Is it normal breast tissue or something I should be concerned about?

Sometimes it is difficult for GPs to tell what is normal tissue and what is an abnormal breast mass that requires further attention. This is particularly true of premenopausal women, whose normal glandular tissue can feel very nodular, especially in the upper outer quadrant of the breast. There are some important differentiating factors worth remembering, however:

What is the differential diagnosis of a breast lump?

The differential diagnosis of a dominant breast mass includes macrocyst (clinically evident cyst), fibroadenoma, prominent areas of fibrocystic change, fat necrosis and cancer.

What is it most likely to be?

When GPs see women of all different ages presenting with the same symptom (a breast lump) it is essential to remember the changing frequencies of different discrete breast lumps with age (Fig 11.1). Women in their 20s and 30s are much more likely to have a fibroadenoma. Breast

FIGURE 11.1 Changing frequencies of different discrete breast lumps with age

(From Dixon & Mansel,³⁵ with permission from Anthea Carter)

cysts peak at the age of 50 and the incidence of cancer rises slowly before menopause and then more sharply after that, with the largest incidence >60 years.

Conversely, it is worthwhile remembering the differing frequencies of presenting symptoms of breast cancer (Table 11.1).

TABLE 11.1 Relative frequencies of presenting symptoms of breast cancer^*

* Based on the Presentation of Symptomatic Women to the Breast Unit of the Peter MacCallum Cancer Centre, Melbourne, in 2004.

(From NBOCC⁵)

What questions should be asked on history?

When assessing a woman who presents with a breast lump, the GP should take special note of the following factors:

The relevant past history includes:

How should a rigorous clinical breast examination be carried out?

After exposing the chest, the examination commences with inspection under a good light and with the woman in three positions:

Palpation should follow with the patient lying flat, with the ipsilateral arm under her head. Using the flat of the fingers palpate all quadrants of the breast, the axillary tail, and around and behind the nipple. If the breasts are large a pillow can be placed under the shoulder to assist in examining the outer quadrants of the breast. Alternatively, the non-examining hand may be used to immobilise the breast in order to better examine it.

After both breasts have been examined, the patient should sit or stand and the GP should palpate the supraclavicular and axillary fossae for lymph nodes.

When making notes, the GP should record details of any lumps found including size, shape, consistency, mobility, tenderness, fixation and the exact position.

What are the critical issues in the evaluation of a woman with a breast lump?

If a lump is found, the next question is to determine the likelihood of cancer. This can be assessed using the triple test (clinical breast examination, mammography and fine-needle aspiration cytology); a positive triple test is found in 99.6% of breast cancers. Negative results in all components of the triple test provide good evidence that a cancer is unlikely (<1%).⁵ The accuracy of the triple test and each of its components is given in Table 11.2 (p 186).

TABLE 11.2 The accuracy of the triple test and each of its components

The problem with the triple test, however, is the varying degree of sensitivity and specificity of the different components of the test. For example, a clinical breast examination may be more sensitive in the hands of an experienced practitioner. Mammography is less effective in younger women,⁶ in whom ultrasound has a lower false positive rate and is more sensitive.

When should I order an ultrasound and when should I order a mammogram?

In women under the age of 25 and those who are pregnant or lactating, an ultrasound is recommended as the first imaging modality. Mammography is only justified if the clinical findings or the ultrasound results are suspicious of malignancy.

In those 25–35 years, ultrasound is again the preferred imaging modality, although mammography is acceptable if the woman is in the upper range of this age group. It should be used in conjunction with an ultrasound when:

In those over 35, mammography is the preferred imaging modality. Ultrasound should also be used if the lump is consistent with a simple cyst and where the mammogram results are inconsistent with the clinical findings. For this age group GPs can therefore request a mammogram ± ultrasound when they refer the patient for imaging.

When ordering a mammogram is there anything special I need to do?

It is important to note on the referral form that this is not a screening mammography but a diagnostic one. The usual screening study, consisting of two standard views of the breast (craniocaudal and mediolateral oblique), is therefore inappropriate. The radiologist should be notified of the area of clinical concern so that it can be defined with a radiopaque marker to ensure that any noted mammographic abnormalities correspond to the clinical finding. Extra views can then be obtained to ensure that the lesion is adequately visualised.

When do breast cysts occur?

While breast cysts can occur at any age, they are more common in those over 40, accounting for <10% of breast masses in those under 40.⁶

What do they feel like?

Cysts are firm and mobile and may be tender. They fluctuate with the menstrual cycle and tend to occur during periods of hormonal irregularity.

What should a GP do when confronted with an obvious breast cyst?

If an ultrasound or mammogram reveals a simple cyst, the next step is to aspirate the cyst using a fine-bore needle (Fig 11.2). Routine cytologic examination of cyst fluid is not indicated if it appears normal (straw to dark-green colour) and no lump remains,⁵ because of the low likelihood of cancer and the fact that cytologic identification of atypical cells in cyst fluid is not uncommon. This results in the clinical dilemma of a patient whose cyst resolves with aspiration and whose mammogram is normal, but whose cytology report indicates the need for biopsy.⁷

FIGURE 11.2 Breast cyst aspiration: palpable breast cyst steadied and needle passed into the centre

Women should be advised to return for review if the cyst refills; if there is persistent refilling, the patient should be referred to a surgeon.⁵ One follow-up study of 389 women who underwent cyst aspiration found that 44 women had a recurrent cyst and 20 had a solid mass at the aspiration site. In biopsies of the 20 solid masses, two cancers were found.⁸ If there is bloody fluid or a lump remains after aspiration of what appears to be a simple cyst on imaging, the fluid should be sent for cytological testing and the patient referred to a surgeon.

What if non-palpable cysts are found on mammography?

If they are confirmed as simple cysts on ultrasound examination, they require no treatment.

What are fibroadenomas?

Fibroadenomas used to be considered benign tumours of the breast. They are now considered to be aberrations of normal breast development, histologically resembling a hyperplastic breast lobule.⁹ They are also known as the ‘breast mouse’, because they appear to be very mobile.

Fibroadenomas are relatively common, accounting for 12% of all palpable breast masses,¹⁰ 60% of which are in women <20 years.¹¹

Is there a relationship between fibroadenomas and breast cancer?

The general consensus is that having a fibroadenoma does not bring about an increased risk of breast cancer.^10,12

What do fibroadenomas feel like?

They are discrete lumps usually round or oval in shape, firm, rubbery, smooth and very mobile. They range in size from very small to >5 cm. They are usually located in the upper outer quadrant.

While fibroadenomas are often very characteristic, the diagnosis is correct only in half to two-thirds of cases.^13,14 Therefore, a clinical diagnosis is not sufficient to exclude cancer, even in young women, and all women with discrete masses should have a triple test.

How are fibroadenomas managed?

If cancer is excluded using the triple test, the patient has a choice between conservative management or surgical excision. If conservative management is chosen, the limitations of the triple test should be explained to the patient (approximately 1% of cancers can be misdiagnosed), the patient should be followed up on a regular basis, with repeat ultrasonography every 6–12 months, and be reassessed if there is any change.⁹

When should I refer the patient to a surgeon?

Indications for referral are described in Box 11.1. Referrals should be directed towards surgeons with expertise in breast disease.⁵

What is mastalgia?

The clinical name given to painful breasts is mastalgia or mastodynia and it is one of the most common breast complaints that women present with to a general practitioner.

Do all women have painful breasts from time to time?

Mastalgia, like premenstrual symptoms, is suffered by most women at some stage of their lives and is part of a ‘normal’ state of affairs. It is only when the symptoms start to interfere with daily life and persist over a long time that it becomes a ‘disease’ state.