Evaluating Minimal Residual Disease (MRD) Through Longitudinal Circulating Tumor DNA (ctDNA) Profiling in Breast Malignancies

Inclusion criteria

All Cohorts:

• Willing and able to participate in the research and provide biospecimens
• Willing and able to provide informed consent
• Must be diagnosed with breast cancer

Cohort 1: Neoadjuvant Treatment Cohort 1A: Newly Diagnosed, High Risk HR+,HER2-

• A known or suspected HR+, HER2- breast cancer treated with curative intent (Stage II to III disease)
• Patients are considered at high risk of recurrence, defined as 4 or more positive axillary lymph nodes (ALNs), or between 1-3 positive ALNs and either grade 3 disease or tumor size of 5 cm or larger.

Cohort 1B: HER2+ 1. A known or suspected HER2+ breast cancer treated with curative intent (Stage II to III disease). Inclusive of HR+ or HR- patients.

Cohort 1C: Triple Negative Breast Cancer

• A known or suspected triple negative breast cancer treated with curative intent (Stage I to III disease).

Cohort 2: Adjuvant Therapy / Surveillance Cohort 2A: Newly Diagnosed HR+,HER2-

• A known or suspected HR+, HER2- breast cancer treated with curative intent (Stage II to III disease)
• Patients are considered at high risk of recurrence, defined as 4 or more positive axillary lymph nodes (ALNs), or between 1-3 positive ALNs and either grade 3 disease or tumor size of 5 cm or larger.
• Have undergone curative intent surgery with no clinical evidence of disease.

Cohort 2B: HER2+

• A known or suspected HER2+ breast cancer treated with curative intent (Stage II to III disease)
• Have undergone curative intent surgery with no clinical evidence of disease.

Cohort 2C: Triple Negative Breast Cancer

• A known or suspected triple negative breast cancer treated with curative intent (Stage I to III disease)
• Have undergone curative intent surgery with no clinical evidence of disease.

Cohort 3: 5-Years Post-Diagnosis Surveillance (NED)

• A known HR+, HER2- breast cancer treated with curative intent (Stage II to III disease).
• No Evidence of Disease (NED) ≥ 5 years from initial diagnosis.
• Patients are considered at high risk of recurrence, defined as 4 or more positive axillary lymph nodes (ALNs), or between 1-3 positive ALNs and either grade 3 disease or tumor size of 5 cm or larger.

Exclusion criteria

• Not willing or able to adhere with the study procedures
• Active secondary malignancy
• Diagnosis of a malignancy within 3 years of breast cancer diagnosis Note: Ductal carcinoma in situ (DCIS, ipsilateral or contralateral) within 3 years is not excluded.