Clinical Scorecard: Advancing Precision Cardio-Oncology in Breast Cancer Radiotherapy

At a Glance

Key Highlights

• Left-sided radiotherapy is associated with a higher risk of ischemic heart disease (IHD) compared to right-sided treatment in women with multiple cardiovascular risk factors.

• The 8-year cumulative incidence of IHD was 20.3% for left-sided versus 15.2% for right-sided treatment.

• A 6-item cardiovascular risk burden score includes age, obesity, smoking, hypertension, diabetes, and dyslipidemia.

• Treatment planning should be individualized based on absolute cardiovascular risk rather than laterality alone.

• Concurrent management of cardiometabolic risk factors is essential for patients undergoing left-sided breast cancer radiotherapy.

Guideline-Based Recommendations

Diagnosis

• Assess cardiovascular risk factors prior to radiotherapy planning.

Management

• Implement cardiac-sparing radiotherapy planning for patients with multiple cardiovascular risk factors.

Monitoring & Follow-up

• Ongoing assessment of cardiovascular health and risk factor control during survivorship.

Risks

• Increased risk of IHD associated with left-sided radiotherapy, particularly in patients with multiple cardiovascular risk factors.

Patient & Prescribing Data

Women with breast cancer undergoing postoperative radiotherapy.

Cardiac-sparing techniques and concurrent management of cardiovascular risk factors may mitigate risks.

Clinical Best Practices

• Utilize a multidisciplinary approach involving oncology and cardiology for treatment planning.

• Consider advanced treatment planning techniques such as intensity-modulated radiotherapy and proton therapy.

• Encourage lifestyle modifications and management of cardiovascular risk factors in breast cancer survivors.

Related Resources & Content

1. Chung and Noh, JAMA Network Open, 2026 -- Laterality of Breast Radiotherapy and Ischemic Heart Disease by Cardiovascular Risk Burden

2. American Heart Association, PubMed, 2026 -- Coronary Atherosclerosis in Patients With Cancer and Survivors: A Scientific Statement

3. ASTRO, PubMed, 2026 -- Dose-Volume Histogram Compendium of Dose Constraints for Treatment Planning

4. ASTRO-ASCO-SSO, PubMed, 2026 -- Postmastectomy Radiation Therapy: An ASTRO-ASCO-SSO Clinical Practice Guideline

5. the asco post — Cardio-Oncology Is a Growing Subspecialty, but Where Are the Oncologists?

6. the asco post — Accelerated Radiation Therapies Move Forward in Early Breast Cancer

7. The ASCO Post — Reducing Incidental Cardiac Irradiation during Breast Radiotherapy

8. The ASCO Post — Breast Cancer Radiotherapy Leads to Moderate Cardiac Function Decline Over Years

9. Cardio-Oncology Is a Growing Subspecialty, but Where Are the Oncologists?

10. Accelerated Radiation Therapies Move Forward in Early Breast Cancer

11. Reducing Incidental Cardiac Irradiation during Breast Radiotherapy

12. Coronary Atherosclerosis in Patients With Cancer and Survivors: A Scientific Statement From the American Heart Association - PubMed

13. Dose-Volume Histogram Compendium of Dose Constraints for Treatment Planning: An ASTRO Consensus Paper - PubMed

14. Postmastectomy Radiation Therapy: An ASTRO-ASCO-SSO Clinical Practice Guideline - PubMed

15. Concurrent Versus Sequential Radiation Dose Escalation to the Surgical Cavity for Conservative Treatment of High-Risk Early Breast Cancer: NRG/RTOG 1005 Phase III Trial | Journal of Clinical Oncology

16. Deep inspiration breath hold versus free breathing in postoperative radiotherapy strategy for patients with left-sided breast cancer treated with volumetric modulated arc therapy: A meta-analysis and systematic review - PubMed

17. Laterality of Breast Radiotherapy and Ischemic Heart Disease by Cardiovascular Risk Burden | Oncology | JAMA Network Open | JAMA Network