- the most common benign breast lump
- can occur from any age after puberty
- most common in the third decade
- Usually unifocal, but can be multiple.
- Made up of both connective and glandular tissue
- They are usually subject to the same cyclical changes as the other glandular breast tissue – e.g. they may be more tender at a particular time of the month.
- They will grow rapidly in pregnancy as a result of hormonal changes
- Usually well defined borders, but lobulated and lumpy on palpation
- Usually 10-40mm in size, but can be larger
- Mobile – old fashioned nick-name – breast mouse
- They have no potential to become malignant – although sometimes, a constituent part of a breast carcinoma can be a fibroadenoma.
- Due to their rapid growth, they may be confused with phyllodes tumour – a malignant breast neoplasm, accounting for 1% of cases of breast cancer. However, it is rare in young women.
- The most common cause of nipple discharge
- Less common that fibroadenomas
- Tend to occur in middle aged women, but can be seen in younger and older patients
- Usually solitary
- Rise from ductal epithelium
- They are not a form of pre-malignancy
- 80% of patients will have a bloody nipple discharge.
- Most will have a palpable mass. This will typically feel like an elongated mass – along the lumen of a duct. They can also be more spherical in shape, in which case, the duct lumen will be enlarged.
- Usually found within 40mm of the nipple, due to their ductal nature.
- Tubular Adenomas
- 10-40mm diameter, most common in the third decade
- Lactating Adenomas
- These are tubular adenomas which may begin secreting during pregnancy
- Nipple adenomas – a solitary nodule under the nipple, can occur at any age. May ulcerate and be mistaken for Paget’s disease of the nipple, and may cause a bloody discharge. Well defined borders.
- Often cause discomfort
- May result in epithelial hyperplasia – which increases the risk of cancer
- Can cause large palpable lumps, which may cause worry
- Used to be called chronic mastitis – but this is a misnomer, as there is no inflammation involved, and this term should no longer be used.
- Most common in those aged 40-45, but also relatively common in 30-40 year olds
- 10% of women will present with a cyst at some stage
- Post mortem analysis shows that 50% of women have some features of fibrocystic change
- Most common in the 4th and 5th decades of life, and do not tend to occur or persist after the menopause, as they are caused by hormonal effects on ductal and lobular epithelium.
- They may persist after the menopause in those taking HRT
- Most common just before the menopause
- Basically unknown. Hormonal role.
- More common as you approach menopause
- Cyst formation in other organs is usually due to blockage of some sort of duct or lumen, however, this is not the case in fibrocystic change.
- The cysts form as a result of some sort of hormone imbalance, which results in epithelial hyperplasia and duct/lobular dilation, allowing a fluid-filled cavity to form.
- A cysts is essentially a fluid-filled sac in the breast.
- The breast lumps are well circumscribed, and depending on the size, will feel like a grape, or water-balloon in the breast tissue. They are usually firm but not hard, and mobile. The size of the lump may vary with the menstrual cycle, with the lump larger before menstruation, and smaller after menstruation
- Pain – may be cyclical, and is typically worse during:
- The second half of the menstrual cycle
- The lump may be visible on inspection
- Often several may co-exist at once, although there are many cases where only one cyst is present.
- Palpation – described above
- Imaging – usually mammogram, or USS, or both. USS is more sensitive to cystic changes, and the cyst will usually appear dark on the scan. USS is also useful for guided biopsy e.g. in the case of breast implants
- Cytology – FNA – fine needle aspiration. It is relatively easy to take a fluid sample, but you should be wary of sticking a needle in if there is a history of past surgery, particularly breast implant. The fluid is typically brown / green and watery in consistency. It is best practice to send the sample for cytology, particularly if the fluid does not fit this description (e.g. blood, pus). If the fluid appears normal, and there is not a history of cysts, then the likelihood of any significant problem is very low, and the fluid does not need to be tested. Advise the patient to seek further help if any lumps recur.
- The FNA is also often therapeutic, as it removes the fluid, and the lump subsides.
- The fluid volume can be anywhere from a couple of ml, to 60ml. Those less than 5ml will usually not be symptomatic, and in many cases, larger ones may not be a problem.
- Aspirated cysts may recur, in which case, similar treatment can be employed. You should have a higher level of suspicion to send the sample off to the lab in recurrent cases.