Development of Patient Derived Xenografts (PDX) in Patients With Breast Cancer

Development of Patient Derived Xenografts (PDX) in Patients With Breast Cancer Who Have Residual Disease After Neoadjuvant Systemic Therapy

Breast cancer patients who undergo neoadjuvant systemic therapy and have residual breast cancer identified at the time of surgery exhibit a high (>50%) risk of future life-threatening recurrences and death.

This study is being done to collect blood and leftover surgical tissue from patients with breast cancer remaining after chemotherapy or endocrine therapy is completed. We will use the blood and tissue for future studies. These studies will try to find ways to treat future breast cancer patients.

Because there is cancer left in your body after breast cancer treatment is finished, we think the cancer may be different than other cancers. Tissue from surgery will be used to try to grow that kind of cancer in the lab so we can find out more about it and how to treat it.

Blood samples will be used to look at measurements of biomarkers to see how this cancer is different and seek new ways to identify and treat it.

Inclusion Criteria:

• Age ≥18 years.

• Diagnosis of invasive breast cancer treated with neoadjuvant systemic therapy.

• Surgically resectable disease following neoadjuvant systemic treatment.

• At least one of the following must be true:

  • Received at least 2 weeks of neoadjuvant endocrine therapy
  • Received at least 2 months of neoadjuvant chemotherapy with suggestion of residual disease on imaging
  • Began neoadjuvant chemotherapy or endocrine therapy but discontinued due to evidence of progressive disease by MRI, ultrasound, or physical examination

• Provide written informed consent.

• Willing to return to enrolling institution for breast cancer surgery.

• Willingness to provide mandatory blood specimens for future research on breast cancer at Mayo Clinic.

• Willingness to provide mandatory tissue specimens for future research on breast cancer at Mayo Clinic.

• Willingness to provide mandatory tissue specimens for the generation of PDX and organoids to be used future research on breast cancer at Mayo Clinic.

Exclusion Criteria:

• Ineligible for surgery.
• History of prior malignancy <3 years prior to registration. Exceptions for non-melanoma skin cancer, papillary thyroid cancer, non-invasive cancer (e.g., carcinoma in situ of the cervix).