Combined modality therapy (CMT) — chemotherapy plus radiation therapy — was associated with improved survival in young Hodgkin lymphoma patients compared with chemotherapy alone, an observational study found.
At a median follow-up of 61.8 months, patients selected to receive CMT had a 5-year overall survival of 97.3% compared with 94.5% for those treated with chemotherapy alone, according to Rahul R. Parikh, MD, of Rutgers Cancer Institute of New Jersey, and colleagues.
And this remained significant on multivariable analysis that accounted for patients’ age, sex, race, health insurance type, tumor stage, presence of B symptoms, and transplant procedure (adjusted HR 0.57, 95% CI 0.42-0.78, P<0.001), as reported in JAMA Oncology.
“This study demonstrates improvement in survival benefit for pediatric Hodgkin lymphoma patients,” Parikh said in a press release. “With that, physicians should be encouraged to discuss combined modality therapy as one of the many treatment options with them at the time of diagnosis.”
The most benefit with CMT was seen in patients ages 15 years and older (adjusted HR 0.47, 95% CI 0.40-0.56, P<0.001).
The authors noted in the finding that patients ages 1 to 13 years derived the least additional benefit from adding RT is of particular interest, as these patients are the most “vulnerable” to late effects from radiation therapy.
“As multiple disparities to the use of combined modality therapy have been identified through this work, future studies should address improving access to care for all pediatric patients,” Parikh said.
CMT in early-stage pediatric Hodgkin lymphoma has demonstrated event-free and overall survival rates over 80% and 95%, respectively. But the use of radiation therapy has fallen off in recent years due to adverse effects seen in long-term follow-up — cardiac and lung toxicities, secondary malignancies, as well as infertility and endocrine abnormalities. In 2004, CMT was used in 59.7% of patients, but this dropped to 34.9% of patients in 2015.
“Nationwide, there has been a notable decrease in combined modality therapy, especially in clinical trials, many of which are designed to avoid this strategy,” explained Parikh. “The question then becomes, ‘does treatment benefit outweigh the risk of long-term side effects?'”
For the current study, the researchers used data on 5,657 patients (mean age 17.1) from the National Cancer Database who were diagnosed with stage I-II classic Hodgkin lymphoma from 2004 to 2015. Most of the patients were white (82.9%) and the majority were female (53%). Males were more likely to receive CMT than females (48.1% vs 43.6%).
In most cases where CMT was not used, it was due to the fact that it had not been part of the physician’s initial treatment strategy (90.9%), though in some cases patients refused (1.7%).
Limitations of the study included the fact that the data set lacked information on certain prognostic factors such as systemic symptoms of the lymphoma, number of nodal sites, and presence of bulky disease. The short follow-up also does not fully capture late effects associated with use of radiation therapy.
Parikh and colleagues reported no conflicts of interest.