BREAST PATHOLOGY Flashcards
What percentage of breast lesions received in the lab are malignant?
25% of breast lesions are malignant.
What is the most common histologic type of breast cancer?
Invasive ductal carcinoma (not otherwise specified).
What percentage of invasive ductal carcinoma cases have intraductal carcinoma present?
80% of cases have intraductal carcinoma present.
What are the key prognostic factors for breast cancer survival?
Node status, tumor size, tumor differentiation, ER/PR status, and tumor angiogenesis.
What does the presence of estrogen receptors (ER) in tumors indicate?
It identifies hormone-sensitive tumors and is associated with better survival outcomes.
What is the risk of developing breast cancer by age 70 for individuals with BRCA1 mutation?
Up to 85%.
What are the survival rates for medullary carcinoma?
80-90% 10-year survival.
Which histologic type of breast cancer has the lowest rate of axillary node metastasis?
Mucinous carcinoma (3-15% in pure form).
What is the significance of Cathepsin-D in breast cancer?
It is associated with high risk of recurrence and poor survival due to its link with node status.
What is the role of ER and PR in breast cancer prognosis?
Important for guiding hormone treatment rather than determining prognosis.
What percentage of breast cancers are ductal carcinomas?
97% of malignant breast cancers are ductal carcinomas.
What are the main risk factors for breast cancer?
Increasing age, personal/family history, BRCA1 mutation, obesity, and radiation exposure.
What is Bloom-Richardson grading used for?
To assess histologic grade based on tubule formation, mitoses, and nuclear pleomorphism.
What histologic types of invasive breast cancer have better prognosis?
Pure mucinous, tubular, medullary, and papillary carcinomas.
What are the general staging categories for breast cancer?
Localized, regional, and distant metastasis.
What is the most influential predictor of post-treatment recurrence and death in breast cancer?
Presence or absence of metastasis to axillary lymph nodes.
What percentage of breast cancers are ER-positive?
50-85% of breast cancers are ER-positive.
What is the clinical importance of ER positivity in breast cancer?
It identifies hormone-sensitive tumors and predicts favorable response to hormone therapy.
What are the features of invasive lobular carcinoma?
Indurated, ill-defined masses with small, ovoid nuclei arranged in single-file patterns.
What is tumor angiogenesis and its significance in breast cancer?
The growth of blood vessels necessary for tumor growth and metastasis, serving as a prognostic marker.
What is the functional unit of the breast?
The terminal duct lobular unit, where lobules make milk and ducts drain it to the nipple.
What are the two epithelial layers of breast ducts and lobules?
The luminal cell layer (responsible for milk production) and the myoepithelial cell layer (responsible for milk propulsion).
What causes galactorrhea?
Milk production outside lactation caused by nipple stimulation, prolactinomas, or drugs. It is not a symptom of breast cancer.
What is the most common cause of acute mastitis?
Staphylococcus aureus, often associated with breastfeeding.
What is periductal mastitis and its primary risk factor?
Inflammation of subareolar ducts, primarily seen in smokers due to vitamin A deficiency.
What characterizes mammary duct ectasia?
Inflammation and dilation of subareolar ducts, presenting with a periareolar mass and green-brown nipple discharge.
What is fat necrosis of the breast?
Necrosis of breast fat, often related to trauma, presenting as a mass or abnormal calcifications on mammography.
What are fibrocystic changes in the breast?
Hormone-mediated fibrosis and cysts, presenting as clumpy breast tissue, often in the upper outer quadrant.
Which fibrocystic changes are associated with increased cancer risk?
Ductal hyperplasia and sclerosing adenosis (2x risk), atypical hyperplasia (5x risk).
What is an intraductal papilloma?
A benign papillary growth in a large duct, presenting as bloody nipple discharge in premenopausal women.
How is papillary carcinoma distinguished from intraductal papilloma?
Papillary carcinoma lacks myoepithelial cells and is more common in postmenopausal women.
What is a fibroadenoma?
A benign, estrogen-sensitive tumor of fibrous tissue and glands, presenting as a mobile, marble-like mass in premenopausal women.
What is a phyllodes tumor?
A fibroadenoma-like tumor with leaf-like projections, most commonly seen in postmenopausal women and potentially malignant.
What are the risk factors for breast cancer?
Female gender, age, early menarche/late menopause, obesity, atypical hyperplasia, family history, and estrogen exposure.
What is ductal carcinoma in situ (DCIS)?
A malignant proliferation of ductal cells without invasion of the basement membrane, often detected as calcifications on mammography.
What is Paget disease of the breast?
DCIS extending to the nipple, presenting as nipple ulceration and erythema, often associated with underlying carcinoma.
What is invasive ductal carcinoma?
The most common type of breast cancer, forming duct-like structures, and presenting as a mass or skin dimpling.
What are the subtypes of invasive ductal carcinoma with good prognosis?
Tubular carcinoma, mucinous carcinoma, and medullary carcinoma.
What is lobular carcinoma in situ (LCIS)?
A malignant proliferation of lobular cells without invasion, often multifocal and bilateral, treated with tamoxifen.
What is the characteristic pattern of invasive lobular carcinoma?
A single-file growth pattern due to lack of E-cadherin, with potential signet-ring morphology.
What is the most important prognostic factor in breast cancer?
Metastasis, though axillary lymph node spread is the most useful at presentation.
What are predictive factors for breast cancer treatment?
Estrogen receptor (ER), progesterone receptor (PR), and HER2/neu gene amplification.
What are triple-negative tumors?
Tumors negative for ER, PR, and HER2/neu, associated with poor prognosis and higher incidence in African American women.
What are the features of hereditary breast cancer?
Early onset, multiple tumors, and family history, often linked to BRCA1 (breast and ovarian cancer) and BRCA2 (male breast cancer).
What are the characteristics of male breast cancer?
Rare, presents as a subareolar mass, often invasive ductal carcinoma, associated with BRCA2 mutations and Klinefelter syndrome.
