Breast Cancer Flashcards
What is the most common cancer in the UK, what is the lifetime risk, and in what age does it most commonly occur?
- Breast cancer
- 1 in 8 for women in the UK
- 40-70 years of age
What are the risk factors for developing breast cancer?
- Increasing lifetime oestrogen exposure
- Female sex
- Increasing age
- Obesity - peripheral aromatisation of androgens to oestrogens
- Early menarche, late menopause
- Long term COCP, HRT >10 years.
- Nulliparous
- Family history (5-10% familial)
What is the genetic trait responsible for some breast cancers and how is it inherited?
- Germline BRCA1 and BRCA2 (tumour suppressor genes) mutation account for 85% of familial breast cancers.
- Autosomal dominant
What is there a risk of developing with the BRCA1 and BRCA2 gene mutations?
- 85-100% lifetime risk of breast cancer
2. High risk of ovarian cancer as well
What prophylactic treatment is provided if a patient is identified to have the BRCA1 or BRCA2 gene mutation?
Bilateral mastectomy and salpingo-oophrectomy
What is this a presentation of?
Usually upper, outer quadrant of breast. Hard, painless lump, may be fixed to chest wall/skin. Nipple inversion and skin dimpling.
Breast cancer
What conditions is breast cancer associated with?
- Ulceration/fungation
- Peau d’orange
- Nipple eczema in Paget’s disease
- Palpable axillary lymph nodes
- Metastatic disease (weight loss, pleural effusions)
How is a suspected breast cancer investigated?
- Triple assessment
- Graded and staged
- MDT discussion
What type of cancer are almost all malignant breast tumours?
Adenocarcinoma:
- Ductal carcinoma (75%)
- Lobular carcinoma (10-15%)
What is ductal carcinoma in situ?
Epithelial cells show cytological changes of malignancy. However, basement membrane is intact and the cells have not invaded surrounding tissue. Significant proportion progress to invasive ductal carcinoma.
What is ductal carcinoma in situ associated with on mammography and how is it treated?
- Microcalcifications
2. Surgical excision
What is Paget’s disease of the nipple?
Disease affecting the skin of the nipple and areola due to the presence of ductal carcinoma in situ cells in the epidermis.
What is the appearance of the skin in Paget’s disease of the nipple?
Eczematous
How does Paget’s disease of the nipple prgress?
DCIS cells extend along the major ducts and reach the nipple where it enters deeper layers of the epidermis. Still does not invade basement membrane so is not a cancer.
What is the pathophysiology of invasive lobular carcinoma?
Composed of tumour cells which infiltrate the normal breast tissue as linear cords of cells. This discohesive the pattern is a reflection of loss of function of the E-cadherin-catenin cell adhesion system.
What is the most important prognostic factor in breast cancer?
TNM staging - lymph node status in particular
What are the prognostic factors in breast cancer?
- Stage - TNM
- Grade - 3-tier system
- Histological subtype
- Vascular invasion
- Excision margins
- Oestrogen receptor and HER2 status
What are the features of an oestrogen receptor positive breast cancer and how is it treated?
- Low grade and less aggressive
2. Responds to hormonal therapy - tamoxifen in pre/peri-menopausal women, aromatase inhibitors in post-menopausal women
What are the features of an oestrogen receptor negative breast cancer?
Tend to be higher grade and more aggressive
What is HER2 and what is it associated with?
- Oncogene that encodes transmembrane tyrosine kinase receptor, overexpressed in 15% of invasive breast cancers.
- Poorer prognosis, good response to Herceptin (monoclonal Ab against HER2)
What is a sentinel lymph node?
The first lymph node draining a cancer
What is the process of identifying an affected sentinel lymph node in breast cancer?
Dye and/or isotope injected around tumour, visual inspection for staining, gamma probe for isotope.
What is done if a sentinel node is positive in breast cancer?
Axillary clearance - removal of all axillary lymph nodes
What is the NHS breast screening programme and what does it aim to identify?
- All women aged 50-70 invited for screening mammogram every 3 years.
- If suspicious features are detected, called back for further assessment.
- Aim to identify ductal carcinoma in situ.
What is the name of the isotope used in identifying an affected sentinel lymph node in breast cancer?
Technetium-99