Hypofractionation of Breast Radiotherapy Associated With Reduced Acute Toxicity


Key Points

  • Hypofractionation was associated with significantly reduced acute skin reactions and self-reported pain, burning/stinging, hurting and swelling bother, and fatigue.
  • Conventional fractionation was associated with slightly greater absence of skin induration during follow-up, but there were no other longer-term differences between groups.

In an analysis reported in JAMA Oncology, Jagsi et al found that hypofractionation of whole-breast radiotherapy was associated with reduced acute toxicity compared with conventional fractionation.

Study Details

The study involved data on physician-assessed toxic effects and patient-reported outcomes in 2,309 patients who received adjuvant whole-breast radiotherapy after lumpectomy for unilateral breast cancer at Michigan Radiation Oncology Quality Consortium sites from October 2011 through June 2014. Patients had to have a comprehensive physician toxicity evaluation within 1 week of completing radiotherapy and at least 1 weekly evaluation during treatment.

Toxic effects in patients receiving hypofractionation vs conventional fractionation were compared during treatment (through 7 days after treatment) and in follow-up (post-treatment days 8–210). Physicians reported common toxic effects at baseline, weekly during radiotherapy, and in follow-up. Consenting patients rated their own experiences, including breast pain, fatigue, and being bothered by symptoms.

Reduced Acute Toxicity

Of the 2,309 evaluable patients, 1,731 received conventional fractionation and 578 received hypofractionation; of these, 1,297 and 426 provided self-reported ratings. After adjustment for sociodemographic, clinical, and treatment factors, patients receiving conventional fractionation had significantly higher maximum physician-assessed skin reaction (moist desquamation = 28.5% vs 6.6%, P < .001; grade ≥ 2 dermatitis = 62.6% vs 27.4%, P < .001) and self-reported pain (moderate/severe pain = 41.1% vs 24.2%, P = .003), burning/stinging bother (often/always = 38.7% vs 15.7%, P = .002), hurting bother (33.5% vs 16.0%, P = .001), swelling bother (29.6% vs 15.7%, P = .03), and fatigue (29.7% vs 18.9%, P = .02) during treatment. The conventional fractionation group had a higher rate of absence of skin induration during follow-up (84.5% vs 81.2%, P = .02). There were no significant differences in any other outcomes during follow-up through 6 months.

The investigators concluded: “Hypofractionation not only improves convenience but also may reduce acute pain, fatigue, and the extent to which patients are bothered by dermatitis in patients with breast cancer undergoing whole-breast radiotherapy.”

Reshma Jagsi, MD, DPhil, of University of Michigan Medical School, is the corresponding author for the JAMA Oncology article.

Funding for MROQC is provided by Blue Cross Blue Shield of Michigan and Blue Care Network.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.