Breast Lumps & Their Investigation

The majority, over 90%, of breast lumps are found to be benign (innocent). If you have found a breast lump, it is essential that you contact a breast specialist for verification. If you have found a breast lump, it is essential that you contact a breast specialist. Many breast lumps that can be felt are not true lumps but localised areas of thickening in the breast - which can occur in a condition called benign mammary dysplasia. The thickening may fluctuate in size during the menstrual cycle - cyclical breast pain (see below) is also a feature of benign mammary dysplasia. Commonly a true lump can either be a cyst, a fibroadenoma or a tumour (cancer). A cyst is a fluid-filled sac & almost always innocent - after aspiration with a small needle they often disappear, not to fill again. A fibroadenoma is a solid lump - well rounded & moves easily, slipping from the examining hand - sometime referred to as a "breast mouse". Again, like a cyst, it is almost always benign (i.e. non-cancerous) Sometimes fibroadenomas regress & can disappear but often they persist & may get larger, especially during pregnancy' when they can become very large & painful. For these reasons you may be advised to have it removed - this is a small operation & can be carried out under local anaesthesia if you wished. The incisions are placed for the best cosmetic effect & often are not visible. A newer method of treatment - still under trial - is to insert a laser into the fibroadenoma & "burn" it with a laser. Cancer can present as a solid lump & that is why any breast thickening or lump must be investigated thoroughly. Clinical examination is a very good indication of its nature, but tests are also necessary to complete the assessment.

These tests are as follows:

1.      Mammography - This is by far the best single test we have today to examine the breast as a whole.   The downside is that it involves exposing the breast to a small amount of radiation, which is particularly detrimental to young breasts.  After the age of 40 or so its effects are far less important & can be regarded as negligible when mammography is carried out at yearly intervals.   In the future a harmless scan (called MRI  -  magnetic resonance imaging) may replace mammography.

2.      Ultrasound scan - This is completely harmless & can be carried out as frequently as necessary. It is used as an addition to mammography. Unlike mammography it can distinguish between a solid lump (which could be significant) & a fluid-filled lump – a cyst – (which is almost always innocent).   It is particularly useful to assess the young “dense” breasts; whereas mammography is more informative in the older “fatty” breast.

3.      “Needling” the lump - Inserting a small needle into a solid breast lump & applying suction on the syringe draws up thousands of cells which are then transferred onto a glass slide for microscopic examination, i.e. cytology.   This gives us very useful information as to the nature of the lump.   If the lump is a cyst, the fluid is aspirated & the lump normally disappears.   The fluid is then examined under the microscope to confirm that all is well.   Inserting a thin needle does not need local anaesthesia & usually causes no or only a slight discomfort.    Sometimes we need to have a small piece of the solid lump for more thorough microscopic examination, i.e. histology .  In this case local anaesthesia is injected before inserting a larger needle to remove a cylindrical core of the lump.  

A combination of clinical examination, mammography, ultrasound scanning & needling for cytology or histology can tell us whether the lump is innocent (benign) or a cancer (malignant).

The management of breast cancer is covered in a separate section.