Breast Oncology Flashcards
Aetiology & Risk Factors?
increasing age
Family history
Endogenous hormone factors
Reproductive – lower age at menarche, older age at menopause, nulliparous, older at time of first birth. (Breast feeding protective)
Obesity in post-menopausal women
Exogenous hormone factors
Hormone replacement therapy (combined oestrogen/progesterone)
Higher socio-economic status
Moderate alcohol intake
Genetic (BRCA 1 & 2, p53, ATM)
Proliferative fibrocystic changes in breast, especially with atypia
Personal history of DCIS or invasive breast ca or endometrial ca
Previous exposure to ionising radiation – eg Hodgkin’s
Lymphatic drainage of the breast?
Laterally –> axillary lymph nodes – levels I-III
From here –>supraclavicular nodes
Medially –> internal mammary nodes (deep to 1st 3 intercostal spaces within 4cm of midline)
Pathology of breast cancer? (epithelial)
Carcinoma in situ
Ductal carcinoma in situ – proliferation of malignant cells in the ducts that does not breach the basement membrane.
Pathology of breast cancer? (Lobular)
Lobular carcinoma in situ – proliferation of malignant cells in the lobules that does not breach the basement membrane
Often more poorly defined
Greater risk of multifocality and bilaterality cf IDC
Others – including medullary, colloid (mucinous), tubular, Paget’s disease, adenoid cystic
Pathology of breast cancer? (Ductal)
Ductal (intraductal) carcinoma (infiltrating carcinoma of no special type)
Proliferation of malignant cells that breach the basement membrane
Grade 1 – 3 depending on malignant cells look and how arranged
Routes of spread?
Invasion of lymphatics risk of spread to lymph nodes (axilla, supraclavicular fossa, internal mammary nodes) & subsequent vascular spread & distant mets
Symptoms & signs of breast cancer?
• Lump – most commonly related to benign disease
• Change in size or shape
• Nipple discharge, itching, bleeding or retractions
• Skin changes
–>Fungation or ulceration from direct invasion
–>Dimpling from underlying tumour fixation
–>Lymphoedema due to invasion of dermal lymphatics (peau d’ orange)
–>Erythema and warm from inflammatory breast cancer
How does the Her 2 gene cause breast cancer?
- Cell which leads to cell proliferation
- Gene amplification → overexpression → uncontrolled activation → proliferation and metastasis
- Overexpression in 25% of breast cancers
Clinical presentation of breast cancer includes?
• Pain (uncommon)
• Nodal disease – palpable nodes, arm oedema, nerve
• Distant metastases
• Usually asymptomatic mammographic abnormality
o Soft tissue mass
o Miro calcifications
What is the aim of early screening methods?
o Aim – get tumour while still small and confined in breast
o Breast self-examination, clinical breast examination, screening mammography
What does mammography screening involve?
o Every 2 years for women 50-69 age group reduces mortality 20-35%
o False -ve and +ves can occur → higher in young women due to dense breasts
o No need in older women as co-morbid conditions compete for high risk of mortality
• After screening biopsy → definitive surgery → high risk metastatic disease CT head, chest, abdo and pelvis scans and bone scans
TNM stage 1 for breast cancer?
Stage O non invasive (DCIS or LCIS)
TNM stage2 for breast cancer?
Stage 2 = primary >2 but <5cm, 1-3 nodes or >5cm no nodes
TNM stage 3 for breast cancer?
Stage 3 = primary >5cm with nodes or involves skin or chest wall or >4 axillary nodes
TNM stage 4 for breast cancer?
Stage 4 = tumour spread distantly usually to lung, liver and bone
Early breast cancer management?
Surgery, radiotherapy, chemotherapy, endocrine therapy → better outcome using full range of treatment options
Possible treatment sequences after surgery?
Chemo → RT
RT → chemo
Chemo → RT → Chemo
Concurrent
What does sentinel node biopsy involve?
Ist draining node within a LN basin to receive lymphatic drainage from a tumour site
<10% false -ve rate
What is the aim of breast cancer surgery?
Aim is to excise all tumour
What is a modified radical mastectomy?
Removal of whole breast and underlying fascia over pectoralis major muscle with axillary dissection
What does breast conversing surgery involve?
Wide local excision +/- axillary dissection and RT to whole breast
Why might breast conserving surgery not be suitable for all patients?
Multicentric disease, diffuse microcalcifications, inflammatory, previous RT, pregnancy, persistently +ve margins after re-excision
Why might we use adjuvant radiotherapy?
o Either as part of breast conserving therapy or following mastectomy
o Reduces risk of local recurrence by 70% and all recurrence by 50%
o Even small no nodal cancers show benefit from radiation therapy
o Tamoxifen alone following lumpectomy is a realistic choice only for women >70 with small completely resected ER +ve tumour
o RT to supraclavicular, axilla and internal mammary nodes if regional nodal involvement and risk of relapse
What are the field inclusion margins for the breast? (supine)
WHOLE BREAST: Medial, 1cm lat, 1cm inf, sup to include all breast tissue (lower edge of clavicular head to base of axilla)
CHEST WALL: entire mastectomy scar with bolus (may by alternate days on and off or full and scar)
NODAL: if high suspicion of occult nodal disease
SUPRA CLAV: >4 axillary nodes involved (inf to 2nd costal cartilage, medial, lat at coracoid process, sup at cricoid cartilage)
AXILLARY: increase risk of lymphoedema and not usually done if dissection has been performed, treated if residual disease
INTERNAL MAMMARY: involvement increase with medial tumours however very hard area to irradiate and can use either extended tangents, matched electron field, IMRT/VMAT
Early side effects of breast cancer?
- GI (nausea, vomiting, diarrhoea)
- Hair loss
- Myelosuppression
- Fatigue
Late side effects of breast cancer?
- Heart failure
- Premature menopause and infertility
- Cognitive dysfunction
What is inflammatory breast cancer defined by?
• Defined by
o Oedema >1/3 breast
o Erythema >1/3 breast
o Palpable border to erythema
• Usually Her2, node negative and younger
• Treatment same as LABC with Herceptin if Her2 +ve or HT if ER/PR +ve
Where is the inflammatory breast cancer most breast likely to spread to?
Lung, bong and liver
What is the chance of survival after having inflammatory breast cancer for 5 years?
5-10%
Treatment of inflammatory breast cancer?
• Surgery, RT, HT, chemo, Her2, bisphosphonates (inhibit osteoclasts which slows down bone resorption around metastases in bone)
How does the use of chemotherapy benefit cancer patients?
Significantly reduces risk of death from breast cancer for all patients with greater benefit in young women or with nodal involvement
What is the traditional chemotherapy regime?
CMF (cyclophosphamide, methotrexate, 5FU)
Late side effects of breast cancer?
- Breast/arm oedema or Shrinkage
- Pain and tenderness
- Rib fracture
- Skin telangiectasia
- Symptomatic lung fibrosis and Cardiac morbidity
OAR for the breast?
- Heart
- Lung
- Contralateral breast
Acute affects of breast irradiation treatment?
- Skin changes (Erythema, dry/moist desquamation)
- Oedema
- Fatigue
- Pharyngitis (SCF)
Late side effects of breast irradiation treatment?
- Cosmesis (Fibrosis, pigmentation change, telangiectasia)
- Lung (Pneumonitis)
- Cardiac (Ischaemic heart disease)
- Rib osteitis
- Lymphoedema
- Brachial plexopathy
- Second malignancy (lung, sarcomas)
What is the standard dose for breast treatment?
50Gy in 25#
What is the standard dose for hypo-fractionated treatment?
42.5Gy in 16#
How does hypo-fractionated dose improve treatment?
- a/b ratio is low and thus bigger fraction sized may be more effective
- trials showed similar local control and cosmesis
Electron boost to tumour bed fractionation? Why is this beneficial?
16Gy in 8#, 10Gy in 5#•
Shows small but significant reduction in local recurrence especially in women <50
Why do we use IMRT for breast?
- Reduces heterogeneity
- Conformal target volumes
- Reduced heart and lung dose
- Regional node improvement
- Odd shaped chest
What do we need to consider for IMRT plans?
can be used to improve plans but need to consider respiratory motion and increased dose to contralateral breast
Partial breast irradiation techniques?
- 3D conformal or IMRT
- Brachytherapy (interstitial or intracavitary)
- Intra-operative RT
What is a negative of partial breast irradiation?
o Show a higher local recurrence with no trials to confirm equivalent to standard treatment
What are two examples of hormone therapy?
Tamoxifen
Aromatase Inhibitor
