Mastalgia (breast pain)

This is usually cyclical. Pain occurs early in the menstrual cycle and worsens to reach a peak just before menstruation, easing with the start of the period. Mild pain may affect the upper outer quadrants of the breast, causing minor symptoms. In severe cases, the breast may be engorged, tender and heavy.

Pain occasionally occurs in postmenopausal women, often related to hormone replacement therapy (HRT). Pain may be in one or both breasts. Clinical findings, apart from tenderness and occasionally nodularity, may be normal.

Breast lumpiness and lumps

It is vital, but sometimes difficult, to distinguish whether a breast lump is part of a diffuse lumpiness or a discrete, isolated lump. The diagnosis may be influenced by whether the lump is painful and/or the age of the patient (Table 10.1).

Table 10.1 Likely diagnosis of discrete breast lumps at different ages

The triple approach (physical examination, mammography/ultrasound and fine-needle aspiration cytology) enables a diagnosis to be made in most patients. Mammography is unhelpful in women under 35 years of age because the breasts are frequently too dense for small lesions to be seen.

Nipple discharge

Green or milky discharge is usually harmless. Clear or bloodstained discharge may indicate a duct papilloma and occasionally an underlying malignancy.

Breast abscess

This condition is a complication of breastfeeding caused by Staphylococcus aureus. The bacteria may get into the breast through cracks in the nipple during feeding. Initially a segment of the breast becomes inflamed with cellulitis. There is then a rapid build-up of pus with necrosis of local breast tissue, producing an abscess in a short space of time. A tender segment is found in the lactating breast, often with surrounding cellulitis. If detected early, antistaphylococcal antibiotics (e.g. flucloxacillin) may prevent abscess formation.

Once an abscess has formed, the pus must be released. It is usually possible to treat lactational breast abscesses by aspiration (repeated if necessary), though incision and drainage is sometimes required.

Epidemiology and aetiology

Breast cancer was, until recently, the commonest cancer to affect women in the Western world. In the UK, there were 47 695 new cases in 2008.

There is variation within various ethnic cultural groups with American Jews and nuns having a higher incidence than, for example, Mormons and American Indians. Breast cancer incidence is increasing, with approximately one woman in eight in 2008 developing the disease in the UK.

The risk factors for breast cancer are listed in Table 10.2.

Table 10.2 Risk factors for breast cancer

Age

Breast cancer is rare under the age of 35 (Fig. 10.1).

Figure 10.1 Age and risk of breast cancer.

Natural history

It takes several years for most breast cancers to become palpable, and blood-borne dissemination occurs at an early stage. Nearly one-quarter of patients who have no tumour in regional lymph nodes at the time of removal still relapse later due to distant metastatic disease. This figure rises to half to three-quarters if regional nodes are involved. This provides the rationale for detecting early cancers by screening.

Staging and prognosis

The TNM classification of breast cancer is shown in Table 10.3, and the prognosis in Table 10.4.

Table 10.3 TNM classification of breast cancer

Invasive breast cancer

The histological types of invasive breast cancer are summarised in Table 10.5.

Table 10.5 Relative frequency of histological types of breast cancer

Most breast cancers are associated with fibrous tissue proliferation (scirrhous). Consequently, the tissues surrounding the growth contract clinically. Dimpling of the skin and indrawing of the nipple may be seen. The majority of breast cancers are adenocarcinomas arising from the epithelium of the ducts and lobules (ductal and lobular types). The degree of differentiation of the tumour determines the grade:

Most breast cancers tend to express oestrogen receptors, which can be measured by immunohistochemistry, and cancers are labelled either oestrogen receptor positive or negative. Receptor positive cancers tend to respond to hormonal therapy and have a better prognosis. Some cases have receptors for HER2. Treatments with biological therapies may be used in this case.

Carcinoma in situ

There are two forms:

DCIS is subdivided into commode, solid, cribriform and micropapillary patterns.

Commode DCIS is associated with micro-invasive foci and lymph node metastases. Because necrosis and microcalcification are common and seen on mammography, DCIS is detected increasingly commonly. LCIS has no microcalcification and therefore may not be detected early. 10–30% of patients with LCIS and 30–50% of those with DCIS go on to develop invasive cancer. LCIS may occur in either breast and is a marker of increased risk of diffuse bilateral disease, compared with DCIS, which remains in the ipsilateral breast and is confined to the same quadrant from which the biopsy that yielded the diagnosis was taken.

Table 10.5 shows the relative frequency of the histological types of breast cancer. Ductal with productive fibrosis is the commonest form. Lobular carcinomas have a high propensity for bilaterality, multicentricity and multifocality and have a particular propensity for metastasising to membrane structures, for example the peritoneum, pleura and meninges.

History

A detailed history should be taken which should include known risk factors, namely family/menstrual and reproductive history, hormonal use and previous breast cancer or breast disease.

Examination

Inspection and palpation of the entire breast and lymph node areas is mandatory. The breast is examined with the patient sitting facing the examiner with the arms first at the side then raised above the head and then placed on the hips to both relax and contract the pectoral muscles. The doctor assesses asymmetry, visible lumps, erythema, peau d’orange, contour flattening, skin tethering (puckering), abnormal fixation, retraction and altered axis of the nipples or obvious gross ulceration. Skin retraction may also be determined by asking the patient to lean forward (Fig. 10.3). The supraclavicular, infraclavicular and axillary lymph nodes should be examined with the examiner taking the weight of the patient’s arm, either on the shoulder or opposite arm (Fig. 10.4). Palpation of the breast is performed in the supine position with the patient’s hand behind the head initially and then at the side. Examine the whole breast, from sternum to clavicle, latissimus dorsi to rectus sheath. Examination occurs one quadrant at a time with the flat of the hand followed by the nipple/areola area. The breast lump should be categorised by its position, size, consistency and any fixation to deep or superficial structures. Mobility should be assessed. If the patient complains of discharge, an attempt to reproduce this should be made (Table 10.6).

Figure 10.3 Leaning forward to demonstrate any skin retraction.

Figure 10.4 Examination of the axillary nodes.

Table 10.6 Models of presentation of breast cancer

Imaging

Tissue diagnosis

Carcinoma in situ

Treatment varies from segmental excision with or without radiotherapy to simple mastectomy for multifocal disease and patients who are at risk of local recurrence. Patients are followed up regularly by mammography and clinical examination. If, after local treatment, recurrent disease occurs, mastectomy is advised. LCIS is often multicentric and bilateral. Patients can either be observed closely as the risk of invasive ductal cancer is low, or undergo a curative bilateral mastectomy.

Stages I–II invasive cancer

Radical surgical resection does not enhance long-term survival because of micrometastases. The aims of surgery are therefore local control and, where possible, breast conservation. Local control is achieved by complete removal of the tumour and adjuvant local radiotherapy with or without systemic therapy. Breast-conserving surgery involves removal of the tumour but leaving a better cosmetic result (wide local excision or quadrantectomy). For centrally placed lesions greater than 4 cm in diameter, mastectomy is recommended.

Assessment of the axillary lymph nodes is essential for management and is a marker of prognosis. The presence of nodal metastases implies systemic dissemination of the cancer and adjuvant chemotherapy or hormonal therapy should be considered. The axilla can be cleared surgically (therapeutic) or nodes simply sampled. Axillary sampling has the advantage of being a lesser operation than clearance. However, if the nodes are positive, a cleared axilla needs no further treatment but a sampled axilla will require radiotherapy. See also sentinel node biopsy.

Stage III disease

Preoperative neo-adjuvant chemotherapy may reduce tumour size before mastectomy for stage III disease and for inflammatory carcinoma. Further treatment depends on the menopausal state of the patient.

Adjuvant therapy

Metastatic disease

Surgery and radiotherapy are used for local control. Combination chemotherapy, principally the CMF (cyclophosphamide, methotrexate and fluorouracil) regime, may produce remission in up to 70% of patients. Seventy-three per cent of patients with metastatic disease have skeletal metastases, which may present as bone pain or pathological fractures, particularly the femur. These should be orthopaedically treated and followed by radiotherapy. Pain from metastases can be controlled by radiotherapy. Treatment with bisphosphonates may reduce the progression and morbidity associated with bony metastases, even if not associated with hypercalcaemia. Pleural and lung metastases may cause symptomatic pleural effusions managed by aspiration and occasional pleurodesis for reaccumulations. Pleural irritant, for example tetracycline or bleomycin, may be instilled into the pleural cavity to produce pleurodesis. Prognosis is poor, with a median survival between 6 and 15 months. Cerebral metastases, causing symptoms of raised intracranial pressure or focal neurological problems, may be treated with combined therapy which may include surgery, radiotherapy or chemotherapy, with some success. Spinal cord compression resulting in hemiparalysis requires early diagnosis and urgent treatment. Surgical decompression may be appropriate for patients with posteriorly placed lesions or continued progression of disease in spite of radiotherapy.

Male breast cancer

This occurs in less than 1% of all cases and is associated with high endogenous levels of oestrogen, preceded by gynaecomastia in 20% of patients. Risk factors include testicular feminisation, Klinefelter’s syndrome (XXY), oestrogen therapy, irradiation and trauma. The prognosis is the same as for female breast cancer although it tends to present late. Treatment options are similar.

Paget’s disease

Paget’s disease presents as a chronic, eczematous eruption of the nipple confused with eczema and is almost always associated with underlying carcinoma.

Inflammatory breast carcinoma

This is a rare variant. It is rapidly progressive and characterised by erythema, peau d’orange and skin ridging with or without any mass. Unlike other cancers, it presents with pain. Dissemination of cancer cells through the lymphatics results in a diffusely enlarged breast. If these cells remain within the superficial lymphatics and blood cells, telangiectatic carcinoma may arise with numerous purple papules and haemorrhagic, vesicle-like lesions covering the breast. If associated with fibrosis, a diffuse, thickened lesion occurs (carcinoma en cuirasse).

Malignant phylloides tumour

The name is derived from its fleshy, leaf-like appearance. Histologically, malignant phylloides tumours provide a spectrum of disease from sarcomatous malignancy to fibroadenoma. Despite histological confirmation, the behaviour is difficult to predict but prognosis is generally good. Clinically, they are often large, painless and mobile within the breast, which develops, with enlargement, a characteristic teardrop appearance. Treatment is wide excision but local recurrence can occur.