This is a randomized, double-blinded trial of self-acupressure to examine the effect of treatment on aromatase inhibitor (AI)-associated musculoskeletal symptoms (AIMSS) in postmenopausal women with breast cancer. Acupressure is similar to acupuncture, but uses pressure rather than needles to stimulate specific points on the body. Acupressure involves applying mild to moderate physical pressure using your fingers, or an assistive device, to these points to try to bring about a physiological change in your body, in this case relief from joint pain and stiffness. The investigators will also examine effects of acupressure on other symptoms that commonly develop in AI-treated patients. In addition, changes in stool microbiome with acupressure treatment will be examined in an exploratory way to obtain preliminary information about the effect of acupressure on the gut microbiome in this condition.

Inclusion Criteria:

• Female or male subject aged ≥ 18 years
• Taking the currently prescribed aromatase inhibitor therapy (anastrozole, exemestane, or letrozole) for adjuvant or palliative treatment of breast cancer or for chemoprevention for at least 3 weeks and no more than 2 years at the time of enrollment.
• Planning to take the same AI therapy for at least 12 weeks.
• New or worsening joint pain and/or myalgias since starting the AI therapy, with worst pain score of at least 4 out of 10 on the BPI over the 7 days prior to enrollment.
• Completion of radiation therapy, if given, for treatment of breast cancer.
• Completion of chemotherapy, if given. Concurrent use of LHRHa therapy, anti-HER2 therapy, bisphosphonate therapy, PARP inhibitor therapy, and CDK4/6 inhibitor therapy is permitted.
• Patients receiving treatment with NSAIDs, acetaminophen, opioids, duloxetine, cannabinoids, gabapentin, and/or pregabalin must have been taking a stable dose for at least 30 days prior to enrollment if they plan to continue the drug during study participation. If they do not plan to take the medication during study participation, they should stop the medication at least 7 days before initiation of study treatment.
• Able to self-complete questionnaires in English.
• Able to access WiFi/internet and willing to use an email account or download and use the MyDataHelps app.
• Able to provide informed consent and willing to sign an approved consent form that conforms to federal and institutional guidelines.

Exclusion Criteria:

• Use of acupuncture or acupressure in the past year, or planned use of acupuncture during study participation.
• Use of systemic or transdermal estrogen during study participation.
• Planned surgery during the 12-week study period.
• Concurrent medical or arthritis disease such as painful bone metastases or active rheumatoid arthritis or inflammatory arthritis that could confound or interfere with evaluation of pain or efficacy. Patients with osteoarthritis and asymptomatic bone metastases are eligible.
• Patients with a prior or concurrent malignancy whose natural history or treatment, in the opinion of the treating investigator, has the potential to interfere with the safety or efficacy assessment of the investigational regimen.

participant demographics and patient-reported outcomes data will be available to researchers upon reasonable request

researchers can request data once the primary analysis has been published

deidentified data will be available to researchers upon reasonable request

Both clinicians and participants will be blinded to study arm.