 Most commonly diagnosed cancer among women in Australia.  Lifetime risk of 1 in 9, risk increases with age.

 Each breast contains lobes arranged in a circular fashion.  Each lobe is made up of lobules with milk- producing glands at the end.  Cancers develop through molecular changes in breast epithelial cells, especially of hormonal receptors.

Carcinoma in situ  DCIS › Presentation – mass, pain, nipple discharge. › MMG – microcalcifications. › High risk of progression to invasive breast cancer.  LCIS › Usually incidental finding without clinical symptoms. › Originates from terminal breast lobules. › Marker of increased risk of invasive breast cancer in either breast. Invasive breast cancer  IDC (70-80%)  ILC (5-10%)

 Age  FHx › ≥1 st degree relative › Young age at diagnosis › Ovarian cancer › Male breast cancer › Ashkenazi Jews  Breast disease › Neoplastic – DCIS, LCIS › Benign  Genetic › BRCA 1/2 mutations › Other – p53 etc.  Hormonal › Endogenous – menstrual, obstetric history › Exogenous – OCP, HRT

 Presentation › Asymptomatic – screening › Symptomatic – breast lump, nipple changes  Examination › Breast – lump, skin changes › Nipple – inversion, discharge › Axilla – lymphadenopathy › Metastatic – respiratory, abdominal, bone pain, neurological

 Mammogram › Asymmetry › Micro- calcifications › Mass › Architectural distortion  Ultrasound  MRI › Screening of high risk patients

 Core biopsy – breast lesion › Histology – IDC, ILC, DCIS, LCIS › Grade › Receptors - ER, PR, Her2 › Lymphovascular invasion › Necrosis  FNA – LNs  Triple test = positive if any component is indeterminate, suspicious or malignant  requires specialist referral  99.6% sensitivity

 Staging – TNM › T – histopathology › N – SLN biopsy › M – CT, bone scan (not always indicated for early cancers due to low risk of metastases)  Baseline assessment › Myocardial function – MUGA/echo prior to chemotherapy/Herceptin

Breast  Wide local excision ± SLNB/axillary dissection + radiotherapy › Clear histological margins with rim of normal breast tissue › Indications – unifocal, <3-4cm › Localisation – carbon/hook-needle › Approach – circumareolar incision for subareolar/central breast lesions, parallel to Langer’s lines  Mastectomy › Complete excision of breast parenchyma › Indications – multifocal, large tumour size, prior RTx, personal preference › Drains inserted to prevent seroma/haematoma formation  WLE vs. mastectomy › No difference in metastases or survival between mastectomy vs. WLE + RTx › Higher incidence of local recurrence in WLE (1-2%/year) vs. mastectomy (0.5%/year).  Breast reconstruction › Immediate vs. delayed › Implant vs. flaps

Axilla  Prognosis – axillary LN status is best prognosticator of disease- free interval and survival. 30% of patients with early cancer have positive axillary LNs.  Axillary dissection › Removal of level 1/2 axillary LNs › Previously gold standard but high morbidity.  SLN biopsy › Minimally invasive procedure designed to stage axilla in patients with clinically negative nodes. › Suitable for clinically node negative unifocal tumours <3cm. › Equivalent accuracy to axillary dissection. › Technique – inject radioactive tracer and blue dye  1-3 LNs tested for metastases  intraoperative frozen section  immediate axillary dissection if positive.  Adjuvant therapy – with axillary LN involvement RTx improves disease-free survival and reduces local recurrence.

 DCIS  Resection of primary cancer  Adjuvant radiotherapy

 Post-operative complications › Seroma › Wound infection › Bleeding › Need for re-excision

 Eradicate local subclinical disease  Indications › After WLE of DCIS/early breast cancer › After mastectomy if positive margins, large primary tumour, ≥4 LNs+  Side effects › Early – fatigue, pain, skin changes › Late – oedema, pain, fibrosis, hyperpigmentation

 Chemotherapy agents › Alkylating agents, e.g. cyclophosphamide › Anthracyclines, e.g. doxorubicin › Antimetabolites, e.g. 5FU, gemcitabine, methotrexate › Taxanes, e.g. paclitaxel › Vinorelbine  Adjuvant › Indications  Locally advanced/metastatic cancer.  LN- and <0.5cm – not recommended.  LN- and 0.6-1cm – recommended if high risk factors. › Regimen  Combination recommended  Assess tumour responsiveness every 6-12 weeks (2-3 cycles)  If disease control is confirmed, should be continued for weeks (6-8 cycles)  Neoadjuvant › Indications  Large/locally advanced breast cancer prior to surgery and radiotherapy.

ER +  Decrease oestrogen's ability to stimulate existing micrometastases or dormant cancer cells.  Treatment for 5 years  Tamoxifen › Pre- and post-menopausal patients › Side effects – hot flushes, nausea, vomiting, fluid retention  Aromastase inhibitors › Post-menopausal patients › Side effects - osteoporosis Her2+  20% of breast cancers are Her2+; more aggressive.  Trastuzumab (Herceptin)  Side effects – cardiac toxicity

 Clinical review every 6 months for first 2 years then annually thereafter.  Mammogram at 6 months then annually thereafter.  Further investigations as dictated by symptoms.  DEXA scan for patients on aromatase inhibitors.

 Wright, M. (2011). Surgical treatment of breast cancer. Accessed Sep 1,  Swart, R. (2012). Adjuvant therapy for breast cancer. Accessed Sep 1,  Stopeck, A. (2012). Breast cancer. Accessed Aug 26,  NBOCC Recommendations for staging and managing the axilla in early (operable) breast cancer (2011). Accessed Aug 26,  NBOCC Recommendations for Aromatase inhibitors as adjuvant endocrine therapy (2006). Accessed Aug 26,  NBOCC Recommendations for use of sentinel node biopsy (2007). Accessed Aug 26,  Uptodate