title: Changes in arm tissue composition with slowly progressive weight-lifting among women with breast cancer-related lymphedema.
abstract: BACKGROUND
  Studies in breast cancer-related lymphedema (BRCL) have exclusively examined total arm volume, but not the specific tissue composition that contributes to total volume. We evaluated baseline differences in arm tissue composition [fat mass, lean mass, bone mineral content (BMC), and bone mineral density (BMD)] between the affected and unaffected arms in women with BRCL. We compared changes in arm tissue composition and self-reported lymphedema symptoms after 1 year of weight-lifting versus control.
  
  
  METHODS
  We utilized data from physical activity and lymphedema trial that included 141 women with BRCL. Arm tissue composition was quantified using dual-energy X-ray absorptiometry. The severity of lymphedema was quantified using self-report survey. Weight-lifting was performed at community fitness facilities.
  
  
  RESULTS
  At baseline, the affected arm had more fat (∆ = 89.7 g; P < 0.001) and lean mass (∆ = 149.1 g; P < 0.001), but less BMC (∆ = -3.2 g; P < 0.001) and less BMD (∆ = -5.5 mg/cm2; P = 0.04) than the unaffected arm. After 12 months of weight-lifting, composition of the affected arm was improved: lean mass (71.2 g; P = 0.01) and BMD (14.0 mg/cm2; P = 0.02) increased, arm fat percentage decreased (-1.5%; P = 0.003). Composition of the unaffected arm was only improved in lean mass (65.2 g; P = 0·04). Increases in lean mass were associated with less severe BCRL symptoms.
  
  
  CONCLUSIONS
  Among women with BRCL, slowly progressive weight-lifting could improve arm tissue composition. Changes in arm tissue composition predict changes in symptom burden. Investigating the combined effects of exercise and weight loss on arm tissue composition and BCRL symptoms may provide additional insight into the benefits of lifestyle modification on lymphedema biology.
authors.affiliation: Public Health Science, Penn State College of Medicine, Penn State Cancer Institute, Room T3427, 500 University Drive, Mail code CH69, Hershey, PA, 17033, USA.
authors.forename: Xiaochen
authors.identifier: http://orcid.org/0000-0003-3086-1285
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Division of Population Sciences, Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Brown
authors.affiliation: Division of Cancer Prevention and Control, Department of INTERNAL Medicine, College of Medicine, The Ohio State University, Columbus, OH, USA.
authors.forename: Electra D
authors.initials: ED
authors.lastname: Paskett
authors.affiliation: Clinical and Translational Research Center, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Babette S
authors.initials: BS
authors.lastname: Zemel
authors.affiliation: Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Cheville
authors.affiliation: Public Health Science, Penn State College of Medicine, Penn State Cancer Institute, Room T3427, 500 University Drive, Mail code CH69, Hershey, PA, 17033, USA. kschmitz@phs.psu.edu.
authors.forename: Kathryn H
authors.initials: KH
authors.lastname: Schmitz
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D001132:Arm / Q000503:physiopathology*; D001823:Body Composition; D015519:Bone Density / Q000502:physiology; D001943:Breast Neoplasms / Q000150:complications / Q000503:physiopathology*; D015444:Exercise; D005260:Female; D006801:Humans; D008019:Life Style; D008209:Lymphedema / Q000150:complications / Q000503:physiopathology*; D014891:Weight Lifting
keywords: Lymphedema; Physical activity; Survivorship; Tissue composition