Standard Surveillance vs. Intensive Surveillance in Early Breast Cancer

Inclusion criteria

• Written informed consent for all study procedures according to local regulatory requirements prior to beginning specific protocol procedures.
• Unilateral or bilateral primary invasive carcinoma of the breast, confirmed histologically.
• Patients with intermediate- to high-risk early breast cancer defined as either
• an indication for (neo-)adjuvant chemotherapy (regardless whether performed or not), and/or
• Large tumor (\> 50 mm), and/or
• Positive lymph nodes, and/or
• High grade (\>= G3). Indication to (neo-)adjuvant chemotherapy is seen as stated in the German S3 guideline for breast cancer as well as stated in the guidelines from the AGO.
• A complete resection of the primary tumor, with resection margins free of invasive carcinoma.
• Completion of primary anti-tumor therapy (adjuvant chemotherapy, surgery or radiotherapy, whichever occurs last) at least 4 weeks but no more than 24 months previously. Enrollment of patients during any kind of adjuvant therapy except chemotherapy (e.g., but not limited to endocrine therapy, antibody therapy, CDK4/6-inhibitors, PARP inhibitors, PI3K inhibitors, antibody-drug conjugates and other novel agents) is allowed.
• Availability of primary tumor tissue from core biopsy or surgical removed tissue (FFPE Slide (≥ 6 mm³, min. 10 slides, thickness: 5 µm-10 µm, area \>150 mm² and 1 H\&E stained slide, minimum 20% tumor content) or FFPE Block (≥ 6 mm³ thickness: 100 µm, area: \>150 mm² and 1 H\&E stained slide, minimum 20% tumor content) or Genomic DNA extracted from FFPE slides or block (≥ 600 ng, Minimum volume: 25 µL, concentration: 20 ng/µL, buffer: 10 mM Tris pH 8, 1 mM EDTA)) at timepoint of enrollment.
• Patients with primary systemic therapy: tissue from core biopsy
• Patients receiving surgery as primary therapy: surgically removed cancer tissue.
• No current clinical evidence for distant metastases.
• Females or males ≥ 18 years and ≤ 75 years of age.
• Performance status ≤ 1, Eastern Cooperative Oncology Group (ECOG) scale.
• Patient must be willing and able to comply with scheduled visits, treatment plans, laboratory tests, and other study procedures.

Exclusion criteria

• Patients with a history of any secondary primary malignancy are ineligible with the following exceptions:
• in situ carcinoma of the cervix or
• adequately treated basal cell carcinoma of the skin or
• ipsi- or contralateral non-invasive carcinoma of the breast (DCIS).
• Patients in pregnancy or breastfeeding. If a patient gets pregnant during the participation in the interventional phase of the study (Year 1-5), an end of intervention visit will be scheduled and the patient will enter the follow-up phase of the study. Pregnancy during the follow-up phase of the study is to be reported but does not lead to an exclusion of the study.
• History of significant neurological or psychiatric disorders including psychotic disorders, dementia or seizures that would prohibit the understanding and giving of informed consent.
• Renal insufficiency with GFR \< 30 mL/min.
• Previous or concomitant cytotoxic or other systemic antineoplastic treatment that is not used for treating the primary breast cancer.