Combined modality therapy (CMT) can improve survival in young patients with early stage Hodgkin lymphoma (HL), according to research published in JAMA Oncology.
In a retrospective study, researchers compared chemotherapy followed by radiotherapy—CMT—to chemotherapy alone in more than 5,600 HL patients age 21 and younger.
There was a significant improvement in 5-year overall survival (OS) among patients who received CMT.
The treatment appeared particularly beneficial for adolescents and young adults as well as patients with low-risk disease.
However, the researchers observed a nearly 25% decrease in the use of CMT over the period studied.
“Nationwide, there has been a notable decrease in combined modality therapy, especially in clinical trials, many of which are designed to avoid this strategy,” said Rahul Parikh, MD, of Rutgers Cancer Institute of New Jersey in New Brunswick.
“This form of treatment has shown to be effective, with event-free survival rates greater than 80% and overall survival rates greater than 95%. The question then becomes, ‘does treatment benefit outweigh the risk of long-term side effects?”
With this in mind, Dr. Parikh and his colleagues compared CMT to chemotherapy alone using data from the National Cancer Database spanning the period from 2004 to 2015.
The researchers analyzed 5,657 patients with stage I/II classical HL who had a mean age of 17.1.
Roughly half of patients received CMT (50.3%, n=2845), and the other half received chemotherapy alone (49.7%, n=2812).
The median radiotherapy dose was 21.0 Gy, and the most common modality was photon therapy (59.0%).
Patients who received CMT were significantly more likely to be younger than 16 (P<0.001), be male (P<0.001), have stage II disease (P=0.02), and have private health insurance (P=0.002).
The median follow-up was 5.1 years.
The 5-year OS was 94.5% for patients who received chemotherapy alone and 97.3% for patients treated with CMT.
CMT was significantly associated with improved OS in both univariate (hazard ratio [HR]=0.58, P<0.001) and multivariate analyses (HR=0.57, P<0.001).
In a sensitivity analysis, the researchers found the greatest benefits of CMT were in adolescents and young adults (age 14 and older, adjusted HR=0.47) and patients with low-risk disease (stage I-IIA, adjusted HR=0.59).
The researchers noted that this study was limited by their inability to control for unreported prognostic factors, such as the number of nodal sites and bulk of disease.
Another limitation was the duration of follow-up, which did not allow the researchers to fully assess secondary late effects of CMT and their potential impact on survival.
Still, Dr. Parikh said this study demonstrates a survival benefit for young HL patients treated with CMT.
“With that, physicians should be encouraged to discuss combined modality therapy as one of the many treatment options [for young HL patients],” he said.
“Investigators may also consider designing future clinical trials for this population to include combined modality therapy as a standard arm with the inclusion of interim treatment response assessment (PET scans, etc.). And 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.”
Dr. Parikh and his colleagues declared no conflicts of interest for the current study.