Investigation of the breast

Although an accurate history and clinical examination are still the most important methods of detecting breast disease there are a number of investigations which can assist in the diagnosis as follows

Mammography (Fig. 46.2)

Soft tissue X-rays are taken by placing the breast in direct contact with ultrasensitive film and exposing it to low-voltage, high-amperage X-rays. The dose of radiation is approximately 0.1 Gy and therefore mammography is a very safe investigation.

Ultrasound

Ultrasound is particularly useful in young women with dense breasts in whom mammograms are difficult to interpret, and in distinguishing cysts from solid lesions (Figs 46.3 and 46.4). It can also be used to localise impalpable breast lumps.

Magnetic resonance imaging

Magnetic resonance imaging (MRI) is of increasing interest to breast surgeons in a number of settings: it can be useful to distinguish scar from recurrence in women who have had previous breast conservation therapy for cancer (although it is not accurate within 9 months of radiotherapy because of abnormal enhancement); it is the gold standard for imaging the breasts of women with implants; it may prove useful as a screening tool in high-risk women; and it is being evaluated in the management of the axilla in both primary breast cancer and recurrent disease (Fig. 46.5).

Needle biopsy/cytology

Histology can be obtained using a fine needle such as a Trucut or Corecut biopsy device under local anaesthesia (Fig. 46.6). Cytology is obtained using a 21 or 23 Gauge needle and 10-ml syringe with multiple passes throughout the lump without releasing the negative pressure in the syringe. The aspirate is then smeared on to a slide which is air dried (Fig. 46.7). Fine needle aspiration cytology (FNAC) is the least invasive technique of obtaining a cell diagnosis and is very accurate if both operator and cytologist are experienced. However, false negatives do occur, mainly through sampling error, and invasive cancer cannot be distinguished from in situ disease.

Triple assessment

In any patient who presents with a breast lump or other symptoms suspicious of carcinoma, the diagnosis should be made by a combination of clinical assessment, radiological imaging and a tissue sample taken for either cytological or histological analysis (Fig. 46.8): the so-called triple assessment.