiation Oncology at Icahn School of Medicine at Mount Sinai, said in a statement. “This is the largest dataset in this patient population to demonstrate a survival benefit with the addition of RT.”

For the study, 41,502 patients with an average age of 37 who had been diagnosed with stage I and II Hodgkin’s lymphoma between 1998 and 2011 were selected from National Cancer Data Base. The median follow-up for patients in the database was 7.5 years. Of the patients selected, 96% (n= 39,842) had received multiagent chemotherapy and 49% (n = 20,441) had received RT at a median dose of 30.6 Gy.

The 10-year overall survival (OS) rate for the entire group of patients was 80.8%. After a median of 10 years, the OS rate for patients who received RT was 84.4% compared with 76.4% for those who did not (HR = 0.51; 95% CI, 0.46-0.56, P <.00001). The omission of RT was associated with higher rates of transplant procedures performed, a surrogate for persistent/relapsed disease (P =.04). Additionally, initiating chemotherapy within 30 days after diagnosis was associated with improved OS at 10 years (84.5% vs 78.3%, P <.00001), even when adjusting for all covariables (HR = 0.86; 95% CI 0.77-0.95, P = .005).

The research also indicated that RT use was associated with younger patients (≤40 years), who had a higher socioeconomic status, who had access to health insurance, and who received treatment at comprehensive cancer centers (P <.0001).

“Given that the utilization of RT was associated with younger age, insurance status, higher socioeconomic status, and treatment at comprehensive cancer centers, we have highlighted ongoing disparities in Hodgkin’s Disease treatment and it is important that we recognize these findings as potential barriers to care,” Parikh said.

“Given the survival benefit demon-strated in this study, radiotherapy should be included in the combined modality approach of multiagent chemotherapy followed by consolidation RT in order to maintain high overall survival rates for this curable disease.”

The adverse events associated with the addition of radiation therapy were not noted in the analysis. Short-term side effects of RT generally include skin reaction, fatigue, nausea, and diarrhea. In general, long-term adverse events represent a leading concern facing the administration of RT for patients with early-stage Hodgkin’s lymphoma. These side effects usually do not manifest for 10 to 20 years following treatment. While newer approaches for administering RT hope to ameliorate these concerns, further data are still required to analyze this risk.

Nurse Perspective

Phyllis McKiernan, MSN, APN, OCN

Blood and Marrow Transplant Program John Theurer Cancer Center Hackensack, NJ

Radiation therapy (RT) in combination with chemotherapy has been a common treatment for early stage Hodgkin’s lymphoma. Previous studies have shown using RT results in an improvement in controlling the disease; however, due to low enrollment and lack of long-term follow up, improved overall survival has not been clearly identified. This large analysis of more than 41,000 patients with Hodgkin’s lymphoma diagnosed and treated during a 13-year period, shows that patients who received multi-agent chemotherapy with consolidative radiotherapy have significantly improved survival over patients who did not receive radiation.

Physicians report a recent decline in the use of RT for early stage Hodgkin’s. Reasons for not including RT in the treatment plan include lack of data regarding long-term overall survival and side effects. Short-term side effects of radiation are generally well-tolerated and controlled with supportive care, such as antiemetics, antidiarrheals, and good skin care. However, the long-term effects can include secondary malignancies, and this could impact on treatment decisions, especially when long-term benefit versus risk has not been clear. Newer techniques for administering radiation that limit the field and exposure to uninvolved tissue may mitigate this risk, but more research and long-term follow-up is needed. This latest research, with demonstrated improvement in outcomes, supports the use of RT for this patient population and should be considered as part of the initial treatment plan.

The interesting finding that younger patients from a higher socioeconomic group with access to comprehensive cancer centers are more likely to receive RT highlights the disparity that exists in healthcare today. In a perfect world, all patients should have access to the same information and state-of-the art care, but in the real world, this remains a challenge. Patients across all socioeconomic groups need to be educated by healthcare professionals about the most current information pertaining to their disease with risks versus benefits and take part in the treatment planning process.