PUBERTY

The transition from childhood to adolescence is regulated by hormones secreted by the hypothalamic–pituitary axis. During puberty there is a rapid spurt in growth, accounting for approximately 25% of the final adult height. Secondary sexual characteristics develop and sexual awareness is aroused.

The age of puberty varies and parents and teenagers often worry about what they perceive as a delayed growth spurt. A number of factors determine the onset of puberty. Over the past 150 years there has been a progressive fall in the age of the first menstrual period (menarche). This is thought to reflect the effects of improving nutrition and general health on the onset of puberty. There is evidence that body weight is an important trigger for puberty: moderately overweight girls tend to enter puberty earlier than their lean contemporaries. Abnormal weight loss (such as occurs with anorexia nervosa or a debilitating illness) causes delay of the menarche or cessation of established periods altogether (amenorrhoea).

Adolescent development can be assessed using pubertal milestones defined by Tanner (Fig. 8.1). For girls this is based on breast development and the growth of pubic hair. Puberty in girls begins between 8 and 13 years of age. The average age of the menarche is 12.5 years and most girls will have menstruated by the age of 14.5 years.

Fig. 8.1 Stages of breast development. Development from the preadolescent stage (1) begins initially with a widening of the areola and the development of subareolar tissue (2). Progressive expansion occurs (3–4) until adult size is attained (5).

Hormonal changes in puberty

Puberty is established by the activation of the neuroendocrine axis. The cerebral cortex plays a central role in the initial activation of the hypothalamus, which stores gonadotrophin-releasing hormone (GnRH). This hormone is released into the hypothalamo-hypophyseal portal system and is carried to the anterior lobe of the pituitary gland where it stimulates the release of sex hormones. During childhood, GnRH secretion is inhibited and loss of this inhibition signals the onset of puberty (Fig. 8.2). Pulsatile release of GnRH provides the signal for the pulsatile release of follicle-stimulating hormone (FSH) and luteinising hormone (LH) from the pituitary gland which, in turn, stimulates the gonads. The hormonal products of the female gonads then exert their specific influences on the reproductive organs and induce the development of secondary sexual characteristics. Breast growth (telarche) in women is followed by the menarche and the establishment of the menstrual cycle.

Fig. 8.2 The hypothalmic–pituitary–gonadal axis. In childhood, gonadotrophin-releasing hormone (GnRH) secretion is inhibited (left). Loss of GnRH inhibition induces puberty and provides the signal for the release of follicle-stimulating hormone (FSH) and luteinising hormone (LH). FSH and LH stimulate the gonads and exert cyclical changes in the uterine endometrium (right).

Pubic hair growth

In both males and females, growth of the pubic hair is regulated by adrenal androgens, with an additional contribution of testicular androgen in the male. In females, the pattern of pubic hair growth has a characteristic inverted triangular appearance (Fig. 8.3).

Fig. 8.3 Pubic hair development. Development from the preadolescent (1) begins with the growth of sparse straight hair along the medial borders of the labia (2). Further growth of darker coarser curlier hair continues (3–4) until the typical inverted triangular distribution of the adult female is seen (5).

Ovarian and menstrual cycle

The cyclical release of FSH and LH from the pituitary is reflected in serum concentration changes. Ovulation occurs in response to these changes and this in turn regulates cyclical changes in the uterine endometrium (Fig. 8.4). In each cycle, a few ‘selected’ dormant ovarian follicles become responsive to FSH, with usually only a single dominant follicle maturing to the point of ovulation (Fig. 8.5). The primordial follicle consists of a large oocyte surrounded by a flattened follicular epithelium. In the few responsive follicles, FSH stimulates the proliferation of granulosa cells which secrete an oestradiol-rich fluid that accumulates in the follicle (the antrum). As the follicle grows, it is surrounded by a specialised layer of thecal cells which are derived from the ovarian stroma. The responsive follicle grows to attain a preovulatory size of 2–3  cm. In midcycle there is a surge of both FSH and LH (Fig. 8.4); the LH surge is thought to trigger the events leading to the extrusion of the ovum from the ovary.

Fig. 8.4 Physiological changes associated with the menstrual cycle.

Fig. 8.5 Development of a mature ovarian follicle.

Extrusion of the ovum leaves behind the corpus luteum (Fig. 8.4), which secretes progesterone, the dominant sex hormone in the second phase of the ovulatory cycle. The granulosa cells of the corpus luteum express LH receptors which are also capable of binding human chorionic gonadotrophin (HCG), a hormone secreted by the fetal syncytiotrophoblast. In the absence of fertilisation, HCG does not appear in the circulation, and by about the 23rd day of the cycle, the corpus luteum starts to atrophy. Progesterone levels fall, allowing the re-expression of FSH secretion and the initiation of another cycle. If conception has not occurred, menstruation commences. This is caused by an intense vasospasm in the arterioles feeding the superficial layers of the endometrium, which causes hypoxic necrosis of this tissue. The tissue is then expelled through the vagina.

Climateric and menopause

By about the age of 40 years, the number of functional oocytes has fallen to the point where sex hormone synthesis is reduced. This signals the onset of the climacteric, which over a period of years culminates in the cessation of menstruation (the menopause). Initially, FSH levels increase in an attempt to stimulate follicular ripening; later, anovulatory cycles develop with irregular menstrual bleeding; finally, at about the age of 50 years, menstruation ceases. Loss of hormonal feedback results in high serum levels of FSH and LH (Fig. 8.6). Serum levels of these hormones are used as a test for the climacteric and menopause. The decline in oestrogen production results in atrophy of the breasts, genital organs and bone. Vasomotor instability may result in hot flushes.

Fig. 8.6 Loss of hormonal feedback in the menopause. The hypothalamus tries to compensate for the falling oestrogen level by increasing production of follicle-stimulating hormone (FSH) and luteinising hormone (LH).

LYMPHATIC DRAINAGE OF THE BREAST

As breast cancer spreads to regional lymph nodes, it is important to appreciate lymphatic drainage because the discovery of affected nodes implies a more serious prognosis and influences the mode of treatment. In general, the lymphatics follow the blood supply, yet there is a free connection between the lymphatics of the one breast, and sometimes with the other. Nonetheless, the lateral part of the breast usually drains towards the axillary group of nodes and the medial half towards the internal mammary chain. The axillary nodes are arranged into five groups, each of which must be examined (Fig. 8.11). The vast interconnection of lymphatics predisposes to widespread metastatic spread, with nodes in the opposite axilla becoming affected. Even the abdominal nodes may be involved.

Fig. 8.11 Diagrammatic representation illustrating the position of the axillary lymph nodes.

FUNCTION OF THE BREAST

During puberty, glandular growth is primarily under the trophic influence of oestradiol and progesterone. Throughout pregnancy, the breasts enlarge further under the influences of rising concentrations of oestrogens, progesterone, placental lactogen and prolactin secreted by the anterior pituitary. A darkish ring (secondary areola) appears around the areola during pregnancy. Suckling by the newborn child stimulates a neuroendocrine reflex that causes further release of prolactin as well as oxytocin (from the posterior pituitary). Oxytocin (which also has a uterine-contracting action) stimulates contraction of the myoepithelial cells surrounding the lobules and lactiferous ducts, causing the expression of milk (Fig. 8.12). The effect of sucking on the nipple sustains lactation. Feeding mothers produce approximately 1 litre of milk daily. When the child is weaned, the sucking reflex is lost and lactation dries up.

Fig. 8.12 Sucking sends an afferent stimulus to the anterior and posterior pituitary, resulting in the release of prolactin and oxytocin.

PAIN

Throughout the menstrual cycle there are cyclical, trophic and involutional changes in the glandular tissue. This dynamic response of the tissue to changes in hormones may cause breast pain and tenderness which fluctuates predictably with the menstrual cycle, usually more towards the end of a cycle. A painful breast in the first few months of lactation is almost always due to a bacterial infection of the gland and is characterised by fever as well as redness and tenderness over the infected segment. Ask about local trauma, as fat necrosis may cause pain, and also consider thrombophlebitis of the veins (Mondor’s disease).

DISCHARGE

Patients may present with an abnormal nipple discharge. Determine whether the fluid is clear, opalescent or bloodstained. In men, and women who have never conceived, a discharge is always abnormal. However, after childbearing, some women continue to discharge a small secretion well after lactation has stopped. The inappropriate secretion of milk (galactorrhoea) is caused by a deranged prolactin physiology. A blood discharge should always alert you to the likelihood of an underlying breast cancer.

BREAST LUMPS

A patient may present after discovering a breast lump by self-examination. This discovery causes great alarm because the patient will usually associate the lump with breast cancer.

INSPECTION

The patient should undress to the waist. Position yourself in front of the patient, who should be sitting comfortably with her arms at her side (Fig. 8.13). Note the size, symmetry and contour of the breasts, the colour and venous pattern of the skin. Observe the nipples and note whether they are symmetrically everted, flat or inverted. If there is unilateral flattening or nipple inversion, ask whether this is a recent or long-standing appearance. In fair-skinned women, the areola has a pink colour but darkens and becomes permanently pigmented during the first pregnancy. Ask the patient to raise her arms above her head and then press her hands against her hips (Figs 8.14, 8.15). These movements tighten the suspensory ligaments, exaggerating the contours and highlighting any abnormality. In men, the nipple should lie flat on the pectoralis muscle.

Fig. 8.13 Initially, inspect the breast from the front with the patient sitting with her arms comfortably resting at her sides.

Fig. 8.14 To accentuate any asymmetry of the breast ask the patient to raise her arms above her head.

Fig. 8.15 Another technique for accentuating the breast contours is by pressing the hands against the hips.

ABNORMALITIES ON INSPECTION

In normal women there may be some asymmetry of the breast and nipples, ranging from unilateral hypoplasia to a mild but obvious asymmetry (Fig. 8.16). You may be struck by an obvious lump (Fig. 8.17), retraction or gross deviation of a nipple (Fig. 8.18), prominent veins or oedema of the skin with dimpling like an orange skin (peau d’orange). Abnormal reddening, thickening or ulceration of the areola should alert you to the possibility of Paget’s disease of the breast, a specialised form of breast cancer (Fig. 8.19). Male gynaecomastia is an important physical sign and may be spotted on inspection as a swelling of the areola or, in more florid cases, the development of obvious breasts (see Ch. 9).

Fig. 8.16 Asymmetry of the breast.

Fig. 8.17 An obvious breast lump.

Fig. 8.18 Signs suggestive of breast cancer. Nipples may be everted, flat or retracted.

Fig. 8.19 Typical appearance of Paget’s disease of the breast with reddening and scaling of the areolar skin.

BREAST PALPATION

During the chest examination the patient will be lying on the examination couch with her arms resting comfortably at her side or held above her head. Palpate the breast tissue with the palmar surface of the middle three fingers, using an even rotary movement to compress the breast tissue gently towards the chest wall (Fig. 8.20). Examine each breast by following a concentric or parallel trail that creates a systematic path that always begins and ends at a constant spot (Fig. 8.21). An obsessive and systematic exploration of all the breast tissue ensures that small lumps which could be easily missed are not. If the breasts are abnormally large or pendulous, use one hand to steady the breast on its lower border while palpating with the other. The texture of normal breast tissue varies from smooth to granular, even knotty; only experience will teach you the spectrum of normality. Texture may also vary with the menstrual cycle; nodularity and tenderness often increases towards the end of a cycle and during menstruation. Remember that breast texture is normally symmetrical and a comparison of the two breasts may help you to judge whether an area is abnormal or not.

Fig. 8.20 Palpate the breast with the middle three fingers, rotating around the point of contract while pressing firmly but gently towards the chest wall.

Fig. 8.21 Trace a systematic path either by following a concentric circular pattern (left) or examining each half of the breast sequentially from above down (right).

To examine the axillary tail of Spence, ask the patient to rest her arms above her head. Feel the tail between your thumb and fingers as it extends from the upper outer quadrant towards the axilla (Fig. 8.22). If you feel a breast lump, examine the mass between your fingers and assess its size, consistency, mobility and whether or not there is any tenderness.

Fig. 8.22 Examine the tail of Spence with the patient’s arms resting above the head. Use your thumb and first two fingers to trace the extension of breast tissue between the upper outer quadrant and the axilla.

In men, palpation helps distinguish true from ‘pseudo’ gynaecomastia (obesity with fatty breast). In true gynaecomastia a disc of breast tissue can be felt under the areola. Unlike fat, breast tissue has a distinctly lobular texture and may be tender to palpation.

NIPPLE PALPATION

Hold the nipple between thumb and fingers and gently compress and attempt to express any discharge (Fig. 8.23). If fluid appears, note its colour, prepare a smear for cytology and send a swab for microbiology.

Fig. 8.23 Inspection of the nipple.

LYMPH NODE PALPATION

The axillae can be palpated with the patient lying or sitting. When examining the left axilla in the sitting position, the patient may rest her (or his) left hand on your right shoulder while you explore the axilla with your right hand. Alternatively, there are different techniques for exposing the axilla. You may choose to abduct the arm gently by supporting the patient’s wrist with your right hand and examining with the other hand (Fig. 8.24). The opposite hands are used to examine the other axilla. Slightly cup your examining hand and palpate into the apex of the axilla for the apical group of nodes. Small nodes may be felt only by rotating the exploring fingertips firmly against the chest wall. Next, feel for the anterior group of nodes along the posterior border of the anterior axillary fold, the central group against the lateral chest wall and the posterior group along the posterior axillary fold. Finally, palpate along the medial border of the humerus to check for the lateral group of nodes and inspect the infraclavicular and supraclavicular spaces for lymphadenopathy. If you feel nodes, assess the size, shape, consistency, mobility and tenderness.

Fig. 8.24 Exposing the axilla by abducting the arm and supporting it at the wrist.

ABNORMAL PALPATION

Breast abscess (mastitis)

This usually occurs during lactation and is generally caused by blockage of a duct. The temperature is raised and the skin of the infected breasts inflamed (Fig. 8.25). Palpation may reveal an area of tenderness and induration. If an abscess forms, you usually feel an extremely tender fluctuant mass.

Fig. 8.25 Erythema overlying an area of mastitis.