In a health-related quality-of-life study reported in The Lancet Oncology, King et al found that adjuvant radiotherapy with a tumor bed boost was associated with poorer cosmetic status and arm and shoulder functional status than radiotherapy with no boost among women with non–low-risk ductal carcinoma in situ (DCIS) undergoing breast-conserving surgery.
The study included 1,208 women with completely excised DCIS randomly assigned between June 2007 and August 2013 to receive a tumor bed boost (n = 603) vs no boost (n = 605) following conventional whole-breast radiotherapy or hypofractionated whole-breast radiotherapy according to three separate randomization categories. Time to local recurrence—the primary endpoint of the trial—is to be reported when patients have completed 5 years of follow-up.
The current analysis reports health-related quality-of-life findings for eight prespecified outcomes at 6, 12, and 24 months after radiotherapy:
Analyses were performed in the intention-to-treat population, with Hochberg adjustment used for multiple testing. Comparisons were expressed as effect sizes for the difference between tumor bed boost and no boost groups.
Health-related quality-of-life assessments were completed by 95% of patients at baseline and 87% at 2 years.
Tumor bed boost was associated with worse cosmetic status at all time points (effect size difference = 0.10, global P = .00014, Hochberg adjusted P = .0016). Poorer outcome was observed at the end of treatment (difference = 0.13, P = .00021) and persisted at 24 months (difference = 0.13, P = .00021).
Tumor bed boost was also associated with worse arm and shoulder function across all time points (difference = 0.08, global P = .0033, Hochberg adjusted P = .045). Poorer outcome was observed at the end of treatment (difference = 0.08, P = .021) but not at 24 months (difference = 0.04, P = .29).
No differences in fatigue, physical functioning, breast-specific symptoms, body image, sexuality, or perceived risk of invasive breast cancer between the tumor bed boost vs no tumor bed boost groups were observed after adjustment for multiple testing.
Conventional whole-breast radiotherapy was associated with poorer body image vs hypofractionated whole-breast radiotherapy at the end of treatment (difference = –1.10, P = .0016), with no significant differences between conventional whole breast radiotherapy vs hypofractionated whole breast radiotherapy being observed for other outcomes.
The investigators concluded: “Tumor bed boost was associated with persistent adverse effects on cosmetic status and arm and shoulder functional status, which might inform shared decision-making while local recurrence analysis is pending.”
Madeleine T. King, PhD, of The University of Sydney, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funding by the National Health and Medical Research Council, Susan G. Komen for the Cure, Breast Cancer Now, OncoSuisse, and Dutch Cancer Society. For full disclosures of the study authors, visit thelancet.com.