Manuel A. Torres-Salichs MD,FACS Surgical Oncology, Breast Surgeon

Edileidis Tarrio, ARNP-BC, OCN





Breast Cysts

A breast cyst is a benign, fluid-filled sac. A breast cyst develops when the milk ducts are blocked causing them to dilate and fill with fluid. Breast cysts are the most common cause of benign (non cancerous) breast lumps in women between the age of 30 and 45. They usually disappear after menopause unless the patient is taking hormone replacement therapy. Oral contraceptives may help to regulate the menstrual cycle and reduce the incidence of recurrent breast cysts. Breast cysts vary in size throughout the menstrual cycle. They may cause pain and tenderness.
Breast cysts may be felt on breast exam. They are round or oval, well defined with smooth edges, firm and mobile.
If a mass represents a cyst, it usually represents a benign etiology. A cyst can be aspirated under sonographic guidance if it causes symptoms such as pain and tenderness. Large palpable cysts can also be aspirated. The objective is full drainage of the cyst, with collapse of the cyst wall. Fluid from a cyst is usually discarded except when grossly bloody. The bloody fluid should be examined under the microscope to rule out the possibility of an intracystic carcinoma.


Types of Breast Cysts

Simple Breast Cysts:
They are defined as a fluid filled structure with an imperceptible wall. Unless the patient is symptomatic simple cysts do not required intervention because they do not have malignant potential. Breast sonography is very accurate in making the correct diagnosis of a simple cyst. Simple breast cysts don't require treatment unless they are large and painful. In that case, draining the fluid with a needle (needle aspiration) can ease your symptoms.

This image illustrates a simple cyst. The cyst is well circumscribed and filled with fluid. This is a benign condition and does not require intervention unless it becomes symptomatic.

Complex Breast Cysts:
Complex cysts differ from simple cysts in that they have a solid component or debris within the fluid filled sac. They may also have thin walls or septations. They may contain thick fluid, or fluid that contains dead cells. An aspiration is often recommended to make sure is not solid. Complex breast cysts with an intracystic solid mass have up to 40% incidence of an underlying malignancy. The management of complex breast cysts includes short follow up, needle aspiration or core biopsy and excisional biopsy (complete resection).

This woman had a breast simple cyst presenting as a palpable and painful breast mass. The cyst is being aspirated with a needle under local anesthesia and guidance with a sonogram.