This study aims to conduct whole genome sequencing in breast cancer patients to elucidate individual genetic characteristics and their correlation with breast cancer subtypes. The primary objective is to establish new treatment guidelines aligned with the paradigm shift in precision medicine. The study will include both prospective and retrospective cohorts totaling 1200 participants. Prospective participants must provide consent and be eligible for tissue collection, while retrospective participants must have histologically confirmed breast cancer and available tissue samples from Samsung Medical Center Biobank. The study period spans 3 years for subject enrollment and 5 years for follow-up observations, with an expected completion date of December 31, 2030.

Breast cancer is a complex disease with diverse genetic characteristics, necessitating personalized treatment approaches. This study proposes to conduct whole genome sequencing (WGS) to comprehensively analyze the genetic landscape of breast cancer patients, aiming to identify novel genetic alterations and their implications for disease classification and treatment response.

The primary objective of this research is to elucidate the individual genetic profiles of breast cancer patients through WGS and subsequent analysis. By characterizing the genomic alterations unique to each patient, this study seeks to refine breast cancer subtyping, facilitate the discovery of innovative treatment strategies, and optimize therapeutic decision-making.

This multicenter study will enroll a total of 1200 participants, comprising both prospective and retrospective cohorts. Prospective participants will be recruited based on specific inclusion criteria, including age, consent for tissue collection, and histologically confirmed breast cancer diagnosis. Retrospective participants will be identified from existing breast cancer tissue samples collected between 2012 and 2023 and stored in the Samsung Medical Center Biobank.

The study will involve comprehensive data collection, including clinical, pathological, and genomic information. Participants will undergo WGS analysis of tumor samples, and the resulting genomic data will be correlated with clinical outcomes to identify potential prognostic markers and therapeutic targets.

The research will be conducted under the supervision of Professor Yeonhee Park, an expert in hematology-oncology at Samsung Medical Center, in collaboration with Inocras Inc, the study sponsor. The study period will span three years for subject enrollment, followed by a five-year follow-up observation period. The expected completion date for the study is December 31, 2030.

This study holds the potential to significantly advance our understanding of the molecular basis of breast cancer and pave the way for the development of personalized treatment approaches tailored to individual patients' genetic profiles.

[Prospective study]

Inclusion Criteria:

• Patients who have consented to both the patient consent form and the consent for the use of human-derived materials.
• Patients who are aged 19 years or older at the time of signing the consent form.
• Patients capable of providing written consent to participate voluntarily in the study.
• Patients eligible for tissue examination and surgical removal to facilitate sample collection.
• Patients histologically confirmed with breast cancer or undergoing tissue examination for pathological confirmation due to imaging findings suggestive of breast cancer.

Exclusion Criteria:

• Patients who do not understand or refuse to consent in writing.
• Patients for whom obtaining sufficient samples is challenging.
• Patients who refuse genetic testing.

[Retrospective study]

Inclusion Criteria:

• Patients histologically confirmed with breast cancer.
• Patients for whom breast cancer tissues collected between 2012 and 2023 are stored in the Samsung Seoul Hospital Biobank and available for distribution.

Exclusion Criteria:

- Patients for whom sufficient tissue for analysis is not adequately stored.

Prospective study : 500 Retrospective study : 700