women (approximately 7%) present at some time during their lives to their
doctor with a palpable breast cyst. Cysts are most common in the perimenopausal
age group, declining in incidence after the menopause.
possible that cystic disease has a hormonal aetiology. It is very often
bilateral in nature and the relationship to the menopause and response
of cystic disease to endocrine treatment provide indirect evidence that
this is the case. They start usually in the small terminal ducts probably
by excessive secretion and progressive dilatation resulting in microcysts.
The lining cells of the cyst wall secrete fluid, which makes up the fluid
in the cyst. Some studies have suggested that essential fatty acid levels
in the plasma of patients with cysts may be lower than in the general
population. However, the exact aetiology as to the relationship with the
development cysts is unknown.
They develop as result of involution of breast tissue which starts in
the late 20's and and early 30's and may last for over 20 years. Involution
is the process where the tissue between the lobules (stromal tissue) is
replaced by fibrous tissue and the regression of the cells lining the
lobules. Lobules are the basic unit of tissue, which make up breast. When
there is a minor aberration in this normal process it leads to the formation
of microcysts. They result from the kinking or compression of the ducts
by this fibrous tissue or by the active secretion of fluid from the cells.
The enlargement of microcysts leads to the development of macrocysts.
They often do
not cause any symptoms in many women. Patients become aware of breast
lump accidentally. In other cases they can cause pain probably increase
in size or leakage fluid into the surrounding tissues causing secondary
irritation. Even a small increase in volume for unknown reasons has disproportionate
effect in pressure inside the cyst resulting in pain. This explains the
fact that symptoms improve after aspiration of fluid from it. Multiple
cysts are frequently not felt due to the laxity of the cyst and they easily
merge with the surrounding breast tissue. When one or few of the cyst
increase in size they can be so tense they feel hard to feel on occasion
simulating carcinoma. Clinically, may be fluctuate. Occasionally, non-fluctuant
cysts may resemble a carcinoma. Pain can be a presenting symptom and the
history is of short and rapid onset. The total number of palpable breast
cysts varies greatly between individual women, the majority however developing
only a single cyst, 30% having between two and five cysts and the remainder
more than this number.
here to see Management protocol for Breast cysts
All patients over the age of thirty-five years should have a mammogram
prior to aspiration because a small percentage of patients may have an
incidental carcinoma. Fine needle aspiration also has the potential to
distort radiographic images and make interpretation of films difficult.
If the mammogram shows no suspicious abnormality, then cysts may be aspirated
with a wide bore needle to dryness. They are commonly performed under
ultrasound guidance. It can also be performed in the clinic once a diagnosis
is established and the cyst is palpable. There is little value in sending
the fluid to cytology unless it is bloodstained. The clinician must make
sure that there is no mass present following aspiration and, if this is
the case, further assessment will be necessary. In those circumstances
the fluid is sent for microscopic testing and a core biopsy may also be
performed to rule out cancer. It is useful to review the patient six weeks
after aspiration to make sure that there is no re-accumulation and if
so a repeat aspiration may be performed. Repeated accumulation should
be viewed with suspicion and the patient may need excision.
There is a small but
perceptible increased risks of patients with breast cysts developing carcinoma
and debate continues concerning more regular screening of these patients.
It is not the cysts per se pre malignant but the entire breast is said
to be at risk and the cyst being a marker of high risk. However they are
invalidated reports and it is reasonable to conclude that at present there
is no indication for regular follow up of patients with breast cysts.
is ruled out the patients are reassured with all the information about
cysts. If a cyst is aspirated then patient is reassessed again for re
aspiration if it is causing symptoms. They are then discharged with the
advice to come back if new lumps appear. They are also advised to do self-examination
regularly so that they familiarise what is normal for them. They are also
advised to be in the national screening programme if they are in the appropriate
Regular follow up in the breast clinic is usually not done unless the
1. History of breast
cancer in the family.
2. A solitary cyst rather than multiple cysts.
3. Other risks of breast cancer
Patients with multiple
cysts may be helped occasionally with Danazol particularly if there is
mastalgia associated with the cyst formation but the majority of patients
with multiple cysts probably do not need regular treatment or aspiration
unless there are symptoms.
Nodularity in the breasts may be diffuse or focal. Premenstrual nodularity
is so common a clinical finding that it is considered normal and patients
under the age of thirty-five years should be reassured whilst those patients
over the age of thirty-five years should have a mammogram which, if normal,
will provide reassurance for the majority of women. Focal nodularity is
one of the most common presenting symptoms to the breast clinic in women
up to the age of fifty. Most of the changes that occur are part of normal
breast involution and there may be areas of fibrosis or adenosis, cyst formation
or epocrine change, all of which are entirely benign. Only rarely is focal
pathology discovered, for example, sclerosis, epithelial hyperplasia or
cancer. Patients should have an ultrasound of the lesion if they are under
the age of thirty-five and fine needle aspiration cytology should be undertaken
if a discrete lesion is found. For patients over the age of thirty-five,
a mammogram is also essential and fine needle aspiration cytology of the
area should also be taken whether there is a discrete mass or not. If all
the investigations are normal, the patient may be discharged with confidence
but an open appointment for review should be offered.
you require further advice or information please contact the
Macmillan Breast Care Nurses, Hazel Ricard and Hilary Rickwood on 020