What are the recommended staging investigations for breast cancer?

Staging Investigations for Breast Cancer

For early-stage breast cancer (Stage I-II), routine distant metastasis screening with bone scans, chest imaging, and abdominal imaging is not recommended in asymptomatic patients, as the yield is extremely low and does not improve outcomes. 1

Essential Baseline Workup for All Patients

All newly diagnosed breast cancer patients require the following core assessments:

• Clinical evaluation: Complete personal and family history, physical examination including assessment of menopausal status 1
• Laboratory tests: Complete blood count, liver and renal function tests, alkaline phosphatase, and calcium levels 1
• Breast imaging: Bilateral mammography and ultrasound of breasts and regional lymph nodes 1
• Pathological diagnosis: Core needle biopsy (preferably ultrasound or stereotactic-guided) to confirm invasive disease 1
• Biomarker assessment: ER, PR, HER2 status, and proliferation markers (Ki67) from biopsy specimen 1
• Lymph node evaluation: Clinical examination and ultrasound, with ultrasound-guided fine needle aspiration or core biopsy of suspicious nodes 1

MRI Indications (Selective Use Only)

Breast MRI is not routinely recommended but should be considered in specific situations 1:

• BRCA mutation carriers or familial breast cancer
• Breast implants present
• Lobular cancers
• Suspected multifocality/multicentricity
• Large discrepancies between conventional imaging and clinical examination
• Before and during neoadjuvant chemotherapy 1

Important caveat: MRI has high false-positive rates (7.8-33.3% alter surgical plans without proven outcome benefit), and patients should not be denied breast-conserving therapy based on MRI findings alone without tissue confirmation 1

Distant Metastasis Staging: Risk-Stratified Approach

Low-Risk Patients (Stage I, Stage II with ≤3 positive nodes)

Do NOT perform routine distant staging investigations 1:

• Bone scans detect metastases in only 0.5% of Stage I and 2.4% of Stage II patients 2
• Liver imaging detects metastases in 0% of Stage I and 0.4% of Stage II patients 2
• Chest imaging detects metastases in 0.1% of Stage I and 0.2% of Stage II patients 2
• The false-positive rates (10-66%) far exceed true-positive rates, leading to unnecessary anxiety and additional testing 2

High-Risk Patients Requiring Full Staging

Chest CT, abdominal imaging (ultrasound, CT, or MRI), and bone scan should be performed for patients with 1:

• Clinically positive axillary nodes
• Large tumors (≥5 cm)
• Aggressive tumor biology
• Clinical signs, symptoms, or laboratory abnormalities suggesting metastases 1
• Stage III disease (T3N1M0, T4, or N2) 1

Evidence basis: Metastasis detection rates increase substantially in high-risk groups—bone scan positivity rises from 0.5% in Stage I to 8.3-14% in Stage III disease 3, 2

Role of PET-CT

• Not recommended for routine staging of early breast cancer due to high false-negative rates for small (<1 cm) or low-grade lesions and poor sensitivity for axillary nodes 1
• May be useful when conventional imaging is inconclusive or for high-risk patients (locally advanced/inflammatory disease) who are candidates for neoadjuvant chemotherapy 1
• Less sensitive for lobular cancers and low-grade tumors 1

Cardiac Function Assessment

Mandatory cardiac ultrasound or MUGA scan before starting anthracyclines and/or trastuzumab 1

Genetic Testing Indications

Offer BRCA1/BRCA2 testing to patients with 1:

• Strong family history of breast, ovarian, pancreatic, or high-grade/metastatic prostate cancer
• Breast cancer diagnosis before age 50
• Triple-negative breast cancer before age 60
• Personal history of ovarian cancer, second breast cancer, or male sex

Common Pitfalls to Avoid

• Over-staging early disease: The American College of Radiology confirms no survival benefit from intensive surveillance imaging in asymptomatic Stage I patients 1
• Relying on tumor markers: Routine tumor marker testing (CEA, CA 15.3) is not recommended for staging as it does not improve outcomes 1
• Ordering PET scans reflexively: NCCN explicitly recommends against PET/PET-CT for early-stage disease due to low sensitivity and high false-positive rates 1
• Incomplete biomarker testing: If ER/PR/HER2 are negative on biopsy, retest on surgical specimen to account for tumor heterogeneity 1

Postoperative Pathological Assessment

The surgical specimen must be evaluated according to pTNM system including 1:

• Number, location, and maximum diameter of tumors
• Total number of removed and positive lymph nodes with extent of metastases (isolated tumor cells, micrometastases 0.2-2 mm, macrometastases)
• Histological type and grade
• Resection margin status with minimum distance
• Vascular invasion
• Biomarker analysis confirmation