A recent study published online by Journal of Clinical Oncology found race-related differences in breast pain in patients with breast cancer who received whole-breast radiotherapy in addition to substantial differences according to radiotherapy dose fractionation (2020. doi:10.1200/JCO.20.01703).
Reshma Jagsi, MD, Dphil, University of Michigan (Ann Arbor, MI) and colleagues evaluated patient-reported outcomes prospectively collected from a cohort of patients with breast cancer. The population included those with the maximal toxicity reported by 8711 patients treated between 2012 and 2019 at 27 practices. Characteristics associated with (1) breast pain; (2) bother from itching, stinging/burning, swelling, or hurting of the treated breast; and (3) fatigue within 7 days of completing whole-breast radiotherapy were identified by multivariable models.
According to their findings, 3,233 (37.1%) reported moderate or severe breast pain: 1282 (28.9%) of those received hypofractionation and 1951 (45.7%) of those received conventional fractionation. Frequent bother from at least one breast symptom was reported by 4424 (50.8%): 1833 (41.3%) after hypofractionation and 2591 (60.7%) after conventional fractionation. Severe fatigue was reported by 2008 (23.1%): 843 (19.0%) after hypofractionation and 1165 (27.3%) after conventional fractionation.
In patients receiving hypofractionated radiotherapy, younger age (P < .001), higher body mass index (BMI; P < .001), Black (P < .001) or other race (P = .002), smoking status (P < .001), larger breast volume (P = .002), lack of chemotherapy receipt (P = .004), receipt of boost treatment (P < .001), and treatment at a nonteaching center predicted breast pain.
Younger age (P < .001), higher BMI (P = .003), Black (P < .001) or other race (P = .002), diabetes (P = .001), smoking status (P < .001), and larger breast volume (P < .001) predicted breast pain among patients receiving conventionally fractionated radiotherapy.
Ultimately, Dr Jagsi and colleagues found that “substantial differences existed according to radiotherapy dose fractionation.” Moreover, “race-related differences in pain existed despite controlling for multiple other factors.”
Authors think further research is needed to understand what drives these differences, so that clinicians can then target modifiable factors. For example, “intensifying supportive care may be appropriate for subgroups identified as being vulnerable to greater toxicity,” they said. A better understanding of acute toxicities after whole-breast radiotherapy is needed to more effectively inform patients, guide care decisions, and target appropriate supportive care.—Amanda Del Signore
