Credit: Rhoda Baer
SAN FRANCISCO—Results of a large study suggest that consolidation radiation therapy (RT) can improve survival in patients with stage I and II Hodgkin lymphoma (HL), but the use of RT in these patients may be on the decline.
In this study of more than 40,000 patients, the 10-year survival rate was 84% among those who received RT and 76% among those who did not.
Despite this benefit, the use of RT declined during the period studied, from 56% in 1998 to 41% in 2011.
These data were presented at the American Society for Radiation Oncology’s 56th Annual Meeting (abstract 1042).
“Multiple prospective, randomized trials have shown a significant improvement in disease control with the addition of RT,” said lead study author Rahul R. Parikh, MD, of the Mount Sinai Health System in New York.
“However, previous trials were limited by low patient numbers and limited follow-up and, thus, were unable to demonstrate an overall survival benefit. This is the largest dataset in this patient population to demonstrate a survival benefit with the addition of RT.”
Dr Parikh and his colleagues studied 41,502 patients who were diagnosed with stage I and II HL from 1998 to 2011. They were included in the National Cancer Data Base, which consists of cases from 1500 sites and represents more than 75% of all cancers diagnosed in the US.
The average patient age was 37 years (range, 18 to 90). The median follow-up was 7.5 years. Ninety-six percent of patients (n=39,842) received multi-agent chemotherapy, and 49% (n=20,441) received a median RT dose of 30.6 Gy.
The 10-year overall survival of the entire group was 80.8%. Patients receiving RT had significantly better overall survival than those who did not (84.4% vs 76.4%; P<0.00001).
When adjusting for age, stage, comorbidity, transplant, chemotherapy use, and socioeconomic status, RT use was still associated with significantly improved overall survival (hazard ratio=0.51; P<0.00001).
The study also showed that omitting RT was related to higher rates of salvage transplant procedures, a surrogate for persistent/relapsed disease (P=0.04).
Nevertheless, RT use decreased at the study sites from 56% to 41% between 1998 and 2011.
In 88.4% of patients who did not receive RT, the physician-reported reason was that RT was not part of the planned initial treatment strategy.
The research also indicated that RT use was more likely among younger patients (40 years or younger), those in a higher socioeconomic status, those who had access to health insurance, and those who received treatment at comprehensive cancer centers (all P<0.0001).
“[W]e have highlighted ongoing disparities in Hodgkin’s disease treatment, and it is important that we recognize these findings as potential barriers to care,” Dr Parikh said.
“Given the survival benefit demonstrated in this study, radiotherapy should be included in the combined modality approach of multi-agent chemotherapy followed by consolidation RT in order to maintain high overall survival rates for this curable disease.”
