title: Racial variations in radiation-induced skin toxicity severity: data from a prospective cohort receiving postmastectomy radiation.
abstract: OBJECTIVE
  Radiation-induced skin toxicity is one of the most symptomatic side effects of postmastectomy radiation therapy (PMRT). We sought to determine whether the severity of acute skin toxicity was greater in black patients in a prospective cohort receiving PMRT and to identify other predictors of more severe skin toxicity.
  
  
  METHODS
  We evaluated the first 110 patients in an ongoing prospective study assessing radiation-induced skin toxicity in patients receiving PMRT. We recorded patient demographics, body mass index (BMI), and disease and treatment characteristics. Logistic regression analyses were conducted to evaluate the effect of potential predictors on the risk of skin toxicity.
  
  
  RESULTS
  A total of 23.6% respondents self-identified as black, 5.5% as non-Hispanic white, 69.1% as Hispanic white, and 1.8% as other; 57% were postmenopausal, and 70.9% had BMI of >25. Median chest wall dose was 50 Gy, and mastectomy scar dose was 60 Gy. Most patients, 95.5%, were treated with a 0.5-cm bolus throughout treatment. There were no significant differences in patient characteristics in black versus non-black patients. At RT completion, moist desquamation was more common in black patients (73.1% vs 47.6%, respectively, P=.023), in postmenopausal patients (63.5% vs 40.4%, respectively, P=.016), and in those with BMI of ≥25 (60.3% vs 37.5%, respectively, P=.030). On multivariate analysis, the effects of black race (odds ratio [OR] = 7.46, P=.031), BMI ≥25 (OR = 2.95, P=.043) and postmenopausal status (OR = 8.26, P=.004) remained significant risk factors for moist desquamation.
  
  
  CONCLUSIONS
  In this prospectively followed, racially diverse cohort of breast cancer patients receiving PMRT delivered in a uniform fashion, including the routine use of chest wall boost and bolus, black race, higher BMI, and postmenopausal status emerged as significant predictors of moist desquamation. There was a high frequency of moist desquamation, particularly in those patients with elevated risk. Continued study of patient selection for chest wall boost and bolus as well improved skin toxicity management strategies are needed.
authors.affiliation: Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland. Electronic address: jwrigh71@jhmi.edu.
authors.forename: Jean L
authors.initials: JL
authors.lastname: Wright
authors.affiliation: Department of Radiation Oncology, University of Miami Sylvester Comprehensive Cancer Center, Miami, Florida.
authors.forename: Cristiane
authors.initials: C
authors.lastname: Takita
authors.affiliation: Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida; Department of Public Health Sciences, University of Miami, Miami, Florida.
authors.forename: Isildinha M
authors.initials: IM
authors.lastname: Reis
authors.affiliation: Department of Public Health Sciences, University of Miami, Miami, Florida.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Department of Public Health Sciences, University of Miami, Miami, Florida.
authors.forename: Eunkyung
authors.initials: E
authors.lastname: Lee
authors.affiliation: Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida; Department of Public Health Sciences, University of Miami, Miami, Florida.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Hu
mesh_terms: D000328:Adult; D000368:Aged; D044383:Black People; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000208:ethnology / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D017698:Postmenopause; D011446:Prospective Studies; D011855:Radiodermatitis / Q000208:ethnology* / Q000473:pathology; D012044:Regression Analysis; D044465:White People