Malignant Breast Pathology Flashcards
What is the lifetime risk of breast carcinoma?
1 in 8
State at least 5 risk factors for breast carcinoma
Female gender, BRCA1 or BRCA2 mutations (up to 85% lifetime risk), hormone exposure (early menarche, late menopause, nulliparity, OCP, HRT), advancing age, FHx, Caucasian race, obesity, smoking, alcohol, radiation exposure
Define Paget’s disease of the nipple
Eczema of the nipple then areola, often associated with breast cancer
Between what ages are women offered 3-yearly mammography?
47-73
Define carcinoma in situ
Neoplastic epithelial proliferation limited to the ducts or lobules by basement membrane
How is lobular carcinoma in situ diagnosed?
Always an incidental finding on biopsy as cells lack microcalcifications or stromal reactions
What % of lobular carcinoma in situ is bilateral?
20-40%
Describe the histology of ductal carcinoma in situ
Ducts filled with atypical epithelial cells
How is ductal carcinoma in situ diagnosed?
Areas of microcalcification on mammography, confirmed by biopsy
Define invasive breast carcinoma
Malignant epithelial tumours which infiltrate within the breast and can metastasise to distant sites
State the four types of invasive breast carcinoma
Ductal, lobular, tubular, mucinous
Describe invasive ductal carcinoma
The most common invasive breast cancer, made of cells that cannot be classified into another group - large, pleiomorphic cells that move into the stroma
Describe the histology of invasive lobular carcinoma
Cells aligned in single file chains or strands
Describe invasive tubular carcinoma
Rarely palpable as <1cm in size. Well-formed tubules with low grade nuclei
What is the main feature of invasive mucinous carcinoma?
Cells produce abundant extracellular mucin which dissects into surrounding stroma
Name 3 receptors all invasive breast carcinomas are assessed for, and their prognostic indication
Oestrogen receptor (good), progesterone receptor (good), HER2 receptor (bad)
What is tamoxifen?
Mixed agonist and antagonist of oestrogen at its receptor
What is Herceptin (trastuzumab)?
Monoclonal immunoglobulin antibody to Her2
What is the main side effect of Herceptin (trastuzumab)?
Direct toxic effect on myocardium
Describe the histology of basal-like carcinoma
Sheets of markedly atypical cells with lymphocytic infiltrate that stain for CK5, CK6, and CK14
Which BRCA gene mutation confers the greatest risk of male breast cancer?
BRCA2
Why is the prognosis worse in male breast cancer?
Diagnosis usually made later (stage III or IV), lack of awareness may postpone seeking medical attention, lesions are less contained as they do not have to travel as far to infiltrate skin/ nipple/ muscle tissue
