Anatomy and development of the breast:

• NAC (nipple areolar complex) blood supply comes from perforators of internal mammary artery from the fourth intercostal space.
• Estrogen causes ductal proliferation; Progesterone causes glandular proliferations
• Development: Tanner stages I-V involve development of breast buds and pubic hair simultaneously
• Premature thelarche: development of breasts prior to other areas

Breast Pathology

• Accessory breast tissue: occurs along embryonic milk line and enlarges during periods of hormonal stimulation like puberty
• Pathology shows glandular tissue and receptor staining positive for estrogen progesterone
• Fibroadenoma: firm rubbery nodule, histopathology shows epithelial and stromal proliferation
• Giant fibroadenoma: solitary firm, nontender, >5cm. Presents as rapid breast enlargement with prominent overlying veins and occasional pressure-induced skin ulcerations
• Treatment includes enucleation and breast reduction
• Juvenile hypertrophy: progressive enlargement of breasts during puberty (>1500g), histopathology reveals increased stromal collagen and fat.
• Hypertrophy of the stromal content
• Thought to be from an abnormal end organ responsiveness to estrogen (rather than an increasing level of receptors or estrogen itself).
• Juvenile papillomatosis (swiss cheese disease): presents clinically similarly to fibroadenoma although pathology reveals hyperplasia and sclerosing adenosis.
• 10% can go on to develop malignancy
• Phyllodes tumor: treatment is WLE with 1cm margins.

Breast Reduction

• Patient selection: no age requirements, young patients may undergo if they have profound breast development that has physical and psychological effects
• Breast development may continue and they may need second reduction
• Wait until enlargement has stabilized for 1 year prior to surgical intervention
• Presentation of macromastia includes complaints of shoulder pain, neck and upper back pain, grooving of bra straps, rashes (interiginous).
• Trapezial hypertrophy seen
• Resection weight is not correlated with relief of symptoms (insurance companies will use resection weight as criteria for coverage)

Breast Reduction procedure and design:

• Liposuction: leaves major vessels and nerves intact, sensation, blood supply and breast feeding potential usually preserved
• Has bruising and swelling that can take >6 weeks to resolve
• Good for adipose tissue (not as great for glandular tissue), does not correct ptosis
• Vertical breast reduction: superior pedicle for areola, central breast reduction, decreased skin undermining
• There is only skin excision in one direction (decreases scar burden)
• Overall narrows breast shape, maximizes breast projection
• Can increase inframammary fold to nipple distance
• Should not use in NAC transpositions >9cm.
• Wise Pattern breast reduction:
• Allows reduction in size of areola, increase projection
• Does not decrease base width
• Can appear boxy

Pedicle: subdermal plexus preserved in each pedicle as the blood supply is superficial, this is also thought to be the primary venous drainage.

• Superior: involves resection of the tissue at base of breast (perforator from second intercostal space)
• Most likely to alter NAC sensation as it resects both medial and lateral innervations of the nipple
• Superomedial: perforators from internal thoracic artery (primarily second and third intercostal space)
• Sensation to NAC after superomedial reduction comes from terminal branches of fourth and fifth anterior intercostal nerves
• Normal sensation to NAC comes from lateral cutaneous fourth intercostal nerve
• Inferior and central pedicle: contains perforators from the internal mammary vessels from the fourth intercostal space

Free Nipple Grafts: relative indications include elevation of nipple >25 cm, smokers, and patients with diabetes

Complications

• Dusky NAC: <5% of patients, increased BMI is a risk factor
• If discovered in the operating room, release sutures and assess for hematoma or external compression, continue to assess pedicle for kinking or twisting.
• If no improvement consider free nipple graft.
• If presents late in postoperative period should observe until wound healing complete. This will then be followed by nipple reconstruction in a delayed fashion
• Most common complication of breast reduction is delayed wound healing which occurs in up to 21% of patients.
• Correlates with pre-operative breast volume, average resection weight, smoking, inversely related with patient age.
• Hematoma: correlated with hypotensive general anesthesia (recommend normotensive general anesthesia).
• Galactorrhea: post operative milky discharge from breasts from stimulation of prolactin and interruption of intercostal nerves.
• Treat with bromocriptine
• Fat necrosis after breast reduction occurs in 2-10% of patients. Risk factors for development of fat necrosis include larger BMI, larger resection weights, long suprasternal notch to nipple distance of >37cm.
• Presents has a hard lump after breast reduction or can be seen as abnormalities on mammograms.
• Risk of breast cancer:  should send specimens to pathology particularly if >40 years
• Breast reductions decrease the rate of breast cancer by approximately 30% (mastectomies 90%).
• Patients without previous history of breast cancer have an incidence of breast cancer in breast reduction specimens of 0.4%. If patients have a history of breast cancer this increases to 5.5%.
• Post surgical changes after breast reduction include fat necrosis, oil cysts, fibrosis, calcifications
• Workup consists of mammography and ultrasonography
• Scattered microcalcifications such as round spherical, punctate and diffusely scattered consistent with benign.
• Cluster, branching may be indicative of malignant lesions.

Miscellaneous

• McCune-Albright syndrome or  polyostotic fibrous dysplasia is characterized by premature puberty. This presents as benign menstruation prior to breast development. This is also associated with bony abnormalities and café au lait spots.