Breast Cancer
It's most commonly an Invasive Adenocarcinoma, and the types of this are:
Ductal carcinoma (75%)
Lobular carcinoma (15%)
The risk factors for it include:
Increased lifetime oestrogen exposure
Increasing age
Early menarche, Late menopause, Long-term COCP/HRT
Obesity - peripheral conversion of androgens to oestrogen
Family Hx
BRCA1/2 mutations
P53 mutations (Li-Fraumeni syndrome)
Alcohol and tobacco use
N.B. Women with BRCA mutations are also at high risk of ovarian ca., so a prophylactic b/l mastectomy/salpingo-oopherectomy is considered.
N.B. In men, BRCA2 mutations is associated with Prostate cancer (also pancreatic and gastric cancers).
Presentation:
Hard, painless lump
Nipple retraction
Skin dimpling
Swollen axillary lymph nodes
Ulceration
Peau d’orange - Skin dimpling or oedema
Investigated with a triple assessment - clinical, imaging, histology.
Ductal Carcinoma (75%)
This is an abnormal proliferation of ductal cells. It has metastatic potential as there’s invasion through the basement membrane. If there was no invasion of the basement membrane, it would called a Ductal carcinoma in situ (DCIS), which is a pre-cancer.
N.B. Invasive cancer grows through the ductal epithelium and fixes to deeper tissues → immobile mass. DCIS doesn’t invade → mobile mass.
Lobular Carcinoma (15%)
This is an abnormal proliferation of lobular cells, which arrange themselves in single rows. The tumour cells are sparsely distributed, so they’re frequently impalpable or not felt as a discrete lump.
If there was no invasion of the basement membrane, it would called a Lobular carcinoma in situ (LCIS), which is a pre-cancer.
NHS Breast Screening Programme
The aim of this is to detect DCIS and any small, early-stage invasive carcinomas.
It includes a Mammogram every 3 yrs for women 50-70 years , looking for microcalcifications.
Prognostic Factors
The most important prognostic factor is the Sentinel Lymph node. This is the first node that a cancer drains into. To check it, a dye is injected into the tissue around the tumour and the nodes that take up the dye are assessed visually with a probe. If the nodes are found +ve for cancer, the patient is given a full axillary clearance (surgical removal of the nodes).
Other prognostic factors include:
Tumour Stage + Grade
Histological subtype
Invasion
Completeness of excision
ER and HER2 Status
Oestrogen receptors (ER) - Negative indicates a worse prognosis
HER2 - Positive indicates a worse prognosis
N.B. HER2 promotes the growth of cancer cells. It tends to be more aggressive than other types of breast cancer, but it may respond well to targeted therapies that block HER2.
Management
Surgical options:
Wide local excision (WLE) or Mastectomy
Axillary node clearance if sentinal node +ve for cancer
ER+ve tumours:
Tamoxifen (ER antagonist) if premenopausal
SEs - Hot flushes, Nausea, PV bleeding, VTE, Endometrial ca.
Anastrozole (aromatase inhibitor) if postmenopausal
SEs - Hypo-oestrogenism (hot flushes, fatigue, osteoporosis)
N.B. Post-menopausal women have low oestrogen, so most of it will be made from its conversion via aromatase. This is why antagonists to this enzyme is more beneficial in these women.
HER2 +ve tumours:
Herceptin (Trastuzumab - monoclonal antibody)
SEs - Cardiac dysfunction, Teratogenicity

