Transcranial Direct Current Stimulation to Improve Gait for Breast Cancer Survivor's Who Received Taxene and/or Platinum Chemotherapy

• Sham Intervention (Procedure), also known as sham (procedure), Sham Comparator: Receive sham tDCS
• Survey Administration (Other): Ancillary studies
• Transcranial Direct Current Stimulation (Device), also known as tDCS: Receive tDCS

Primary outcomes

• Dual task gait speed cost [Before and after stimulation at visit 2 and 3]: This cost will be operationalized as the absolute and percent change in gait metrics (time to walk/variability) during dual-task walking relative to walking without a secondary task. Cost will be defined as (\[speed dual task - speed single task\]/speed single task\] *100). Will fit a series of linear mixed models with each of the dual task costs, prefrontal cortex activation, and executive function measures as the dependent variables; sequence, period, and treatment as fixed effects of interest; baseline values as fixed effect covariates; and a participant-within sequence random effect.

Secondary outcomes

• Dual task cost to gait speed [At baseline]: Will fit a series of analyses of covariance models with each gait single task and dual-task cost measure as the dependent variable; group (older, taxane-treated female breast cancer survivors versus non-cancer historical control group) as the factor of interest; and other measures of interest (age, proprioception, grip strength, depression, and pain) or other variables different between groups as covariates.
• Prefrontal hemodynamic response [At baseline]: Assessed via functional near-infrared spectroscopy during dual task gait speed. Will fit a series of linear mixed models with each measure of prefrontal cortex activation as the dependent variable; group (older, taxane-treated female breast cancer survivors versus non-cancer historical control group), task (single/dual), and their interaction as fixed effects; covariates as additional fixed effects; and a participant random effect.

Sex: Female, ages: 60 Years to 85 Years

Inclusion Criteria:

* Women aged 60-85 years
* Breast cancer survivors, stages I-IV without clinical suspicion or evidence of brain metastasis
* Completion of last taxane and/or platinum chemotherapy treatment ≥ 6 months prior, but chemotherapy was received after the age of 60. Taxane combined with a history of platinum, anthracycline and/or cyclophosphamide is permitted. Active anti-estrogen therapy, Anti-HER2, and CDK 4/6 inhibitors are permitted
* Ability to walk unassisted for 60 seconds
* Proficient in English
* Without neurological disease, aside from chemotherapy induced peripheral neuropathy (CIPN) or chemotherapy related cognitive dysfunction (CRCD)
* No history of a second cancer besides skin cancer

Exclusion Criteria:

* Hospitalization within the past three months due to acute illness or as the result of a musculoskeletal injury significantly affecting gait or balance
* Any unstable medical condition
* Diagnosis of a gait disorder, Parkinson's disease, Alzheimer's disease or dementia, multiple sclerosis, previous stroke or other neurodegenerative disorder
* Chronic vertigo
* Myocardial infarction within the past six months
* History of immune check point inhibitor therapy
* Any history of brain or cervical spine surgery, known hearing, visual, or vestibular impairment
* Active neurotoxic chemotherapy (taxane, platinum or vinca alkaloid) or radiation therapy
* Contraindications to transcranial direct simulation (tDCS), including reported seizure within the past two years,, metal objects in head or neck, self-reported presence of specific implanted medical devices (e.g., deep brain stimulator, cochlear implant, vagus nerve stimulator, spinal cord stimulator, pacemakers, and intracardiac devices, etc.), or the presence of any active dermatological condition, such as eczema, on the scalp

• Brendan L McNeish, Principal investigator, University of Michigan Rogel Cancer Center

NIH grants: K23AG090624