Breast Cancer

Question 1

Definition of breast cancer

Answer 1

Malignancy of the breast tissue either originating in the DUCTS or in the LOBULES

Question 2

Risk factors for breast cancer

Answer 2

• Risk factors:
• Increased oestrogen exposure:
◦ Can be due to early menarche, late menopause, nulliparity (no children means has periods for longer), OCP and HRT
• Advanced age:
◦ increased incidence with age, usually post-menopausal
• Genetic predisposition:
◦ BRCA1/BRCA2 mutations (most common mutation found in breast cancer), p53 tumour suppressor mutation
• Family history:
◦ includes breast, ovarian, endometrial and colorectal cancers
• Fibrocystic changes with atypia
• Lifestyle factors:
◦ smoking, alcohol, obesity, low fibre and high fat diet
• Past breast cancer

Question 3

Pathophysiology for breast cancer

Answer 3

• Oestrogen stimulates proliferation of breast epithelial cells in the lobules and ducts

• Majority of cancers are oestrogen receptor positive
• Some overexpress the HER2 receptor (growth factor receptor gene)

• Split into many types:
‣ Breast cancer in situ (non-invasive):
◦ Confined to the duct or lobule and have NOT penetrated the basement membrane
◦ Split again into 2 types: Ductal carcinoma in situ (DCIS) and Lobular carcinoma in situ (LCIS)
◦ DCIS is a potential precursor of invasive carcinoma (premalignant). Typically unilateral
◦ LCIS is rarer. Typically bilateral

				‣ Primary invasive breast cancer: 
						◦ Invasive ductal carcinoma is the most COMMON. 
						◦ The malignancy has penetrated past the basement membrane and spread to surround tissues, BUT has not spread to other organs

				‣ Metastatic breast cancer: Spread to other organs

Question 4

History and examination of breast cancer

Answer 4

• Breast mass:
• Usually painless. Firm, irregular and FIXED to surrounding structures
• Mass may be absent but mammographic abnormalities are present (microcalcifications)
• Change in breast shape
• Nipple discharge: Can be watery, serous, milky or BLOODY. The older you are, the more likely the discharge is linked to cancer
• Axillary lymphadenopathy: Lump in armpit. Prognostic factor for invasive carcinoma
• Weight loss, bone pain etc
• Nipple inversion
• Skin thickening and discolouration: Peau d’orange is usually always associated with locally advanced or inflammatory breast cancer
• Skin ulceration
• Fixed to chest wall
• Pagers disease of the nipple:
◦ Usually caused by ductal carcinoma in situ that can infiltrate the nipple
◦ Looks like eczema-like hardening of the skin on the nipple, erythematous, scaly etc

Question 5

Investigations for breast cancer

Answer 5

1) TRIPLE ASSESSMENT
• Clinical Examination: Firm, irregular and fixed to surrounding structures

• Imaging:
‣ Ultrasound: If young (<35). Is able to detect cysts
‣ Mammogram: If older (>35) (usually used for 50-70 year old’s breast cancer screening). Has 2 views
‣ Would see CALCIFICATIONS in the breast

• Biopsy:
‣ Fine needle biopsy: takes small amount of fluid and tissue (good for cystic lesions). Fast and easy way to biopsy
‣ Core needle biopsy: larger sample, good for solid breast cancer

2) TNM staging of the breast cancer. Do CXR, bone scan, liver USS etc

Question 6

Treatment for breast cancer

Answer 6

Low risk carcinoma IN-SITU:
1) Surgical excision or mastectomy with breast reconstruction:
◦ Generally, wide local surgical excision of the tumour (Lumpectomy) is preferred followed by adjuvant radiotherapy in order to conserve the breast
◦ May alternatively do a total mastectomy (lower risk of recurrence)
CONSIDER
Radiotherapy: to treat microscopic disease following excision

High risk carcinoma IN-SITU:
1) Mastectomy: disease recurrence is low following a total mastectomy
CONSIDER
Radiotherapy
Endocrine therapy: Tamoxifen can be used in oestrogen positive cancers to reduce oestrogen activity

Early stage breast cancer:
1) Lumpectomy or total mastectomy: Wide local incision. Radiotherapy if surgery is contraindicated
+ Sentinel lymph node biopsy or axillary lymph node dissection: Involves examining and removing sentinal lymph nodes for tumours

+ Adjuvant radiotherapy: can reduce the risk of recurrence

Locally advanced breast cancer:
1) Neoadjuvant chemotherapy: needed to downsize tumour before surgery
+ Lumpectomy or total mastectomy
+ Sentinel lymph node biopsy or axillary lymph node dissection

Question 7

Prevention and prognosis of breast cancer

Answer 7

Promote awareness, especially for those with risk factors.
Breast screening every 3 years for women aged 47-73

Prognosis dependent on age, comorbidities, TNM staging etc
Risk of recurrence

Question 8

Complications of breast cancer

Answer 8

• Chemotherapy related side effects: nausea and/or vomiting
• Metastases