62 Background: Previous studies have reported that breast cancer patients with high stress levels at diagnosis develop more frequent and severe side effects of chemotherapy treatment. However, the relationship between stress and radiotherapy (RT) related treatment toxicity has not been evaluated. We investigated whether baseline stress is associated with worse acute skin toxicity in women undergoing breast RT. Methods: Between March 2010 and April 2013, 80 post-lumpectomy breast cancer patients were enrolled on a prospective study prior to undergoing definitive whole breast RT (50 Gy plus a 10 Gy boost). Prior to RT (baseline), at week 6 of RT (T2), and 6 weeks post RT (T3), subjects completed the Perceived Stress Scale (PSS) and underwent objective ultrasound measurements of epidermal thickness over the lumpectomy cavity and in all four quadrants of the treated breast. A skin thickness ratio (STRA) was generated by normalizing for measurements taken of the untreated breast. RT-induced skin toxicity was assessed by measuring the change in STRA from baseline to T2 and T3. Results: Mean STRA increased by 23% (SD 27%) and 33% (SD 25%) from baseline to T2 and T3, respectively. Univariate analysis revealed PSS score at baseline (p=.04), body mass index (p=.03), maximum RT dose (Dmax) (p=.02) and whole breast volume (p<.001) were significantly associated with increased changes in STRA during RT. Depression, fatigue, race, chemotherapy, patient age, and tumor stage were not associated with changes in STRA. On multivariate analysis, PSS (p=.05), breast volume (p=.004), and Caucasian race (p=.04) were associated with greater acute changes in STRA from baseline to T2. Breast volume (p=.01), but not PSS, predicted for greater changes in STRA 6 weeks after RT was completed. Conclusions: In women with breast cancer, a high level of perceived stress prior to RT is associated with more severe acute skin toxicity during RT but not after RT is completed. Strategies to reduce stress prior to RT may improve tolerance of treatment.
Evaluation of acute skin toxicity during radiotherapy for breast cancer in elderly patients
