The majority of breast lumps are noticed by the patient themselves, a smaller number by nursing or medical staff examining the breasts.
Most lumps measuring 1.5 cm or more are palpable.
Impalpable breast lumps are detected by population/family history screening mammography, or mammography undertaken as part of follow-up following treatment for breast cancer. Occasionally, impalpable abnormalities are picked up as incidental/unexpected findings when mammography is being undertaken for the evaluation of symptoms/clinical signs, thus emphasising the importance of careful assessment of all breast tissue when investigating any symptoms.
Some breast lumps present as a result of overlying skin changes, such as skin puckering or in-drawing of the nipple.
Advanced breast cancer may present with skin oedema – the so-called peau d’orange appearance as it resembles orange skin.
Nipple discharge can be a presenting symptom of breast cancer, ductal carcinoma in situ (DCIS) or of benign breast lumps, such as intraduct papillomas. Intraduct papillomas are usually impalpable.
Clinical examination of the breast should begin with visual inspection, preferably with the women sitting upright with her arms on her hips then elevating her arms above her head. This will reveal any asymmetry or skin changes. She should then lie supine and the breasts be examined with flat fingers in all areas. The axillae can then be examined – the woman’s arm should be bent at the elbow and supported by the non-examining hand of the examiner so that the muscles bordering the axilla are relaxed and the axilla can be palpated for masses, especially enlarged lymph nodes which may signify metastatic disease.
Breast cancers usually feel firm and may be tethered to skin or muscle. Fibroadenomas or cysts are well-defined, mobile and usually softer in texture. Fibroadenomas used to be known as ‘breast mice’ as they move away from the palpating fingers so readily. However, breast cancers may also be well-defined, mobile and relatively soft. Cysts may be compressible.
Young women under 40 are often found to have nodularity without a focal lump on clinical examination and ultrasound will be normal or show diffuse benign breast change, such as a prominent ductal pattern
Fibrocystic Breast Change
Lumpy, tender breasts occur from changes in the glandular and stromal (connective) tissues of the breast. These changes are related to the menstrual cycle and the hormones, oestrogen and progesterone.
In the luteal phase (day 15-20), cells of the lobule develop vacuoles and secretions are visible in the ducts.
In the secretory phase (day 20-27), the tissues within the lobule become oedematous and there is venous congestion. These changes may present clinically as pre-menstrual lumpiness and tenderness.
A wide variety of epithelial and stromal changes may be found pathologically, including fibrosis, and dilatation of acini within terminal ductal lobular units (TDLU) to produce cysts, or dilatation of interlobular ducts to produce duct ectasia.
Common in women under age 40
Fibroadenomas are typically well-defined and may be lobulated. They are homogeneous in echo texture and usually cast acoustic enhancement behind them on ultrasound. They are often wider than they are tall and can typically be differentiated from breast cancers (usually more hypoechoic, cast dense acoustic shadowing distally, and are taller than they are wide on ultrasound). Core biopsy will establish the diagnosis of fibroadenoma. It does not require surgery unless it grows rapidly, or the patient requests excision.
Breast cysts are very common; peak prevalence in women is 35-50 years. In younger women they tend to be uncomplicated and there is a familial association. Most cysts form in the terminal ductal lobular unit due to dilatation of lobular acini.
They may be part of normal involutional process: as lobular epithelium atrophies, acini coalesce, producing fluid filled spaces. They probably form as a result of imbalance of secretion and resorption of lobular secretions rather than duct obstruction.
Cysts may be solitary or multiple. Cysts may be aspirated under US control if painful.
25% of all palpable and non-palpable dominant masses on mammography will be cysts on ultrasound.
20% of asymptomatic women with dense breasts will have cysts.
Ultrasound is highly reliable with an accuracy 98-100% overall, but is less specific for cysts with atypical appearances.
Phyllodes tumours are rare fibroepithelial neoplasms that are mostly benign, but some may have malignant potential. Up to 20% recur locally after excision. In the more malignant lesions it is the sarcomatous element which recurs and almost 25% of these subsequently metastasise. Initial management of phyllodes tumours is wide local excision.
Occurrence is most common between the ages of 40 and 50, prior to the menopause. This is about 15 years older than the typical age of patients with fibroadenoma, a condition with which phyllodes tumors may be confused.
Breast pain (mastalgia) is the most common breast-related complaint among women. Nearly 70% of women experience breast pain at some point in their lives. Fibrocystic change is the most common cause of painful benign breast lumps in women aged 30-50. It affects more than 50% of women at some point in their lives.
Breast pain may occur in one or both breasts or in the axilla. The severity of breast pain varies from woman to woman; approximately 15% of women require treatment. Breast pain is not normally associated with breast cancer.
Breast pain key points:
- It is the most common reason for referral to breast clinics
- It accounts for 50% of all referrals
- Only 7% of patients with breast cancer report breast pain
- It is divided into cyclical and non-cyclical mastalgia
80% of patients with mastalgia require no treatment other than reassurance
Treatment should be considered if:
- Symptoms for more than 6 months
- For >7 days per cycle
- Evening primrose oil (EPO)
- Tamoxifen – effective but not licensed for use in mastalgia
- Diuretics or progestogens are not advised
Cyclical Breast Pain
- Is usually bilateral, and affects the upper outer quadrant
- Is mostly minor and is accepted by many women as ‘part of normal life’
- The average age of onset is 24 years
- There is no consistent hormonal abnormality
- Prolactin levels may be increased
- Essential fatty acid profiles may be abnormal
- There is no evidence of psychopathology
Non-cyclical Breast Pain
- Affects older women
- The average age is 45 years
- It is usually unilateral, often localised
- It is a true non-cyclical mastalgia
- It usually has a musculoskeletal cause
- It is rarely cancer
The most important symptoms and signs of nipple disease are:
- skin changes.
Nipple inversion or retraction may be caused by:
- Duct ectasia
- Underlying carcinoma
- Periductal mastitis – a benign peri-areolar inflammatory condition affecting mainly younger women and often associated with smoking
The causes of nipple discharge are:
- This is common and may be from a single duct or multiple ducts. It may be milky
- Intraductal papilloma
- Duct ectasia
- Peri-ductal mastitis
- This occurs from multiple ducts and is associated with raised serum prolactin levels. It may be due to a pituitary adenoma
Skin changes in and around the nipple are caused by:
- Paget’s disease of the nipple
- Direct invasion by carcinoma (rarely)
Duct ectasia is the dilatation of mammary ducts filled with lipid-rich secretions associated with an inflammatory infiltrate and fibrosis. It may occur as an occult or symptomatic finding.
Duct ectasia (DE) and periductal mastitis (PDM) form a complex of benign breast disorders, including a number of processes that may exist alone or in combination. Some of these conditions are subclinical and represent minor variants of normality (ANDI: aberrations of normal development and involution).
The aetiology of duct ectasia remains obscure. It is most commonly seen in parous than nulliparous women but the exact relationship to pregnancy and lactation is not clear.
However, smoking is a recognised risk factor: women who smoke are three times more likely to develop the condition than those who do not and the incidence appears to be directly proportional to the length of time that the woman has been a smoker. Inflammatory and infective complications are also much commoner and more severe in those who smoke.
Intraduct papilloma is a benign fibro-epithelial tumour arising within a duct. It is a relatively common condition which often presents with unilateral single duct clear or bloodstained nipple discharge.
Mammography is frequently normal. Ultrasound is non-specific but may occasionally detect a nodule within a dilated duct. Ductography may outline a filling defect within the discharging duct.
However, in a patient with nipple discharge, ductography and breast ultrasound are frequently not required as the condition is both treated and diagnosed by surgical micro-dochectomy and so more elaborate imaging does not change the patient management.
As with other papillary lesions, excision, either by surgical micro-dochectomy or ultrasound-guided vacuum assisted biopsy, is necessary in view of the risk of associated malignancy.
Pages Disease of the Nipple
Paget’s disease of the nipple is categorised by the presence of breast cancer cells in the epidermis of the nipple and areola. Clinically, this induces an inflammatory reaction with excoriation of the nipple and areola complex, erythema, moisture and eventually ulceration.
The tumour arises from a sub-areolar duct and extends to the nipple and areola to produce its characteristic findings. Paget’s disease of the nipple is always associated with underlying carcinoma in situ, with or without an invasive focus.
The mammographic findings associated with Paget’s disease of the nipple are similar to those of other breast carcinomas, i.e. mass lesions, microcalcification and distortions. Microcalcification is most commonly seen particularly in the sub-areolar region.
However, mammography is relatively insensitive at detecting the underlying malignancy in Paget’s disease when compared with other breast cancers. Up to 50% of patients may have a normal mammogram.
If there is no clinical or mammographic indication of underlying malignancy and breast conserving surgery is proposed, MRI is useful to exclude the presence of occult malignancy.
The diagnosis of Paget’s disease of the nipple can be confirmed by a cytological smear of the eczematous nipple. Alternatively, a punch biopsy may be performed clinically under local anaesthetic producing a 3-4 mm diameter cylinder of tissue which can provide histological confirmation of the diagnosis.
Rarely, incisional surgical biopsy may be necessary to reach a diagnosis.
Surgical management is by simple mastectomy. If there is an associated invasive carcinoma, the axilla will also need to be staged, either by a sentinel node procedure or node clearance.
Breast inflammation is commonly termed mastitis, and is due to infection. It presents clinically as painful, erythematous and indurated breast. This is distinct from benign fibrocystic change which may cause pain and which is neither infective or inflammatory, but which is sometimes erroneously referred to as chronic mastitis.
Mastitis may progress from a cellulitis to abscess formation. The most common cause is infection secondary to breast-feeding.
Differential diagnosis is inflammatory breast cancer, but the inflammation is usually more localised and there is often leucocytosis and fever.
Both inflammatory breast cancer and bacterial inflammation may show some response to antibiotic treatment.
Ultrasound is the imaging modality of choice. If there is either a diffuse infection, as in infective mastitis, or if an abscess has been partially treated there is no focal collection, but diffuse oedema of the tissues and skin may be seen.
If an abscess is present, there will be a complex hypoechoic collection containing fluid and debris with posterior acoustic enhancement.
Mammography is usually not possible in the acute phase due to pain, but may be indicated post treatment in non-lactating women to rule out underlying malignancy.
Ultrasound is commonly used to guide aspiration of abscesses and monitor response.
Inflammatory Breast Cancer
Inflammatory breast cancer is a rare aggressive type of breast cancer with a median survival of about 25-30 months. It accounts for 1-3% of breast cancer cases.
Clinically it presents as diffuse breast inflammation with a painful swollen breast, erythema, increased warmth, and peau d’orange, and can be confused with benign inflammation which has identical clinical appearances.
A localised mass is not usually evident, and the diagnosis is difficult to make on imaging.
Inflammatory breast cancer is typically due to a diffuse high grade infiltrating ductal carcinoma. There is early invasion of dermal lymphatics, with 80% of patients with inflammatory breast cancer having demonstrable tumour emboli in dermal lymphatic vessels on histology. Most patients have axillary nodal metastases at the time of diagnosis.
Other typical features include:
Vascular dilatation and oedema
No histological features of inflammatory change, i.e. no inflammatory cells seen