Breast Cysts

[buterfly]

After ultrasound, my doctor says that I have a complex cyst and need a biopsy.  What is a complex cyst as opposed to a simple cyst?

[IWantToBeAMom]

From http://www.obgyn.net/displayarticle.asp?page=/bh/articles/newbreasthandoutII

CYSTS
Breast cysts, like cysts elsewhere in the body, can be classified as either simple or complex.

SIMPLE CYSTS
Strict criteria for a simple cyst include:
anechoic center
thin echogenic capsule
enhanced through transmission
thin edge shadows

Cysts which strictly meet these criteria can be classified as simple and have virtually no chance of containing malignancy. They do not need to be aspirated (unless they are causing discomfort or are preventing adequate mammographic compression and evaluation) and they do not need short-interval follow-up. While malignancy inside a simple cyst is virtually unknown, carcinoma can occur in the immediate vicinity of a cyst, so it is necessary to survey the tissues surrounding the cyst as well as the cyst itself.

COMPLEX CYSTS
All cysts that do not meet strict criteria are, by default, classified as complex cysts. However, the term complex breast cyst does not carry the significance of a complex cyst of the kidney or liver. It is important to understand that complex cystic breast malignancies are extremely rare, and usually have other features, which are obviously malignant. The vast majority of complex cysts fall within the broad spectrum of fibrocystic change. For these reasons, the majority of complex breast cysts are not worrisome, and do not need to be aspirated or biopsied.

With the improved resolution of current high-end equipment, a large percentage of breast cysts appear "complex". This is because there is real "stuff" within most breast cysts, due to fibrocystic change. With older equipment these internal cells and debris were not visible, and the cysts appeared simple. Internal contents within breast cysts are part of the spectrum of fibrocystic change and include:

protein globs

cellular debris

cholesterol crystals

foam cells

apocrine cells, floating and papillary

It is necessary, therefore, to have a method of evaluating the relative risk of an individual complex breast cyst for two complicating factors:

infection

malignancy

Categorizing complex cysts into categories can help assess their risk of infection or neoplasm. Complex breast cyst categories include:

diffuse low level internal echoes

fluid-debris levels

septations

eccentric wall thickening