Breast cancer

Question 1

Anatomy

Answer 1

Functional and histological unit of the breast = terminal duct lobular unit (TDLU). Made up of glandular tissue producing milk. Drainage system:
- Lobule
- Terminal duct
- Collecting duct
- Taking milk to the nipple

Question 2

Where do moat cancers and benign lesions occur

Answer 2

TDLU

Question 3

Lobules and ducts layers

Answer 3

Lined by an epithelium consisting of two layers:
- Inner luminal epithelial cells
- Outer myoepthithelial cells

Question 4

Where do most cancers occur

Answer 4

upper outer quadrant

Question 5

Lymph node drainage

Answer 5

75% = axillary lymph nodes
20% = parasternal nodes
5% = posterior and intercostal nodes

Question 6

Where do mets go first

Answer 6

The sentinel lymph node is the axillary lymph node due to its proximity to the breast = has implications with regards to staging and management

Question 7

Epidemiology

Answer 7

General risk factors
- Increasing age
- Female: 99% of cases occur in females
- Previous history of breast cancer
- Family history
- Proliferative lesions: atypical hyperplasia
- Alcohol
- Smoking

Question 8

Genetic risk factors

Answer 8

BRCA1/BRCA2:
- tumour suppressor gene involved in DNA repair
Increased risk of breast and ovarian cancer
- MC cause of hereditary breast cancer
- Male breast cancer associated with BRCA2
- Li-Fraumeni syndrome: autosomal dominant p53 mutation
- Breast, brain, adrenal, leukaemia/lymphoma, osteosarcoma

Peutz-Jeghers syndrome
- Benign intestinal hamartomas and malignancies involving GI tract, breast, pancreas, and GU tract

Klinefelter syndrome: 47 XXY
- Increased risk of breast cancer in men

Question 9

Hormonal risk factors

Answer 9

Increased oestrogen exposure
- Endogenous
= Obesity
= Early menarche
= Late menopause
= Late pregnancy/ nulliparity
= Breastfeeding and multiparity are protective
- Exogenous oestrogen
= HRT
= Oral contraceptive use

Question 10

Signs

Answer 10

Palpable mass
- Firm and non-tender
- Poorly defined
- Located in the upper outer quadrant most commonly
Evidence of metastasis:
- Axillary lymphadenopathy
- Bone
- Liver
- Lung
- Brain

Question 11

Symptoms

Answer 11

Painless lump
- Breast
- Axilla
Skin changes
- Tethering: mass fixes to surrounding structures, e.g. fascia, pectoral muscle, or Cooper ligaments
- Discolouration
- Erythema, swelling and Peau d’orange are suggestive of inflammatory carcinoma
Nipple changes:
- Inversion
- Bloody discharge
- Eczema

Question 12

2 week wait criteria

Answer 12

• 30+ and have an unexplained breast lump with or without pain
• 50+ and over with any of the following symptoms in one nipple only:
  = Discharge
  = Retraction
  = Other changes of concern

Question 13

Considerations for 2 week wait

Answer 13

• Skin changes that suggest breast cancer
• 30+ with an unexplained lump in the axilla

Question 14

A non-urgent referral

Answer 14

<30 with an unexplained breast lump with or without pain

Question 15

Diagnosis

Answer 15

• History and examination:
• Imaging
  = Mammography: varied appearance but include an irregular spiculated mass, and calcification
  = Ultrasound: adjunct to mammography esp in younger patients (< 40 years old) with denser breasts.
• Features include a hypoechoic irregular mass, architectural distortion, and calcification

Question 16

Types of biopsy

Answer 16

Core biopsy
Fine needle aspiration

Question 17

Management

Answer 17

Surgical therapy:
- Breast-conserving: wide-local excision is indicated in localised smaller tumours
Mastectomy:
- Total mastectomy
- Skin-sparing
- Nipple-sparing
- Radical mastectomy
- Modified radical mastectomy
Axillary surgery:
- Sentinal lymph node biopsy: Px with no detectable axillary lymphadenopathy preoperativly = sentinel node identified (first node the breast cancer will metastasise to).
- Axillary lymph node dissection: Px with known axillary lymphadenopathy = multiple axillary lymph nodes are removed

Question 18

Indications for breast conserving therapy

Answer 18

• Localised
• Small tumour size:breast ratio

Question 19

Indications for mastectomy

Answer 19

• Multifocal
• Large tumour size:breast ratio
• Breast-conserving surgery tissue removed has positive margins
• Significant skin involvement
• DCIS > 40mm

Question 20

Adjuvent management to breast conserving surgery

Answer 20

Radiotherapy
- Indicated in those who have had breast
- Considered in those who have had mastectomy if there are multiple lymph nodes positive, large tumours and/or positive margins.

Question 21

Hormone therapy

Answer 21

Indicated if the patient is ER-positive and continued for 5-10 years
- Premenopausal: majority of oestrogen produced by ovaries
- Selective oestrogen receptor modulators: e.g. tamoxifen and toremifene
- Ovarian suppression: GnRH analogues like goserelin can also be used

Question 22

Biological therapy

Answer 22

Indicated if HER2 positive
- Trastuzumab: also known as Herceptin, blocks HER2

Question 23

Chemotherapy

Answer 23

• Can be adjuvant or neoadjuvant
• Chemotherapy should be considered in the following:
  = Triple-negative disease
  = Early-stage disease and high risk of recurrence e.g. triple-negative or HER2 positive
  =Lymph node positive disease
  = Advanced disease

Question 24

Complications

Answer 24

Cancer-related
- Metastasis: bone, liver, lung, brain
- Malignant pleural effusion
- Recurrance
Treatment-related
- Surgery:
= cosmetic defect e.g. asymmetry
= seroma
= lymphoedema post-axillary node dissection
- Hormone and biologic therapy
= Tamoxifen: increased risk of endometrial cancer and VTE
= Herceptin: cardiotoxic
= Aromatase inhibitor: osteoporosis
- Chemotherapy
= Neutropaenia
= Taxanes: peripheral neuropathy