Anatomy of breasts: large modified sebaceous glands within superficial fascia of the anterior chest wall.
Wt: 200-300g, 20% glandular tissue and 80% fat and connective tissue.
Composed of 12-20 lobes arranged radial fashion from the nipple.
Lymphatics: 75% regional axillary nodes (30-60 #), other route internal mammary, direct spread to mediastinum-intercostal glands, subpectoral and subdiaphragmatic. Lymphatic drainage usually flows toward the most adjacent group of nodes. Thus the concept represents basis for sentinel node mapping.
Benign breast disease
- Fibrocystic changes- cysts within ducts and increased fibrous tissue, irregular, nodular and cyclically painful breasts. Exaggeration of normal psychological response of breast tissue to cyclic levels of ovarian hormones. Occurs 20-50 years old.
- Three clinical stages: mastoplasia (pt 20’s) pain upper, outer quadrants, due to proliferation of stoma. Adenosis (pt 30’s) less pain and cystic (pt 40’s) no breast pain.
- Management: support bra, diuretics, decrease consumption caffeine and tobacco.
- Drug of choice danazol (FDA approved rx mastalgia) 100, 200, 400 mg daily for 4-6 months but no more than 6 months. If no response, then trial of bromocryptine or tamoxifen (which completes with estrogen receptor in breast.)
- Cancer risk depends upon biopsy findings
- Non-proliferative- no risk
- Proliferative- 2x risk
- Atypical- 5x risk
- Atypical + family Hx- 11x risk
- Fibroadenomas second most common. Usually adolescents and women in their 20’s. Don’t change size with meses, no pain or tenderness. Rx conservative 6 month follow-up vs. surgery. Fine needle aspiration should be performed to rule out any malignancy with either histologic or cytologic evaluation.
- Cystosarcoma phyllodes- most frequent breast sarcoma rapidly growing fifth decade of life. 1:4 is malignant. Rx benign cystosarcoma is exision with wide margin of normal tissue.
- Intraductal papilloma- bloody discharge from one nipple, perimenopausal women, and spontaneous and intermittent. Can be watery, serous or serosanguineous. Located under areola in 75%. With pressure, you should identify whether it’s a single duct or multiple ducts. With single duct, can be intraductal papilloma or cancer vs. multiple ducts most likely cancer. Rx biopsy of involved duct and surrounding tissue.
- Nipple discharge- milky-galactorrhea, multicolored and sticky-ductal ectasia, purulent-mastitis, serous/serosanguineous. Can be either intraductal papilloma, fibrocystic, or cancer.
- Fat necrosis- rare, related to trauma. Mammography stippled calcification and stellate contractions. Skin associated skin retraction similar to cancer. Rx- excisional biopsy.
- Breast cyst- variant fibrocystic changes, present in 30-50 year olds, frequent pain and tenderness which worsens premenstrually then regresses.
- Management- office needle aspiration. Mass deflates and clear fluid. No further eval.
- Bloody fluid sent cytology and biopsy, mass remains diag mammo and US. If reoccurrence restrict caffeine, OC, if recurs twice then excision.
#1 cause of cancer in women. Increase diagnosis whites > blacks, death in blacks > whites
#2 cause of death after lung cancer.
Risk: 1/50 at 50 years old, 1/24 at 60 years old, and 1/10 at 80 years old
Hereditary breasts and ovarian cancer (HBOC) gene mutation explains 5-10% breast cancer. 80% due to BRCA 1-2 gene mutation. BRCA 1-2 is responsible for preventing DNA errors, but mutated BRCA genes allow DNA errors.
- 1/3 cases of 20-29 years old
- Of women with breast < 50 years old and one close relative with breast <50 years old, mutation is present in 18%
- 45% have BRCA1 (mapped chromosome 17), 35% have BRCA2 (chromosome 13), 20% other mutations.
- BRCA positive lifetime risks
- 50% by 50 years old
- 87% by 70 years old
- Ovarian cancer by 70 years old. BRCA1 150% (40-60%) BRCA2 15% (10-20%)
Risks of HBOC:
- Personal history of early breast cancer, bilateral, in multiple sites, ovarian cancer (at any age)
- Previously indentified BRCA 1-2 mutation in family
- 1st degree relative (mother/sister) with premenopausal breast cancer
- More than 2 family members (maternal or paternal) with breast or ovarian cancer
- Ashkenazi Jewish heritage with family history of breast cancer at any age
- Family history: Cowden of Li-Fraumeni syndrome
No increased risk-adenosis, fibroadenoma, mastitis, mild hyperplasia
Slight increased risk- moderate hyperplasia, papilloma
Increased risk- atypical hyperplasia, high breast density
Mammographic breast density- 3-5 times greater risk of breast cancer in women with high breast density on mammo vs. women with low density
- Density decreased advancing age, menopause, heavier body weight, earlier childbearing
- Density increased with hormonal use
- Birad system breast density is rated category 1-4 (4 being the greatest density)
Breast cancer and endogenous hormones-
- Reproductive history- 1st term pregnancy < 30 years protective, transient increase risk in 2-3 years after delivery, greater protection with a larger number of term pregnancies, lactation minimally positive or no effect
- Oophorectomy at under 35 years old: 75% reduction in risk
Breast cancer and exogenous hormones-
- OCP neither cause nor protect
- HT- estrogen only no risk, E+P increased risk more notable with longer duration of use and correlated with increased breast density. E+P may be weak promoters but not cause of breast cancer.
Prevention of breast cancer in high risk women-
- low fat diet, exercise, ideal body weight, limit alcohol and stop smoking, limit HT use for women to 2 years use
- Prophylactic mastectomy with reconstruction > 90% breast reduction
- Prophylactic oophorectomy 75% reduction ovarian cancer and breast cancer.
- SERMS- tamoxifen-49% dec if high risk, 86% ductal hyperplasia. Raloxifene equal to tamoxifen (STAR trial) in reducing risk of invasive breast cancer, but more VTE
- Aromatase inhibitors- arimidex, Femara
- 70-80% ER + breast tumors prevented. Few side effects and better outcomes
Breast cancer screening in high risk women-
- Mother with breast cancer: begin 10 years before mother diagnosed
- Family history/BRCA+
- CBE and mammo every 6-12 months, starting 25-30 years
- Ovarian cancer screening 6-12 months, from 40 years old: CA 125, US and color Doppler
- Breast ultrasound- conjunction with mammo. Uses cystic vs. solid masses, small invasive cancers if dense breast, and vascular assessment
- MRI- Gadolinium contrast identifies neovascularity. Sensitivity 90%, performed early in menstrual cycle.
- Annual MRI- MBRCA mutatiob, 1st degree relative of BRCA carrier, radiation to chest between age 10 and 30 years, Li-Fraumeni syndrome and first degree relatives, Cowden and Bannayan- Riley- Ruvalcaba syndromes