Breast Cancer Flashcards
Give 8 predisposing factors for breast cancer
Female Increasing age Early menarche Late menopause Nulliparity Late 1st pregnancy Caucasian DCIS/LCIS Obesity Family Hx of breast cancer BRCA1 gene Long term COCP use HRT Previous radiotherapy Previous cancer- melanoma, lung, bowel, uterine, CLL Excess alcohol Lack of exercise
Give 4 protective factors for breast cancer
Physically active Breastfeeding Healthy diet Medication- regular aspirin, Anastrozole Prophylactic bilateral mastectomy (+/- reconstruction)
Explain the pathophysiology of Ductal Carcinoma in Situ (DCIS)
Atypical proliferation of the ductal epithelium that eventually fills and plugs the duct with neoplastic cells. Remains within the confines of the ductal basement membrane. Often found incidentally on mammogram.
30-50% chance of becoming invasive
Explain the pathophysiology of Lobular Carcinoma in Situ (LCIS)
Atypical proliferation of the breast lobule cells (cells which make milk). The abnormal cells are all contained within the inner lining of the lobules. Not visible on mammogram- found incidentally on biopsy
Can become invasive in ipsilateral and contralateral breast
Explain the pathophysiology of invasive ductal carcinoma
75% of breast cancers
Tumour starts in the ductal cells of the breast and then invades through breast tissue and into the lymphatics and then circulation. The malignant cells have a dense fibrous stroma.
What 3 histological factors are used to grade an invasive ductal carcinoma?
Tubule formation
Nuclear pleomorphism
Mitotic frequency
Give 4 common metastatic sites for invasive ductal carcinoma of the breast
Bone Lung Pleura Liver Skin CNS
What are the 3 main types of invasive ductal carcinoma?
Oestrogen receptor positive- 60-70% of cancers express nuclear ER. Sex hormones control the tumour growth
HER-2 positive- 25-30% of cancers have excess growth factor receptor gene, HER-2. There is a high risk of lymphatic involvement and haematogenous spread.
Triple negative- do not express ER, HER-2 or PR. 15% of breast cancers. More common in patients with BRCA1 gene and postmenopausal. Express EGFR.
Where do invasive lobular carcinomas often spread to?
Unusual pattern of spread
Peritoneum
Meninges
Ovary
Uterus
What is Paget’s Disease of the breast?
Cancer cells collect in or around the nipple, starting in the ducts of the nipple.
Give 4 symptoms of Paget’s Disease of the breast
Nipple skin= red, flaky, sore, scaly
Neeple bleeding/discharge
Nipple invertion
Lump under the nipple
Describe the anatomical structure of the breast
Made up of mammary glands which are modified sweat glands. They form a series of lobules and ducts. Each lobule is made up of many alveoli drained by a single lactiferous duct.
The lobules are supported by connective tissue stroma made up of fatty and fibrous tissue. The fibrous stroma forms suspensory ligaments which separate the secretory lobules and attach the breast to the underlying fascia.
The pectoral fascia is a flat sheet of connective tissue associated with the pectoralis major.
Which nerves supply the breast?
Anterior and lateral cutaneous nerve branches of the 4th and 6th intercostal nerves.
Which hormone controls milk secretion?
Prolactin
Which 3 groups of lymph nodes does the breast tissue drain into?
Axillary nodes (75%) Parasternal nodes (20%) Posterior intercostal nodes (5%)
