Is radiation-induced cardiac toxicity reversible? Prospective evaluation of breast cancer patients enrolled in a phase-III randomized controlled trial
Abstract
OBJECTIVES
Myocardial perfusion defects after breast radiotherapy (RT) correlates with volume of irradiated left ventricle (LV). We aimed to determine the relationship between myocardial perfusion, LV dosimetry, and grade ≥2 latent cardiac events (LCE) in breast cancer (BC) patients undergoing adjuvant RT.
METHODS
A randomized study evaluated the benefit of inverse-planned intensity modulated radiotherapy (IMRT) over forward-planned IMRT for radiation toxicity in breast cancer. A secondary end-point was evaluation of cardiac perfusion by single-photon emission computed tomography (SPECT) done at baseline, 6 months and 1, 2 and 5 years post RT. Receiver Operating Curve and regression analysis were done to identify association between perfusion, radiation dose-volumes and the risk of LCE.
RESULTS
Of 181 patients that received adjuvant RT, 102 were left-sided and 79 were right breast cancer patients. Median follow-up was 127 months (19-160 months). A significant worsening of perfusion defects occurred post-RT in the left-sided group which improved by 1 year. LCE were 16(17.2%) in left-sided and 4(5.5%) in the right-sided groups respectively. Perfusion changes did not correlate with LCE, but LV dose-volumes correlated with LCE. Maintaining the LV volume receiving 5Gy and 10 Gy to <42cc and <38cc respectively, can reduce the risk of radiation related late cardiac events at 10 years to <5% over baseline.
CONCLUSIONS AND RELEVANCE
RT was associated with short-term perfusion defects…
How strong is the evidence?
Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design. Reported size: 181 participants or records.
Read the paper
Related studies
- Preliminary Toxicity Analysis of 3DCRT versus IMRT on the High Dose Arm of the RTOG 0126 Prostate Cancer Trial
- Adaptive Radiotherapy for Head and Neck Cancer: Initial Clinical Outcomes from a Prospective Trial
- American Association of Physicists in Medicine Task Group 263: Standardizing Nomenclatures in Radiation Oncology
- Motion Management Strategies and Technical Issues Associated with Stereotactic Body Radiotherapy of Thoracic and Upper Abdominal Tumors: A Review from NRG Oncology
- High-dose-rate interstitial brachytherapy as a monotherapy for localized prostate cancer: treatment description and preliminary results of a phase I/II clinical trial
- Highly efficient training, refinement, and validation of a knowledge-based plan quality control system for radiotherapy clinical trials
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.