The objectives of this study are:

1. To determine the difference in genetic profiling of subjects with breast cancer recurrence
2. To determine the comprehensive genetic profiling of subjects with late stage breast cancer
3. To determine the potential biomarkers for early detection and prognosis for breast cancer
4. To determine the genetic profiling of immune system in different subtypes of breast cancer

By integrating and analyzing the data generated using the methods of NGS, these information can be used for:

1. Understanding the genetic profiling of different subtypes of breast cancer in Taiwan
2. Assessing the efficacy of different treatments in breast cancer subjects
3. Defining the molecular risk factors and predicting the potential risk of breast cancer recurrence
4. Assessing the immune repertoire and the potential effects of immunotherapy in breast cancer subjects
5. Developing new strategies in treating patients with triple negative or late stage of breast cancer

Inclusion Criteria:

• Female subjects aged over 20 years old

• Subject with confirmed diagnosis of primary invasive breast cancer and is planning to receive treatments for breast cancer. However, subjects with breast cancer recurrence at screening will be enrolled if meet both the following conditions:

  1. Subjects had received surgery for primary breast cancer within 3 years prior to screening [i.e. recurrence within 3 years after surgery (mastectomy or BCS)];
  2. Subjects diagnosed with stage IV breast cancer beyond 3 years after surgery (mastectomy or BCS) or who had received or are currently receiving treatments for breast cancer. And subjects with primary tumor FFPE tissues available and pass the RNA quality check.

• Eastern Cooperative Oncology Group (ECOG) Performance score ≤ 3

• Life expectancy ≥ 3 months

• Subject agrees to provide the written informed consent. If a subject has breast cancer recurrence within 3 years prior to screening, she will be eligible if she agrees to provide the paired FFPE tissues (primary and recurrent tumors)

Exclusion Criteria:

• Subjects will be excluded if they had primary cancer other than breast cancer within 5 years prior to screening

Subject with confirmed diagnosis of primary invasive breast cancer and is planning to receive treatments for breast cancer.