What are the next steps after being newly diagnosed with breast cancer?

Initial Workup After Newly Diagnosed Breast Cancer

For newly diagnosed early-stage breast cancer, order bilateral mammography with breast ultrasound, core needle biopsy for pathological confirmation with biomarker assessment (ER, PR, HER2, Ki67), basic laboratory studies (CBC, comprehensive metabolic panel), and clinical examination—but do NOT routinely order metastatic imaging (CT, bone scan, PET) unless the patient has high tumor burden, aggressive biology, or symptoms suggesting metastases. 1

Essential Diagnostic Testing

Pathological Confirmation

• Obtain core needle biopsy (minimum 2-3 cores) under ultrasound or stereotactic guidance before any treatment begins 1
• Place a surgical clip or carbon marker into the tumor at biopsy to ensure accurate resection later 1
• If multifocal or multicentric disease is suspected, biopsy all lesions 1
• Core biopsy is mandatory if preoperative systemic therapy is planned to confirm invasive disease and assess biomarkers 1

Required Biomarker Assessment

The pathology report must include:

• Estrogen receptor (ER) and progesterone receptor (PR) status by immunohistochemistry 1
• HER2 status (immunohistochemistry and/or in situ hybridization if equivocal) 1
• Histological type and grade according to WHO classification 1
• Ki67 proliferation index 1
• Evaluation of resection margins after surgical excision 2

Imaging Studies

Required imaging:

• Bilateral mammography to evaluate both breasts 1
• Ultrasound of the breast and regional lymph nodes 1
• If suspicious lymph nodes are identified, perform ultrasound-guided fine-needle aspiration or core biopsy with clip marking 1

Consider breast MRI in specific situations:

• BRCA mutation carriers or familial breast cancer 1
• Lobular cancers 1
• Dense breasts 1
• Suspected multifocality/multicentricity 1
• Large discrepancies between conventional imaging and clinical examination 1
• Before neoadjuvant systemic therapy 1
• Occult primary with positive axillary nodes 1

Laboratory Studies

Routine baseline labs include:

• Complete blood count 1, 2
• Comprehensive metabolic panel including liver enzymes, alkaline phosphatase, calcium 1, 2
• Menopausal status verification (if uncertain, measure serum estradiol and FSH) 1

Staging for Metastatic Disease

Critical distinction: The approach differs dramatically based on clinical stage.

For Stage I breast cancer (small tumors, clinically node-negative):

• Do NOT routinely order CT scans, bone scans, or PET-CT 1
• There is no survival benefit from intensive imaging surveillance in asymptomatic early-stage patients 1
• Only order metastatic workup if symptoms suggest distant disease or if high tumor burden/aggressive biology is present 1

For higher-risk disease (Stage II-III, symptomatic, or aggressive features):

• Chest X-ray or CT chest 1, 2
• Abdominal ultrasound or CT abdomen 1, 2
• Bone scintigraphy 1, 2
• Consider brain imaging if symptomatic or in certain high-risk subtypes 1

Additional Genetic and Molecular Testing

Germline Testing

• Evaluate for hereditary cancer syndromes and consider genetic counseling for relatives 1
• Germline BRCA1/2 testing should be considered, particularly for triple-negative breast cancer, young age at diagnosis, or family history 1

Genomic Profiling

• Gene expression profiles (e.g., Oncotype DX, MammaPrint) may provide prognostic and predictive information for ER-positive disease to guide chemotherapy decisions 2
• This is particularly useful for intermediate-risk ER-positive, HER2-negative breast cancer 3

Clinical Assessment

Complete medical history focusing on:

• Personal breast cancer risk factors 1
• Family history of breast, ovarian, and other cancers 1
• Menopausal status 1
• Comorbidities that may affect treatment decisions 1

Physical examination must include:

• Thorough breast examination 1
• Assessment of regional lymph nodes (axillary, supraclavicular, infraclavicular) 1
• General physical examination 1

Common Pitfalls to Avoid

Do not over-stage asymptomatic early-stage patients: The most common error is ordering extensive metastatic workup (CT scans, bone scans, PET-CT) for Stage I breast cancer, which provides no survival benefit and may lead to false positives, unnecessary anxiety, and additional testing 1

Do not perform excisional biopsy first: Core needle biopsy should be obtained before any surgical procedure except in rare cases of repeatedly negative core biopsies 1

Do not delay biomarker assessment: ER, PR, and HER2 status are mandatory before treatment planning and directly determine systemic therapy options 1, 3

Do not skip multidisciplinary review: Treatment planning should involve a team including surgical oncology, medical oncology, radiation oncology, radiology, and pathology specialized in breast cancer 2

Staging System

• Use the TNM staging system (8th edition AJCC) which incorporates both anatomical and biological factors (tumor grade, ER, PR, HER2) 1