PATHCHAT Edition No. 52
January 2019
Please contact your local Ampath pathologist for more information.
Authors:
- Dr. Carolyn Fedler (Chemical Pathologist)
- Dr. Piet Swanepoel (Anatomical Pathologist)
Breast Cancer Overview
✅ Key Facts:
- Most common potentially fatal invasive cancer in women.
- 100 times more common in women than in men.
- Higher incidence in first-world countries but increasing in developing regions.
- Western lifestyle factors (high fat/alcohol intake, smoking, oral contraceptives, delayed childbirth) contribute to rising incidence.
📌 Prognosis depends on cancer type and stage, with early diagnosis leading to significantly higher survival rates.
Breast Cancer Survival Rates by Stage
✔ Stage 0: 99–100%
✔ Stage I: 95–100%
✔ Stage II: 86%
✔ Stage III: 57%
✔ Stage IV: 20%
📌 Early detection and treatment significantly improve survival rates.
Risk Factors for Breast Cancer
✅ 1. Age:
- Risk increases with age, especially after 30.
- Early-onset cancers tend to be more aggressive.
✅ 2. Hormonal Factors:
- Early menarche (<12 years) and late menopause (>55 years).
- Nulliparity (never giving birth) and non-breastfeeding.
✅ 3. Lifestyle Factors:
- High-fat diet, high alcohol consumption.
- Obesity: Women who gain weight over time have almost double the risk.
- Smoking (active & passive): Increases risk by 15–40%.
- Radiation exposure.
✅ 4. Breast Changes & History:
- Proliferative breast disease (atypical ductal hyperplasia, in situ carcinoma).
- Previous history of breast cancer increases the risk for the second breast.
✅ 5. Family History & Genetics:
- Higher risk if a close relative (mother, sister, daughter) has had breast or ovarian cancer.
- Carriers of BRCA1 or BRCA2 mutations have a high lifetime risk.
- Other potential genetic mutations: p53, PTEN.
📌 Women with a strong family history may benefit from genetic testing and increased screening.
BRCA Testing & Genetic Risk Assessment
✅ Key Considerations for BRCA Testing:
- Not all individuals with a family history are equally at risk.
- Pre-test counselling is essential to discuss limitations and implications.
- Post-test counselling helps patients understand specific mutations and associated risks.
- BRCA testing should include full gene sequencing when possible.
✅ BRCA Testing in South Africa:
- Available in major laboratories.
- Ensure whether “hot spot” testing or full sequencing is performed.
📌 BRCA testing is only one part of genetic risk assessment; regular screening remains essential.
Signs & Symptoms of Breast Cancer
✅ Common Symptoms:
- Lump or thickening in the breast (not all lumps are malignant).
- Swelling, skin dimpling, redness, or soreness.
- Changes in nipple shape or appearance (inversion, discharge).
📌 Early breast cancer may not present with palpable lumps and is best detected via mammography.
Breast Cancer Prevention Strategies
✅ Ways to Reduce Risk:
- Maintain a healthy weight and increase physical activity.
- Limit alcohol consumption.
- Breastfeed infants when possible.
- Consider prophylactic mastectomy in high-risk BRCA mutation carriers.
📌 Lifestyle changes can significantly reduce breast cancer risk.
Screening, Detection & Diagnosis
✅ Recommended Screening Tests:
- Breast self-examination.
- Clinical breast examination.
- Mammography (recommended annually after 40).
- Ultrasound (useful for dense breast tissue).
- Breast MRI (for high-risk patients).
- PET scans (advanced imaging for metastases).
✅ Diagnostic Procedures:
- Fine Needle Aspiration (FNA).
- Core Needle Biopsy.
- Sentinel Lymph Node Biopsy (preferred over axillary dissection).
📌 Early detection through routine screening greatly improves treatment outcomes.
Role of Pathology in Breast Cancer
✅ 1. Histopathology:
- Classifies tumours as ductal, lobular, or other variants.
- Differentiates carcinoma in situ from invasive cancer.
✅ 2. Tumour Grading:
- Grade 1 (Well-differentiated): Better prognosis.
- Grade 2 (Moderately differentiated).
- Grade 3 (Poorly differentiated): Worse prognosis.
✅ 3. Staging (TNM System):
- Stage 0: Pre-cancerous or in situ carcinoma.
- Stages 1–3: Tumour within breast or regional lymph nodes.
- Stage 4: Metastatic cancer (e.g., spread to bones or brain).
✅ 4. Receptor Status Testing:
- Oestrogen receptor (ER), progesterone receptor (PR), HER-2 status.
- ER+ tumours respond to hormonal therapy (e.g., tamoxifen).
- HER-2+ tumours benefit from targeted therapy (e.g., trastuzumab).
📌 Receptor testing guides treatment selection and prognosis.
Treatment Options
✅ Individualized treatment based on:
- Tumour size, stage, and receptor status.
🔹 1. Surgery:
- Lumpectomy (breast-conserving surgery).
- Mastectomy (total removal of the breast).
- Sentinel lymph node biopsy or axillary dissection for staging.
🔹 2. Radiation Therapy:
- Destroys residual cancer cells after surgery.
🔹 3. Hormonal Therapy:
- Selective Estrogen Receptor Modulators (SERMs) (e.g., Tamoxifen).
- Aromatase inhibitors (e.g., Anastrozole) for postmenopausal women.
🔹 4. Chemotherapy:
- Used for aggressive or advanced-stage cancers.
🔹 5. Targeted Therapy:
- HER-2 inhibitors (e.g., Trastuzumab) for HER-2 positive cancers.
📌 Treatment plans are customized based on tumour characteristics and patient factors.
Emerging Molecular & Genetic Testing
✅ DNA Microarrays & Gene Expression Profiling:
- Tests like OncotypeDx & MammaPrint analyze gene clusters to guide treatment decisions.
- Available in North America & Europe; Mammaprint is available in South Africa at Stellenbosch University.
📌 Gene expression assays help predict recurrence risk and treatment response.
Key Takeaways for Clinicians
✅ Breast cancer is the most common invasive cancer in women, with rising global incidence.
✅ Early detection via mammography, clinical exams, and genetic testing improves survival rates.
✅ BRCA testing should be considered in high-risk individuals but does not replace routine screening.
✅ Tumour grading, staging, and receptor profiling guide treatment selection.
✅ Molecular testing (Mammaprint, OncotypeDx) may refine treatment decisions in selected cases.
📌 Individualized treatment plans based on tumour biology provide the best outcomes for breast cancer patients.