Women’s Health - New Breast (mainly cancer) Flashcards
How common is breast cancer
Breast cancer is the most common form of cancer in the UK. It mostly affects women and is rare in men (about 1% of UK cases). Around 1 in 8 women will develop breast cancer in their lifetime.
56,000 new cases annually
Basic breast anatomy
The breast is made up of the following main components:
Most of the breast is adipose (fatty) tissue.
Lobules are part of the glandular system; they are glands that produce breast milk. Lobules are found in groups which together form a lobe.
Ducts are small tubes that carry breast milk from the lobules to the nipple.
Breast cancers most commonly arise in the ducts that transport milk from the lobules to the nipple. These are known as ductal cancers. Some breast cancers can develop in the lobules, which are known as lobular cancers.
Risk factors for breast cancer
Age- biggest risk factor
Female (99% of breast cancers)
Increased oestrogen exposure (earlier onset of periods and later menopause)
More dense breast tissue (more glandular tissue)
Obesity
Smoking
Family history (first-degree relatives)
COCP - oestrogen again.
HRT - oestrogen stimualtes proliferation of the breast epithelium. Women should be on the lowest dose of HRT for the shortest period of time to get them over the worst symptoms of menopause
What is ductal carcinoma in situ and how does it differ from invasive carcinoma histologically and behavoirally?
DCIS is pre-invasive disease and a pre-curor to invasive breast cancer. It involves neoplastic proliferation of epithelial cells - confined to duct without
invasion through basement membrane.
Most DCIS cases are completely asymptomatic and are detected
by breast screening - microcalcifications on mammography, but occasionally it can present as a lump. The lining epithelium of the breast ducts becomes thickened as the cells proliferate and eventually appear full of cells, often with central necrosis. Cytologically the cells appear malignant but they have not yet acquired the ability to invade the basement membrane and therefore cannot metastasise. Treatment primarily involves wide excision and radiotherapy
or rarely mastectomy if the disease is more extensive.
LCIS - The other type of pre-invasive breast cancer is lobular carcinoma in situ. This is where there is neoplastic ploriferation of epithelial cells that is confined to the terminal ductal lobular units.
What is invasive breast cancer and what are the different histological types
Invasive carcinoma means that the cells have penetration through basement membrane. There are two common histological types of invasive breast cancer –
ductal (70%) and lobular (10%).
- Invasive ductal carcinoma (commonest - 75%). Neoplastic proliferation of epithelial cells that invades through the ductal basement membrane.
- Invasive lobular carcinoma - harder to feel, less likely to be visible on mammography, more diffuse and therefore more difficult to excise and more prone to be bilateral or multi-focal.
Rarer subtypes include **tubular, mucinous **and medullary but
the treatment is largely the same regardless. Tubular and mucinous
tumours tend to be grade 1 (better differentiated) and therefore have a
better prognosis than the more usual types. **Medullary may be of high
grade. **Other rare subtypes include phyllodes tumour, spindle cell
tumours, primary breast sarcomas and lymphomas of the breast.
**INVASIVE/MALIGNANT BREAST CANCER (80%) IS DIFFERENT FROM METASTATIC BREAST CANCER (25% of cases - spread to other organs) **
What is padget’s disease of the nipple
- This is an eczematous change of the nipple (Erythematous, scaly rash) due to an underlying malignancy (invasive or in-situ).
- should be suspected in apparent nipple eczema that does not resolve with two weeks of steroid/anti fungal cream.
- Indicates breast cancer involving the nipple, may represent DCIS or invasive breast cancer
- Requires biopsy, staging and treatment, as with any other invasive breast cancer
What are the BRCA genes and on what chromosomes are they found.
BRCA refers to the BReast CAncer gene. The BRCA genes are tumour suppressor genes. Mutations in these genes lead to an increased risk of breast cancer (as well as ovarian and other cancers).
mnemonic - 1+2 = 3, 17+13 = 30
The BRCA1 gene is on chromosome 17. In patients with a faulty gene:
Around 70% will develop breast cancer by aged 80
Around 50% will develop ovarian cancer
Also increased risk of bowel and prostate cancer
The BRCA2 gene is on chromosome 13. In patients with a faulty gene:
Around 60% will develop breast cancer by aged 80
Around 20% will develop ovarian cancer
There are other rarer genetic abnormalities associated with breast cancer (e.g., TP53 and PTEN genes).
What is the UK breast cancer screening programme?
Aim of the screening programme?
Minor point but some key downsides to screening
**The NHS breast cancer screening program offers a mammogram every 3 years to women aged 50 – 70 years.
**
Screening aims to detect breast cancer early, which improves outcomes. Roughly 1 in 100 women are diagnosed with breast cancer after going for a mammogram.
There are some potential downsides to screening:
Overdiagnosis - Unnecessary further tests or treatment of cancers would never caused symptoms in the womans lifetume.
Anxiety and stress
Exposure to radiation, with a very small risk of causing breast cancer
Missing cancer, leading to false reassurance
Generally, the benefits far outweigh the downsides and breast cancer screening is recommended.
Who is considered high risk for developing breast cancer and what is their management ?
The following patients are considered high risk and should be referred to secondary care:
A first-degree relative with breast cancer under 40 years
A first-degree male relative with breast cancer
A first-degree relative with bilateral breast cancer, first diagnosed under 50 years
Two first-degree relatives with breast cancer
Management:
- Patients require genetic counselling and genetic testing
- annual mamograms, potentially starting from age 30
- Chemoprevention may be offered for high risk women - Both reduced oestrogen - Tamoxifen if premenopausal and Anastrozole (aromatase inibitor) if postmenopausal (except with severe osteoporosis)
- Risk-reducing bilateral mastectomy or bilateral oophorectomy (removing the ovaries) is an option for women at high risk. This is suitable for only a small number of women and requires significant counselling and weighing up risks and benefits.
KEY - Once a patient has been referred for specialist services under a two week wait referral for suspected breast cancer usually for a breast lump. How are they assessed for breast cancer?
They should initially receive a triple diagnostic assessment comprising of:
Clinical assessment (history and examination)
Imaging (ultrasound or mammography)
Biopsy (fine needle aspiration or core biopsy)
Presentation of breast cancer
Clinical features that may suggest breast cancer are:
Lumps that are hard, irregular, painless or fixed in place (fixed means tethered to the skin or the chest wall)
Nipple retraction
Skin dimpling or oedema (peau d’orange)
Lymphadenopathy, particularly in the axilla
What imaging can be used to investigate breast lumps. What is involved and when is each suitable.
Ultrasound scans cannot be used as a screening tool but can be used to assess lumps in younger women (e.g., under 40 years). They are helpful in distinguishing solid lumps (e.g., fibroadenoma or cancer) from cystic (fluid-filled) lumps.
Mammograms are used as both a screening tool and an investigation for lumps. They are generally more effective in older women - below the age of 40, but remember screening starts at 50 (or for women on HRT) the breast tissue is usually too dense to pick up any cancer and therefore they are less useful. They can pick up calcifications missed by ultrasound.
The breast is compressed in 2 planes, the first is cranio-caudal (CC) with the plates horizontal. This view gives a good image of the medial part of the breast and the deeper part near the chest wall. The second view is with the breast squeezed obliquely, the medio-lateral oblique, (MLO) view. This gives a better view of the axillary tail and
lateral breast.
MRI scans may be used:
- For screening in women at higher risk of developing breast cancer (e.g., strong family history)
- To further assess the size and features of a tumour
How are breast lumps biopsied?
Core Biopsy - under local anaesthetic and ultrasound guidance, a needle mounted to a spring loaded biopsy gun removes an apple core of tissue from the lump.
Formerly fine needle aspiration cytology was used - lower sensitivity and specificity - cytology but not histology (looks at aspirated cells not sections of tissues).
Investigations for axillary lymph node involvement and management in breast cancer
Women diagnosed with breast cancer require an assessment to see if cancer has spread to the lymph nodes (up to 40% of women with breast cancer will have cancer in their axillary nodes at diagnosis) . All women are offered an ultrasound of the axilla (armpit) and ultrasound-guided biopsy of any abnormal nodes.
If no cancer is seen, a sentinel lymph node biopsy may be used during breast cancer surgery where the initial ultrasound does not show any abnormal nodes to confirm that the nodes are clear. 25% of cases the nodes seem normal on ultrasound but cancer is detected on histology after sentinel node biopsy.
If the USS scan/SNB does show signs of cancer in the nodes then full ANC is the management.
SO THE KEY BIT TO MEMORISE IS EVERYONE GETS AN USS. Positive -> ANC, negative ->
The purpose of surgery to the axillary lymph nodes is twofold. It aims to remove any breast cancer deposits within the glands and so provide local disease control and also to provide valuable prognostic information which will determine whether any additional or
adjuvant treatments are needed post-operatively.
Sentinel Lymph Node Biopsy:
Sentinel node biopsy is performed during breast surgery for cancer. An isotope contrast (technitium) and a blue dye are injected into the tumour area. The contrast and dye travel through the lymphatics to the first lymph node (the sentinel node). The first node in the drainage of the tumour area shows up blue and on the isotope scanner. These first nodes are removed and sent for histology to determine if the axilla is involved.
ANC:
If a women if known to have axillary invovlement from USS or from sentinal node biopsy then Axillary node clearance surgery is usually performed. Axillary clearance involves removal of all of the lymph nodes in the axilla. This has a low rate of axillary recurrence (good local control and prognostic information) but can lead to seroma, nerve damage and lymphoma.
Radiotherapy:
Some women with low risk axillary disease are offered radiotherapy to the axilla instead of surgical management.
What 3 receptors are targetted in breast cancer therapy
Breast cancer cells may have receptors that can be targeted with breast cancer treatments. These receptors are tested for on samples of the tumour and help guide treatment. There are three types of receptors:
Oestrogen receptors (ER)
Progesterone receptors (PR)
Human epidermal growth factor (HER2) - Rx with trastuzumab
Triple-negative breast cancer is where the breast cancer cells do not express any of these three receptors. This carries a worse prognosis, as it limits the treatment options for targeting the cancer.