- One-quarter of patients undergoing radiation treatment for locally advanced NSCLC receive a mean heart dose exceeding 20 Gy, a level linked to cardiac event rates ≥20% at 2 years.
Why this matters
- Ionizing radiation dose to the heart during NSCLC treatment is strongly associated with inferior survival; treatment approaches are needed that meet dose constraints without compromising disease management goals.
- Researchers studied patients with stage 3 NSCLC treated with radiation within a statewide consortium of 22 oncology clinics (N=746; mean age, 67 years; 54% men; left-sided primary disease, 38%; N2/N3 disease, 80%).
- They surveyed sites within the consortium to assess established dose constraints.
- Funding: Blue Cross Blue Shield of Michigan; Blue Care Network.
- Median mean heart dose was 12 Gy (interquartile range, 5-19 Gy).
- Percentage of heart volume exceeding a 30-Gy dose threshold (V30Gy) was >50% in 5% of cases; V40Gy was >35% in 3% of cases.
- 16 (89%) of 18 responding clinics used cardiac dose constraints, but none was consistently applied across the consortium.
- V30Gy was the most common dose level, used by 80% of clinics; the most common threshold was V30Gy≤50%.
- No clinic used low dose constraints (
- Lack of cardiac morbidity, cardiac mortality, and overall survival outcomes preclude strong recommendations on specific dose constraints.