Disorders of the Breast

Special Points in History Taking

A detailed history can provide important clues to the pathology of a breast problem. Age alters the probability of different breast disorders ( Fig. 45.2 ); in particular, the risk of malignancy rises with age. The duration of symptoms should be established at the outset; cancers are usually slow-growing, whilst cysts can appear rapidly, sometimes almost overnight. Benign conditions, such as fibroadenosis and fibroadenoma may present with lumps that fluctuate with the menstrual cycle or have decreased in size since first noticed. They are also more likely to be painful and tender than a malignant lesion.

A previous history of breast conditions, particularly malignancy, cysts or fibrocystic change, can be an indicator of the nature of a current breast problem. Aside from high risk predisposing germline gene mutations, the greatest single risk factor for breast cancer is a previous history of the condition, however long ago (1% risk per year)— Box 45.2 ). There is some evidence that patients with recurrent benign breast disorders are at greater risk of cancer. If cancer is confirmed, it is important to establish the patient’s menopausal status as this influences future treatment decisions. If this is unclear, serum follicle-stimulating hormone and oestradiol levels should be measured.

Trauma from seatbelt injuries is common and patients should be asked whether bruising of the breast was followed by the appearance of a lump.

Drug history , particularly of the oral contraceptive pill (OCP) or hormone replacement therapy (HRT), should be recorded, including the type, duration and how recently the drug has been used. These drugs modulate the hormonal environment of breast tissue and tend to increase the risk of breast cancer. Other hormone-related risk factors for cancer include late age at first full-term pregnancy, lower parity (number of pregnancies), early age of menarche and late age of menopause. Enquiry should be made about a family history of breast or ovarian cancer, including number of first- and second-degree relatives, age of onset and bilaterality. Some families have mutations in the tumour suppressor genes BRCA1, BRCA2, PALB2 and others, which can strongly predispose to breast and other cancers. Increasing alcohol consumption is fuelling a rise in the incidence of breast cancer.

Examination of the Breasts

There are several accepted methods for examining the breasts; one is shown in Fig. 45.3 . All areas of the breast must be examined, with particular attention to the axillary tail and retroareolar regions. Breast examination involves six distinct manoeuvres:

• observation with the patient sitting up;

• observation with the patient raising and lowering her arms;

• examination of the nipples;

• systematic palpation of each breast;

• palpation of axilla and supraclavicular fossa;

• general examination for signs of distant metastases.

During inspection, the signs to be looked for are listed in Fig. 45.1 .

Palpation may be done circumferentially using the flat of one hand, starting at the nipple then moving in progressively larger circles; radially from the nipple outwards, like the spokes of a wheel; or by sectors , examining each quadrant in turn. Axillary lymph nodes are palpated, whilst the examiner’s other hand supports the patient’s arm (see Fig. 45.3G and H ). This helps relax the muscles and aids assessment of the nodal groups ( medial, lateral, anterior, posterior and apical ). Note that clinical assessment of axillary nodes is unreliable, with a 30% false positive and a 30% false negative rate.

A history of nipple discharge can often be confirmed by pressure over the appropriate sector near the areola. Discharges not obviously blood-stained should be tested for blood using urinalysis dipsticks. In all cases, a smear preparation should be examined for cytological abnormalities.

Lumps

The differential diagnosis of a discrete breast mass is:

• cyst

• fibroadenoma

• focus of fibrocystic change or fibroadenosis

• fat necrosis (rare)

• carcinoma

During the examination, the patient needs to point out any lump she is worried about. The normal breast has a wide range of textures, from soft through nodular, to hard, so the texture of the rest of the breast must be taken into account. When a lump is found, its characteristics should be defined ( Box 45.3 ), in particular whether it is discrete or dominant or whether it is an area of nodularity or ‘thickening’. If there is a discrete mass, does it appear benign or suspicious for malignancy? (Characteristic signs of cancer are shown in Fig. 45.4 ). Note that even for breast specialists, clinical examination has a low sensitivity (i.e., ability to detect real abnormalities) of 65% to 80%. In one clinical evaluation system, increasing levels of suspicion are graded E1 to E5; an E3 designation may prompt a core biopsy even if radiological findings are not suspicious. Only 3% of breast cancers occur under the age of 30 years but a discrete lump in a patient over 65 years is a cancer until proved otherwise.

BOX 45.3

Clinical Characteristics of a Breast Lump

• Solitary or multiple

• Size—in centimetres

• Location—quadrant of breast or clock face

• Contour—smooth and round/ovoid (likely to be benign) or firm/hard (probable malignancy)

• Mobility—mobile (likely to be benign) or fixed (probable malignancy)

• Associated changes—skin/nipple retraction, skin tethering, bloody nipple discharge, erythema

• Axillary lymphadenopathy—enlarged and mobile or enlarged and fixed

Skin tethering (as opposed to direct infiltration) can be a subtle sign and is accentuated by raising the arms to put the breast suspensory ligaments under tension. Deep fixation can be assessed by checking the mobility of the lump over pectoralis major with the muscle relaxed and then tensed.

Imaging

Mammography (breast radiography) is an important method of radiological assessment of the breasts. In women over 40 years, it has a sensitivity of 88% for carcinoma. It is less sensitive in younger women because the breast tissue is denser, and is rarely performed below 35 years.

During mammography, the breast is compressed firmly in the machine. This spreads the tissue to an even thickness to give correct exposure for all the breast tissue to make it easier to detect any mass lesion. Radiological views are taken in two directions, mediolateral oblique and craniocaudal. Localised compression views can reduce the problem of superimposed structures simulating a mass. Focused magnified views can better display any abnormal area. Full digital mammography, which permits postprocessing enhancement of the image, has nearly replaced film mammography.

Features looked for on a mammogram include:

• the presence of a mass lesion

• microcalcification

• architectural distortion

• asymmetry

• skin thickening

• lymph nodes

A typical carcinoma appears as a spiculated mass lesion (dense centre with radiating lines), which may have malignant-type fine linear or granular microcalcification ( Fig. 45.5 ). Fine granular microcalcification within a spiculate lesion is virtually pathognomonic of cancer. Tumours as small as 2 to 3 mm are sometimes detectable radiologically, long before they become palpable.

Benign-type microcalcification is coarse and ‘chunky’ ( Fig. 45.6 ). Fine branching microcalcification is characteristic of ductal carcinoma-in-situ (DCIS) . Architectural distortion and asymmetry are subtle radiological signs, but should be viewed with suspicion.

Ultrasound has long been used to distinguish solid lesions from cysts and has a specificity of 100% for this. Modern B-mode ultrasound demonstrates breast anatomy in great detail and is complementary to mammography. Benign lesions can be distinguished from malignancy with a sensitivity for cancer of at least 85%. Ultrasound can accurately measure the size of a cancer ( Fig. 45.7 ) and can guide percutaneous needle biopsies and cyst aspiration ( Fig. 45.8 ).

The strength of breast imaging comes from performing mammography and ultrasound together, as the physical characteristics tested by the two techniques are different. The information acquired by mammography results from attenuation of the x-ray beam through breast structures, whilst ultrasound tests the reflectivity of a pulsed ultrasound beam (of about 12 mHz), caused by subtle attenuation changes at tissue interfaces within the breast.

Biopsy

Most palpable and all nonpalpable image-detected masses are biopsied under image guidance, as are suspicious areas of calcification. Fine-needle aspiration cytology (FNAC) specimens are rarely used for tissue diagnosis now ( Box 45.4 ). FNAC has a sensitivity of 95% for detecting malignancy, but cannot distinguish between in situ and invasive cancers. By contrast, core biopsy has a sensitivity of 98%. The tissue architecture is preserved so that invasion can be confidently diagnosed on histology and tumours can be pathologically graded. After core biopsy, patients need to return later for the results as the pathology has to be read after the specimen has been fixed. This has the advantage that any bad news can be broken in a phased manner. If needle biopsy is negative or equivocal, a discrete lump should be completely excised with a wide margin of apparently normal breast tissue and the specimen examined histologically. This procedure, excision biopsy, can also form the first step in controlling local disease.

Eczematous lesions suspicious for Paget disease of the nipple can be ‘punch’ biopsied under local anaesthesia in the clinic.

Introduction

In Western societies, breast cancer is the leading cause of death in European women. About 1 in 8 to 10 women will develop breast cancer (i.e., a lifetime risk of ∼10%–12%) and ∼1 in 18 will die from it. In the United Kingdom, more than 50,000 new cases are diagnosed annually and ∼12,000 women die each year. Worldwide, there are about half a million deaths from breast cancer each year, but despite this increasing global incidence, mortality rates have gradually fallen with earlier diagnosis and improved treatments, including advances in hormonal and targeted therapy. Around 27% of cases in the United Kingdom are preventable.

Risk Factors