Fiser Chapter 24 BREAST Flashcards
Breast develops from what
Ectoderm milk streak
Estrogen, progesterone, and prolactin in breast development
Estrogen -> duct development (double layer of columnar cells)
Progesterone -> lobular development
Prolactin -> synergizes estrogen and progesterone
Cyclic hormone changes in breast
Estrogen -> increases breast swelling and growth of glandular tissue
Progesterone -> increases maturation of glandular tissue, withdrawal causes menses
FSH, LH surge -> ovum release
After menopause, lack of estrogen and progesterone results in atrophy of breast tissue
Long thoracic nerve
Serratus anterior; injury causes winged scapula
Blood and nerve supply to serratus anterior
Long thoracic nerve
Lateral thoracic artery
Thoracodorsal nerve
Latissimus dorsi; injury causes weak arm pull-ups and adduction
Blood and nerve supply to latissimus dorsi
Thoracodorsal nerve
Thoracodorsal artery
Pectoralis muscle nerves
Pectoralis major: medial pectoral nerve, lateral pectoral nerve
Pectoralis minor: medial pectoral nerve
Intercostobrachial nerve
Lateral cutaneous branch of 2nd intercostal nerve
Provides sensation to medial arm and axilla; encountered just below axillary vein when performing ax dissection; can transect without serious consequences
Breast blood supply
Branches of internal thoracic artery, intercostal arteries, thoracoacromial artery, and lateral thoracic artery
Batson’s plexus
Valveless vein plexus that allows direct hematogenous metastasis of breast CA to spine
Breast lymphatic drainage
97% to axillary nodes
2% to internal mammary nodes (any quadrant can drain to internal mammary nodes)
Primary axillary adenopathy
1 is lymphoma
Breast cancer with positive supraclavicular nodes
N3 disease
Cooper’s ligaments
Suspensory ligaments; divide breast into segments
Breast CA involving these strands can dimple the skin
Breast abscess most common bacteria
Staph aureus; strep
Usually associated with breastfeeding
Breast abscess tx
Perc or I&D; discontinue breast feeding; breast pump, antibiotics
Infectious mastitis most common bacteria
S aureus most common in nonlactating women, can be due to chronic inflammatory diseases (actinomyces) or autimmune disease (SLE) -> may need to r/o necrotic cancer (need incision biopsy including skin)
Most commonly associated with breastfeeding though
Smoker with nipple piercing, presents with noncyclical mastodynia, erythema, nipple retraction, creamy discharge from nipple. On biopsy has dilated mammary ducts, inspissated secretions, marked periductal inflammation
Periductal mastitis: mammary duct ectasisa or plasma cell mastitis
-can have sterile or infected subareolar abscess
- Tx: ABX and reassurance, if typical creamy discharge is present that is not bloody and not associated with nipple retraction
- If bloody or nipple retraction or recurs, INCISIONAL BIOPSY WITH SKIN to r/o inflammatory breast CA
Lactating woman with breast cyst filled with milk
Glactocele
Tx: Aspiration or I&D
Causes of galactorrhea
- Increased prolactin (pituitary prolactinoma)
- OCPs
- TCAs
- Phenothiazines
- Metoclopramide
- Alpha-methyl dopa
- Reserpine
-Often associated with amenorrhea
Gynecomastia causes
- Cimetidine
- Spironolactone
- Marijuana
- Most are idiopathic
- 2-cm pinch
- Tx: will likely regress; may need to resect if cosmetically deforming or causing social problems
Neonatal breast enlargement due to what
Circulating maternal estrogens; will regress
Accessory breast tissue (most common in axilla)
Polythelia