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

Author(s): Rachel B. Jimenez, MD¹; Yara Abdou, MD²; Penny Anderson, MD³; Parul Barry, MD⁴; Lisa Bradfield, BA⁵; Julie A. Bradley, MD⁶; Lourdes D. Heras, MPH⁷; Atif Khan, MD, MS⁸; Cindy Matsen, MD⁹; Rachel Rabinovitch, MD¹⁰; Chantal Reyna, MD, MHA¹¹; Kilian E. Salerno, MD¹²; Sarah E. Schellhorn, MD¹³; Deborah Schofield, PhD¹⁴; Kekoa Taparra, MD, PhD, MPH¹⁵; Iman Washington, MD¹⁶; Jean L. Wright, MD¹⁷; Youssef H. Zeidan, MD, PhD¹⁸; Richard C. Zellars, MD¹⁹; Kathleen C. Horst, MD²⁰;

Source: DOI: 10.1200/JCO-25-01747

Dr. Maen Hussein's Thoughts

Guidelines for post-mastectomy radiation include patients who received neoadjuvant therapy, with or without residual disease after treatment. A good topic to review.

PURPOSE

This guideline provides recommendations on use of postmastectomy radiation therapy (PMRT) in breast cancer treatment. Updated recommendations detail indications for PMRT in the upfront surgical setting and after neoadjuvant systemic therapy, and provide guidance on appropriate target volumes, dosing, and treatment techniques.

METHODS

A multidisciplinary American Society for Radiation Oncology–ASCO–Society of Surgical Oncology task force addressed four key radiation therapy (RT) questions in patients with breast cancer who undergo mastectomy: (1) indications for PMRT after upfront surgery, (2) indications for PMRT after neoadjuvant systemic therapy followed by surgery, (3) appropriate PMRT volumes and dose-fractionation regimens, and (4) treatment techniques. Recommendations were based on a systematic review and created using a predefined consensus-building methodology for quality of evidence grading and strength of recommendation.

RECOMMENDATIONS

After upfront mastectomy, PMRT is indicated for most patients with node-positive breast cancer and select patients with node-negative disease. PMRT is also recommended after neoadjuvant systemic therapy for patients presenting with locally advanced disease and for those with residual nodal disease the time of surgery. PMRT is conditionally recommended for patients with cT1-3N1 or cT3N0 breast cancer with pathologically negative nodes after neoadjuvant systemic therapy (ypN0). When PMRT is delivered, treatment to the ipsilateral chest wall or reconstructed breast and regional lymphatics is recommended, with moderate hypofractionation preferred, but with conventional fractionation approaches acceptable in rare cases. Computed tomography–based volumetric treatment planning with 3-dimensional conformal RT is recommended, with intensity-modulated RT advised when three-dimensional conformal RT is unable to achieve treatment goals. Deep inspiration breath-hold techniques are also recommended for normal tissue sparing. For patients with skin involvement, positive superficial margins, and/or lymphovascular invasion, use of a bolus is recommended, but routine use of tissue-equivalent bolus is not recommended.Additional information is available www.asco.org/breast-cancer-guidelines.

Author Affiliations

¹Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA; ²Department of Medical Oncology, University of North Carolina, Chapel Hill, NC; ³Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA; ⁴Department of Radiation Oncology, UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA; ⁵American Society for Radiation Oncology, Arlington, VA; ⁶Department of Radiation Oncology, University of Florida, Jacksonville, FL; ⁷Patient Representative, Surviving Breast Cancer, Gilbert, AZ; ⁸Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY; ⁹Department of Surgery, Huntsman Cancer Institute the University of Utah, Salt Lake City, UT; ¹⁰Department of Radiation Oncology, University of Colorado Denver, Aurora, CO; ¹¹Department of Surgery, Loyola University Medical Center, Chicago, IL; ¹²Radiation Oncology Branch, National Cancer Institute, Bethesda, MD; ¹³Department of Medicine, Yale School of Medicine, New Haven, CT; ¹⁴Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX; ¹⁵Department of Radiation Oncology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA; ¹⁶Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL; ¹⁷Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC; ¹⁸Department of Radiation Oncology, Florida International University and Lynn Cancer Institute, Boca Raton, FL; ¹⁹Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN; ²⁰Department of Radiation Oncology, Stanford University, Stanford, CA

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