A study by Ganz et al assessed quality-of-life outcomes following whole- or partial-breast radiation in patients with breast cancer who underwent lumpectomy. The researchers published their findings in the Journal of the National Cancer Institute.
Study Methods and Results
In the NRG Oncology NRG/NSABP B-39/RTOG 0413 clinical trial, researchers compared outcomes following whole-breast irradiation with those following accelerated partial-breast irradiation among 4,210 patients with stage 0, I, or II breast cancer resected by lumpectomy. The patients had a tumor size ≤ 3.0 cm and had no more than three histologically positive nodes.
The researchers sought to determine whether partial-breast irradiation limited to the region of the tumor bed following lumpectomy provided equivalent local tumor control in the breast compared with conventional whole-breast irradiation in the local management of early-stage breast cancer. The secondary outcome for the trial was quality of life. The researchers determined that accelerated partial-breast irradiation was not statistically equivalent to whole-breast irradiation in local tumor control.
The quality-of-life substudy provided an in-depth evaluation of fatigue and treatment toxicities using well-established patient-reported outcome measures. With a target accrual of 964 patients—482 with clinician intent to prescribe chemotherapy and 482 without clinician intent—the substudy used validated self-report questionnaires like the Breast Cancer Treatment Outcome Scale and the SF-36 vitality scale. Assessments occurred prior to randomization; at completion of chemotherapy or radiotherapy; 4 weeks following treatment; and at 6, 12, 24, and 36 months. The primary aims for the substudy were cosmesis change equivalency and fatigue change superiority for accelerated partial-breast irradiation vs whole-breast irradiation, according to patient groups treated with or without chemotherapy.
The researchers found that the cosmetic outcomes were comparable between the accelerated partial-breast irradiation and whole-breast irradiation groups, with small statistically significant differences in other outcomes that varied over time. Differences in fatigue and other symptoms appeared to resolve by ≥ 6 months. Accelerated partial-breast irradiation may be preferred by some patients, for whom extended treatment is burdensome.
Conclusions
“Partial- and whole-breast radiation have equivalent cosmetic outcomes at 3 years postlumpectomy in [patients with] breast cancer, but significantly greater end-of-treatment fatigue occurred in patients receiving whole-breast irradiation after lumpectomy without chemotherapy,” concluded lead study author Patricia Ganz, MD, of the University of California, Los Angeles.
Disclosure: The research in this study was supported by grants from the National Cancer Institute of the National Institutes of Health. For full disclosures of the study authors, visit academic.oup.com.
