The risk of radiation-related cardiovascular disease (CVD) may be low for most patients with early-stage Hodgkin lymphoma (HL), according to research published in the Journal of Clinical Oncology.
The researchers analyzed data from the RAPID trial (ClinicalTrials.gov Identifier: NCT00943423), which was designed to determine whether patients with stage IA or IIA HL require consolidation radiotherapy after 3 courses of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD).
The study included patients who were PET-negative or PET-positive after ABVD. Patients in both groups were randomly assigned to involved-field radiotherapy (IFRT) — 30 Gy in daily fractions of 1.8 Gy to 2.0 Gy — or no further treatment.
The current analysis included 144 PET-negative patients who received IFRT. The mean heart dose received was 4.0 Gy (range, 0.1-24.0 Gy).
The average predicted 30-year risk of developing CVD was 35.8% for these patients. The researchers noted that the expected risk of CVD, based on rates in the general population, was 22.9%. So IFRT conferred an excess risk of 6.2%, and ABVD conferred an excess risk of 6.7%.
The absolute excess risk of CVD from IFRT was dominated by ischemic heart disease (3.28%) and stroke (2.31%), the researchers noted.
The average predicted 30-year CVD mortality risk was 5.02% for the patient group. This consisted of the 3.52% expected risk based on general population rates, a 0.94% absolute excess risk from ABVD, and a 0.56% excess risk from IFRT.
The absolute excess risk of CVD mortality from IFRT was also dominated by ischemic heart disease (0.36%) and stroke (0.14%).
These results suggest that, for most PET-negative patients in this trial, “the predicted cardiovascular risks are small,” the researchers wrote.
“The decision to give radiotherapy for early-stage Hodgkin lymphoma should be patient-specific, based on individualized risk predictions of dose to critical structures and of all the late effects of these exposures,” they added.
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Cutter DJ, Ramroth J, Diez P, et al. Predicted risks of cardiovascular disease following chemotherapy and radiotherapy in the UK NCRI RAPID trial of positron emission tomography–directed therapy for early-stage Hodgkin lymphoma. J Clin Oncol. Published August 13, 2021. doi: 10.1200/JCO.21.00408.