BREAST Flashcards
Where do we find the surface anatomy of the breasts?
They extend horizontally from the lateral border of the sternum to the mid-axillary line and vertically from the 2nd to 6th costal cartilages
What muscles does breast tissue lie on top of?
Pectoralis major and serratus anterior
What are the 2 regions of the breast?
Circular body
Axillary tail - runs along the inferior lateral edge of the pectoralis major towards the axillary fossa
What surrounds the nipple?
The areola which is the circular dark-colored area of skin surrounding it
What are the glands found in the areola?
Montgomery’s glands - sebaceous glands that lubricate and antibacterial
What are mammary glands?
Modified sweat glands that produce milk - a series of ducts and secretory lobules which consist of many alveoli drained by a single lactiferous duct. These ducts converge at the nipple
What attaches the breast to the dermis and underlying pectoral fascia?
The connective tissue stroma - the fibrous portion condenses to form the suspensory ligaments of Cooper
What does the base of the breast lie on top of?
The pectoral fascia - a flat sheet of connective tissue associated with the pectoralis major muscle
What is the retromammary space?
a loose areolar tissue that separates the breast from the pectoralis major muscle. The retromammary space is often the site of breast implantation due to its location away from key nerves and structures that support the breast.
Whats the blood supply to the medial aspect of the breast?
The internal thoracic artery aka internal mammary artery (branch of subclavian artery)
Whats the blood supply to the lateral part of the breast?
Lateral thoracic and thoracoacromial branches - from auxiliary artery
Lateral mammary branches - originate from posterior intercostal arteries from aorta
Mammary branch - from anterior intercostal artery
What is the venous drainage from the breast?
Axillary and internal thoracic veins
What are the 3 groups of lymph nodes that recieve lymph from breast tissue?
75% axillary nodes
20% parasternal nodes
5% posterior intercostal nodes
Where does lymphatic drainage from the skin go?
drains to the axillary, inferior deep cervical and infraclavicular nodes
Where does lymphatic drainage from the nipple and areola go?
drains to the subareolar lymphatic plexus.
What innervates the breast?
anterior and lateral cutaneous branches of the 4th to 6th intercostal nerves
Outline the embryological development of the breasts?
The mammary glands are derived from 2 thickened strips of epidermal ectoderm, the primitive mammary ridges/milk lines (week 6) The ridges extend from the axillae to the inguinal regions, but rapidly regress except in the thorax
Mammary buds that persist in the thoracic region penetrate the underlying mesenchyme and give rise to several secondary buds which develop into lactiferous ducts and their branches. These are canalized by the end of the prenatal life
The fibrous connective tissue and fat of the mammary gland develop from the surrounding mesenchym The lactiferous ducts form the small ducts and alveoli
Only the main ducts are found at birth, and the gland remains undeveloped until puberty
DURING THE LATE FETAL PERIOD, the epidermis becomes depressed to form an epithelial pit on which the ducts open
The lactiferous ducts at first open onto this epithelial pit which is formed by the original mammary line
Nipple itself forms during the perinatal period due to proliferation of the mesenchyme under the areola in the area of the mammary pit. The nipple is often depressed and poorly formed during infancy
AT PUBERTY, the female mammary glands enlarge rapidly as a result of the development of fat and connective tissue. The duct system also grows, stimulated by the estrogen and progesterone of the ovary
The glandular tissue remains completely undeveloped until pregnancy when the intralobular ducts rapidly develop, form buds, and become alveoli
The male glands undergo little postnatal development
What regulates the let-down reflex?
Prolactin helps make the milk, while oxytocin causes the breast to push out the milk
Whats the most common cancer in women who do not smoke?
Breast cancer
Whats the prevalence of breast cancer?
1 in 8 women will develop it in their lifetime
What causes physiological breast development?
At the time of menarche, oestrogen receptors in breast tissue react to ovarian oestrogen secretion which stimulates milk duct epithelial cells to divdide
What are the risk factors of breast cancer?
Female
Increased oestrogen exposure - earlier onset of periods and late menopause
More dense breast tissue
Obesity
Smoking
Fhx first degree relatives
BRCA1/2 or p53 mutations
HRT, particularly combined HRT
Combined contraceptive pill causes a small increased risk
Previous treatment using radiation therapy
Exposure to the drug diethylstilbestrol
First pregnancy after 30
Not breastfeeding
Nulliparity
What proportion of breast cancers are in females?
99%
What proportion of pt with breast cancer have a genetic predisposition?
5%
What is the main genetic predisposition for breast cancer?
BRCA mutant carriers
What do the BRCA genes put you at risk of?
Breast and ovarian cancer
BRCA2 can also put you at risk of prostate cancer
What is the BRCA gene?
Tumour suppressor genes
Where are the BRCA genes found?
BRCA 1 gene on chromosome 17
BRCA 2 gene on chromosome 13
Outline the risks of being a BRCA 1 gene carrier?
70% will develop breast cancer by 80
50% will develop ovarian cancer
Outline the risks of being a BRCA 2 gene carrier?
Around 60% will develop breast cancer by aged 80
Around 20% will develop ovarian cancer
Increased risk of prostate cancer
What screening is available for breast cancer?
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.
What is a mammogram?
X-ray images of the breast
Which groups of people are considered high risk patients for breast cancer?
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 or one first-degree and one second-degree relative diagnosed with breast cancer at any age
one first-degree or second-degree relative diagnosed with breast cancer at any age and one first-degree or second-degree relative diagnosed with ovarian cancer at any age
three first-degree or second-degree relatives diagnosed with breast cancer at any age
What are high-risk breast cancer patients offered for prevention?
Genetic counselling, pre-test counselling and genetic tests.
Annual mammogram screening potentially starting from the age of 30
Chemoprevention
Risk-reduced bilateral mastectomy or oophorectomy
What chemoprevention can be offered to women at high risk of breast cancer?
Tamoxifen if premenopausal
Anastrozole if postmenopausal (except with severe osteoporosis)
How does breast cancer present?
Typically a painless, increasing mass that may be associated with nipple discharge, skin tethering, ulceration and in inflammatory cancers, oedema and erythema
Lumps that are hard, irregular, painless or fixed in place
Lumps may be tethered to the skin or the chest wall
Nipple retraction
Skin dimpling or oedema (peau d’orange)
Lymphadenopathy, particularly in the axilla
What are the referral criteria for suspected breast cancer?
The NICE guidelines recommend a two week wait referral for suspected breast cancer for:
An unexplained breast lump in patients aged 30 or above
Unilateral nipple changes in patients aged 50 or above
The NICE guidelines recommend also considering a two week wait referral for:
An unexplained lump in the axilla in patients aged 30 or above
Skin changes suggestive of breast cancer
The NICE guidelines suggest considering non-urgent referral for unexplained breast lumps in patients< 30 years.
What are the types of breast cancer?
Non-invasive:
- ductal carcinoma in situ
- lobular carcinoma in situ
- Paget’s disease
Invasive
- invasive ductal cancer
- invasive lobular cancer
- metaplastic cancer
- medullary cancer
- inflammatory breast cancer
Other
- adenoid cystic, secretory and apocrine cancers
- Phyllodes tumours (sarcoma)
What type of breast cancer are most inflammatory breast cancers?
Invasive ductal carcinomas
Whats the most common type of breast cancer?
Invasive ductal carcinoma
What has invasive ductal carcinoma recently be renamed as?
No special type or not otherwise specified
What are the special types of breast cancer?
Lobular breast cancer
Medullary breast cancer
Mucinous (mucoid or colloid) breast cancer
Tubular breast cancer
Adenoid cystic carcinoma of the breast
Metaplastic breast cancer
Lymphoma of the breast
Basal type breast cancer
Phyllodes or cystosarcoma phyllodes
Papillary breast cancer
Whats the 5 year survival for beast cancer?
85%
What is breast carcinoma in situ?
a malignancy of the ductal tissue of the breast that is contained within the basement membran. I.e. have not spread into the surrounding breast tissue.
These carcinoma types represent a precursor to invasive breast cancer. They are rarely symptom acts
The 2 main types are DCIS and LCIS
Whats the most common type of non-invasive breast malignancy?
Ductal carcinoma in situ
What are the 5 major types of DCIS?
Based upon histolgical features:
Comedo, cribriform, micropapillary, papillary and solid types
(Most lesions are mixed)
What is lobular carcinoma in situ?
a non-invasive lesion of the secretory lobules of the breast that is contained within the basement membrane
Much rarer than DCIS but greater risk of developing invasive breast maliganncy - 30% of cases
When is lobular carcinoma in situ usually diagnosed?
Before menopause
Which type of DCIS is a high-grade type and has an increased risk of invasion?
Comedo DCIS
What proportion of invasive breast cancers are invasive ductal carcinomas?
70-80%
What proportion of invasive breast cancers are invasive lobular carcinomas?
5-10%
Which breast cancers cannot be seen on mammogram?
Lobular carcinoma in situ
Invasive lobular carcinomas (sometimes visible)
How does inflammatory breast cancer differ from other types of breast cancer?
It occurs in younger women i.e. <40
More common among women who are overweight
More aggressive
Always at a locally advanced stage (stage 3) when first diagnosed because breast cancer cells have grown into the skin
Presents similarly to a breast abscess or mastitis - Swollen, erythema over more than 1/3rd of the breast, warm, tender breast with pitting skin (peau d’orange)
Does not respond to antibiotics
Worse prognosis than other breast cancers
What is Paget’s disease of the nipple?
An erythematous scaly rash on the nipple or areola that looks like eczema
It indicates ductal carcinoma extending up through lactiferous ducts and onto the nipple area.(can be DCIS or invasive carcinoma) Present in 1-2% of pt with breast cancer
50% have an underlyign mass lesion with 90% of these having an invasive carcinoma
30% without a mass lesion will have an nderlyig carcinoma
20% will have a carcinoma in situ
What is done at the 2 week wait referral for suspected cancer?
Triple diagnostic assessment:
Clinical assessment
Imaging
Biopsy
What imaging should be done for suspicions of breast cancer?
Younger women i.e. <30 - USS
Older women - mammograms
MRI may be used
Why are USS used instead of mammograms in women <30 undergoing testing for breast cancer?
Younger women generally have more dense breasts with more glandular tissue. They are helpful in distinguishing solid lumps (e.g., fibroadenoma or cancer) from cystic (fluid-filled) lumps.
Why are mammograms better than USS for looking for signs of breast cancer?
Mammograms can capture microcalcifications whilst USS cannot
Mammograms are more effective in older woman
How are lymph nodes assessed when investigating for breast cancer?
All women are offered an ultrasound of the axilla and ultrasound-guided biopsy of any abnormal nodes.
A sentinel lymph node biopsy may be used during breast cancer surgery where the initial ultrasound does not show any abnormal nodes.
How is a sentinel lymph node biopsy done?
An isotope contrast and a blue dye are injected into the tumour area. The contrast and dye travel through the lymphatics to the first lymph node. The first node in the drainage of the tumour area shows up blue and on the isotope scanner. A biopsy can be performed on this node, and if cancer cells are found, the lymph nodes can be removed.
What are the 3 types of breast cancer receptors?
Oestrogen receptors
Progesterone receptors
Human epidermal growth factor (HER2)
What is triple-negative breast cancer and why does it carry a worse prognosis?
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.
What is gene expression profiling?
assessing which genes are present within the breast cancer on a histology sample. This helps predict the probability that the breast cancer will reoccur as a distal metastasis (away from the original cancer site) within 10 years.
Who does NICE reccomend should undergo gene expression profiling?
women with early breast cancers that are ER positive but HER2 and lymph node negative. It helps guide whether to give additional chemotherapy.
Where does breast cancer typically metastasise to?
Lungs
Liver
Bones
Brain
How is staging done for breast cancer?
Triple assessment
Additional investigations may be required to stage the breast cancer:
Lymph node assessment and biopsy, MRI of the breast and axilla, Liver ultrasound for liver metastasis, CT of the thorax/abdomen/pelvis for lung/abdominal/pelvic metastasis, Isotope bone scan for bony metastasis
What system is used to stage breast cancer?
TNM staging
What are the options for managing breast cancer?
Surgery
Radiotherapy
Hormone therapy
Biological therapy
Chemotherapy
What are the surgical options for early breast cancer?
Wide local excision and segmental mastectomy with breast conservation for masses of <3cm in diameter
Simple mastectomy with or without reconstruction is used for larger tumours
What proportion of breast tumours are removed with wide-local excision?
2/3rds
What factors determine whether mastectomy or wide local excision is done for breast cancer?
Mastectomy is for multi focal tumours, centra tumours, large lesions in small breasts and DCIS >4cm
Wide local excision is best for a solitary lesions, peripheral tumours, small lesions in large breasts and DCIS <4cm
What is the risk with axillary clearance?
The greater the amount of axillary surgery, the greater the risk of postoperative lymphoedema
Who will require adjuvant radiotherapy in breast cancer?
Those undergoing breast-conserving surgery
Those with large, high-grade primary tumours
Those undergoing mastectomy who have disease close to resection margins
Lymph node metastasis
What are the common side effects of radiotherapy for breast cancer?
General fatigue from the radiation
Local skin and tissue irritation and swelling
Fibrosis of breast tissue
Shrinking of breast tissue
Long term skin colour changes (usually darker)
What is lymphoedema?
a chronic condition caused by impaired lymphatic drainage of an area. Lymphoedema can occur in an entire arm after breast cancer surgery on that side, with removal of the axillary lymph nodes in the armpit.
Areas of lymphoedema are prone to infection
Whats the non-surgical management for lymphoedema?
Massage techniques to manually drain the lymphatic system (manual lymphatic drainage)
Compression bandages
Specific lymphoedema exercises to improve lymph drainage
Weight loss if overweight
Good skin care
In what proportion of all breast cancers is Human Epidermal growth factor Receptor 2 overexpressed?
In 20% of all breast cancers
What do HER2-positive cancers respond to?
treatment with HER2 inhibitors such as trastuzumab and pertuzumab
What can be used to manage oestrogen receptor-positive disease?
Endocrine therapy. There are 2 strategies:
- oestrogen receptor blockade using tamoxifen or fulvestrant
- oestrogen deprivation using aromatase inhibitors such as anastrazole (post-menopausal)
Why are post-menopausal woman given aromatase inhibit so rather than tamoxifen for oestrogen receptor-positive breast cancer?
as aromatisation accounts for the majority of oestrogen production in post-menopausal women and therefore anastrozole is used for ER +ve breast cancer in this group.
What are the important side efefcts of tamoxifen?
increased risk of endometrial cancer, venous thromboembolism and menopausal symptoms.
Who cannot have trastuzumab?
patients with a history of heart disorders.
How may chemotherapy be used in the management of breast cancers?
Neoadjuvant therapy – intended to shrink the tumour before surgery
Adjuvant chemotherapy – given after surgery to reduce recurrence
Treatment of metastatic or recurrent breast cancer
Whats the moa of tamoxifen?
is a selective oestrogen receptor modulator (SERM).
It either blocks or stimulates oestrogen receptors, depending on the site of action.
It blocks oestrogen receptors in breast tissue, and stimulates oestrogen receptors in the uterus and bones. This means it helps prevent osteoporosis, but it does increase the risk of endometrial cancer.
Whats the moa of Trastuzumab (Herceptin)?
A monoclonal antibody that binds to an extracellular domain of this receptor and inhibits HER2 homodimerization, thereby preventing HER2-mediated signaling. It is also thought to facilitate antibody-dependent cellular cytotoxicity, leading to the death of cells that express HER2.
Whats the moa of pertuzumab?
A monoclonal antibody that binds to the extracellular domain II of HER2
What follow up should be done after treatment for breast cancer?
Surveillance mammograms yearly for 5 years (longer if not yet old enough for regular breast screening programme)
What are the 2 options for reconstructive surgery?
Immediate reconstruction, done at the time of the mastectomy
Delayed reconstruction, which can be delayed for months or years after the initial mastectomy
After breast-conserving surgery, reconstruction may not be required but what can be given if needed?
Partial reconstruction (using a flap or fat tissue to fill the gap)
Reduction and reshaping (removing tissue and reshaping both breasts to match)
After mastectomy what are the options for breast reconstruction?
Breast implants (inserting a synthetic implant)
Flap reconstruction (using tissue from another part of the body to reconstruct the breast)
What are the pros and cons of breast implants?
It gives an acceptable appearance but can feel less natural (e.g., cold, less mobile and static size and shape). There can also be long-term problems, such as hardening, leakage and shape change.
May need to be replaced after about 10 years
Body can have an inflammatory reaction to the implants
What can be used as flap reconstruction for breast cancer surgery?
Latissimus Dorsi
Rectus abdominis
Free flap - skin and subcutaneous fat from abdomen
What does pedicled mean?
refers to keeping the original blood supply and moving the tissue under the skin to a new location.
What is a free flap?
cutting the tissue away completely and transplanting it to a new location.
Whats a TRAM flap?
Transverse rectus abdominis flap
Whats the risk of a TRAM flap?
It poses a risk of developing an abdominal hernia due to the weakened abdominal wall.
Whats a DIEP flap?
Deep Inferior Epigastric Perforator Flap
Outline how a DIEP flap is done? (You have seen this in surgery in Hull!)
The deep inferior epigastric artery, with the associated fat, skin and veins, is transplanted from the abdomen to the breast. The vessels are attached to branches of the internal mammary artery and vein.
Abdominal walls are left intact so less risk of hernia!
What are the pros and cons of immediate vs delayed breast reconstruction?
Immediate - better cosmetic outcomes, cheaper, psychoglocial benefit
Delayed - more time to consider options, adjuvant therapy, higher pt satisfaction rates
What is lipomodelling?
Autologous fat transfer
Fat removed from areas of excess by liposuction -> fat centrifuged in theatre to remove blood and dead cells -> fat re-injected into breast to augment reconstruction
What is a lumpectomy?
surgery to remove a breast cancer tumor and the margin
What findings can be seen on a mammogram in DCIS?
Microcalcifications
What is the Nottingham Prognostic index?
a prognostics measure that predicts operable primary breast cancer survival
How is the Nottingham Prognostic Index calculated?
Tumour size x 0.2 + lymph node score + grade score
Score 1 = 0 lymph nodes involved and grade 1
Score 2 = 1-3 lymph nodes involves and grade 2
Score 3 = >3 lymph nodes involved and grade 3
How do you interpret Nottingham prognostic index?
2-2.4 = 93% 5 year survival
2.5-3.4 = 85% 5 year survival
3.5-5.4 = 70% 5 year survival
>5.4 = 50% 5 year survival
Outline TNM staging for breast cancer?
Tx
Tis (DCIS) - ductal carcinoma in situ (pre-invasive breast cancer)
Tis (Paget) - Paget’s disease
T1 - tumour =/<2cm (divided into T1mi, T1a, T1b and T1c)
T2 - tumour 2cm-5cm
T3 - tumour >5cm
T4 - T4a means the tumour has spread into the chest wall, T4b means tumours spread into skin, T4c tumour spread to skin and chest wall, T4d means inflammatory carcinoma
N - clinical node staging and pathological node staging
M0 - no metastasis
CMo(i+) - no sign of the cancer on physical examination, scans or x-rays but cancer cells are found by lab tests
cM1 - cancer spread
PM1 - cancer measuring more than 0.2 mm across has spread to another part of the body
What proportion of DCIS will progress into invasive disease?
About 20%
How many lactiferous ducts are present in each breast?
15-20