Introduction
Breast development is an essential component of the pubertal transformation. It is imperative for a pediatric provider to recognize normal and abnormal breast development. Although the majority of pediatric breast concerns are benign, familiarity with specific conditions is important for diagnosis and patient counseling.
Typically breast development begins at 4 to 6 weeks’ of gestational age along the anterior body wall in what is typically referred to as the “milk line” ( Fig. 14.1 ). Nipple development occurs at 8 months’ of gestation, and breast buds may be palpable at 34 weeks’ of gestation. These buds are resultant from exposure to maternal estrogen and typically regress within the first few months of life. During puberty, thelarche occurs as the ductal tissue grows because of endogenous estrogen exposure and lobular/areolar tissue expand because of progesterone exposure. , Timing of thelarche can vary by body mass index (BMI) and ethnicity; however, consensus groups have determined thelarche at age less than 8 years or no breast development by age 13 warrant investigation for normal BMI and a general population. , ,
In what follows we will discuss common conditions and variants seen with adolescent breast development.
Breast abscess
A breast abscess is a purulent, fluctuant mass. Inflammatory lesions comprise around 4% of all breast lesions in nonlactating adolescents. , It may result from local infection, epidermoid cysts, foreign bodies, trauma, nipple piercing, and folliculitis often stemming from the shaving of periareolar hair. Infants less than 2 months may develop mastitis or even an abscess from bacterial spread through the nipple ( https://www.youtube.com/watch?v=DUsHZv4rNKc ). The most common organisms identified in breast abscesses are Staphylococcus aureus, beta-hemolytic streptococcus, Escherichia coli, and Pseudomonas aeruginosa . A patient with a breast abscess typically presents with localized tenderness and induration followed by erythema and then a fluctuant mass. Associated symptoms may include fever, axillary adenopathy, and/or nipple discharge. A breast ultrasound helps to distinguish between cellulitis and a blocked duct or abscess. On physical examination, a tender, indurated, or fluctuant erythematous breast mass is typically seen. The most common location is the areolar/periareolar area. The differential diagnosis includes cellulitis and cystic breast disease. Management includes local care with warm compresses and pain relief with nonsteroidal antiinflammatory drugs (NSAIDs), acetaminophen, or acetaminophen with codeine. Antimicrobial coverage should initially include coverage for methicillin-resistant S. aureus (MRSA) until culture and sensitivity results are available ( Table 14.1 ). If the abscess becomes fluctuant or if symptoms progress/fail to resolve, aspirate for culture and sensitivity. If it continues to enlarge or fails to respond, incision and drainage (with consideration of packing) should be performed by a provider trained in the surgical treatment of the breast.
| Drug | Pediatric Dose a | Considerations |
|---|---|---|
| Immune Competent, Well Appearing, no Systemic Symptoms | ||
| Amoxicillin-clavulanate | 25 mg/kg/day PO of the amoxicillin component in 2 divided doses | |
| Cephalexin | 25–50 mg/kg/day PO divided in 3–4 doses (Max = 2 g/day) | |
| Clindamycin | 30–40 mg/kg/day PO divided in 3–4 doses (Max = 1.8 g/day) | Suggested in areas of increased MRSA |
| Immune Compromised, Ill Appearing | ||
| Nafcillin or oxacillin | 100–150 mg/kg/day IV in 4 divided doses | IV drug of choice when MRSA less likely |
| Vancomycin | 40 mg/kg/day IV in 4 divided doses | Use if high concern for MRSA or life-threatening PCN allergy |
| Clindamycin | 25–40 mg/kg/day IV in 3 divided doses | IV drug of choice if high concern for MRSA or life-threatening PCN allergy |
Breast variations
There are many variants of breast/nipple shape and size, the majority of which are benign and do not require intervention.
Tuberous breasts
Tuberous breasts are described as having a constricted breast base, decrease in breast volume, abnormal elevation of the inframammary fold, and areolar herniation. The etiology and pathophysiology are controversial; however, most agree they are embryonal in origin with anomaly of the areolar fascia. The condition manifests as a tuberous root-shaped or mushroom-shaped breast developing in early breast growth ( Figs. 14.2 and 14.3 ). This variant is seen to arise in puberty, and prevalence can be as high as 27%. There is no other testing required relevant to the condition unless a unilateral tuberous shape is noted. In this situation, ruling out an underlying breast mass is prudent. Additional caution should be taken with estrogen when given during delayed pubertal induction, as tuberous changes can occur when initiating induction at adult levels of estrogen at greater than 20 mcg/day. Management and treatment options are surgical. High levels of satisfaction are seen with surgical correction by a plastic surgeon with expertise with this particular breast variant ( https://www.youtube.com/watch?v=TeUOLEuiNjE ).
Accessory breast tissue and nipple
The most common area for accessory nipple to be located is inferior to the breast, and the most common location for accessory breast glandular tissue is in the axilla ( Figs. 14.4–14.6 ). The prevalence of accessory nipple is 1% at birth; however, accessory nipples are not often recognized until puberty. Accessory nipples can occur anywhere along the milk line and are the result of failed regression during embryonic development. , They present as darkened areolar tissue anywhere along milk lines that can often mimic dermatologic nevi. Small studies suggest that accessory nipples could coincide with renal anatomic pathology, and imaging of the complete genitourinary tract may be considered, as renal and müllerian anomalies can occur concurrently. Accessory nipples are generally asymptomatic; however, they can become painful and swollen with breastfeeding and pregnancy. Surgical removal can be performed when symptomatic ( https://www.youtube.com/watch?v=gzXRXe-g7YE ).
Macromastia (juvenile breast hypertrophy)
Macromastia ( Fig. 14.7 ), also known as juvenile breast hypertrophy, is a very rare condition with unknown prevalence. The etiology and pathophysiology are unknown; however, it is theorized that it may be the result of an inappropriate response to endogenous hormones or autoimmune mediated. The process usually occurs proximal to menarche, with bilateral rapid breast growth. Breasts may weigh up to 50 pounds each. Stretch marks often occur during rapid growth. Patients frequently report breast and upper back pain. Though no further testing is needed, ruling out the use of exogenous hormones is prudent. Additionally, many argue that the use of imaging is helpful to eliminate the notion of an underlying mass effect. Management with supportive undergarments is beneficial. Consider the use of NSAIDs for pain and progesterone or antiestrogens to slow growth. , Once breast growth is complete, referral for mammoplasty can achieve high satisfaction ( https://www.youtube.com/watch?v=fc9RsmFwyQg ).
Lipomastia
Lipomastia is the presence of excessive adipose tissue in typical breast areas before pubertal transition. Its prevalence and epidemiology are unknown, but with increasing obesity, it is often confused for premature thelarche or precocious puberty. Given that lipomastia can mimic premature puberty, careful examination to exclude premature thelarche is important . When encountering the obese patient with concern for possible premature thelarche vs. breast adiposity, the examination should be performed supine. If no palpable glandular breast tissue is under the fat pad of the chest wall, lipomastia can be confirmed. There is no treatment required, and expectant management with anticipatory guidance should be given.
Hypomastia, amastia, and athelia
Hypomastia or amastia manifests as congenital absence of breast tissue, and athelia as congenital absence of the nipple ( Fig. 14.8 ). The prevalence is extremely rare. Etiologies are thought to be destruction of the milk line during embryologic formation (Poland syndrome; Fig. 14.9 ) or chest wall trauma or radiation as a neonate. , However, these conditions can also occur with endocrine disorders associated with delayed puberty such as hypothyroidism, ovarian failure, and androgen excess, as well as chronic systemic diseases which can present as delayed puberty. The differential diagnosis should include screening for breast flattening/ironing. This is described as the harmful practice of ironing, pressing, or pounding breasts to delay growth in order to disguise the onset of puberty in a girl, which is often viewed in some communities to shield pubertal development in an attempt to protect the girls from sexual exploitation. Additionally, Poland syndrome, which results from underdevelopment or absence of the pectoralis major muscle on the hypoplastic breast side, should be considered in the differential. Testing for these conditions revolves around historical trauma, pubertal timeline, and clinical examination. Consider screening for hypothyroidism or androgen excess as appropriate. The provider should also inquire about nutritional state and start evaluation for delayed puberty if no breast development by age 13. If there is no underlying pathology, consultation for surgical augmentation may be desired once puberty is complete.
