Definition: Benign Fluid-Filled Round Mass from the Terminal Duct Lobular Unit (TDLU)
About 25% of Benign Breast Lesions
Risk of Malignancy:
Simple/Complicated: < 1%
Complex: 1-23%
Classification
Simple: Well Circumscribed Anechoic Lesions
BI-RADS 2
Complicated: Homogenous with Low-Level Internal Echoes without Solid Components, Thick Walls, Thick Septa or Vascular Flow
BI-RADS 2-3
Complex: Solid Components, Thick Walls, Thick Septa or Vascular Flow
BI-RADS 4-5
Presentation
Palpable Mass
Pain/Discomfort
Diagnosis
Primary Diagnostic Evaluation: US
Mammogram or MRI Showing Cyst Should Be Followed Up with US
Fine Needle Aspiration (FNA) May Be Considered for Simple/Complicated Cysts
Shows Varying Color (Not Blood)
Collapses with Aspiration
Core Needle Biopsy is Required for Complex Cysts (BI-RADS 4-5)
Treatment
Simple/Complicated Cysts: No Intervention Required
Consider Fine Needle Aspiration (FNA) if Symptomatic, Inflamed or Infected
Follow BI-RADS Recommendations as Appropriate
Complex Cysts: Core Needle Biopsy to Evaluate for Malignancy
Simple Breast Cyst 1
Complicated Breast Cyst 2
Complex Breast Cyst 3
References
Shah G, Jankharia B. Pictorial essay: Breast USG. Indian J Radiol Imaging. 2010 May;20(2):98-104. (License: CC BY-2.0)
Dialani V, James DF, Slanetz PJ. A practical approach to imaging the axilla. Insights Imaging. 2015 Apr;6(2):217-29. (License: CC Not Specified)
Siddiqui B, Faridi SH, Arif SH, Aslam M. Primary hydatid disease of the breast clinically masquerading as a galactocele: A case report. J Transl Int Med. 2015 Apr-Jun;3(2):82-84.(License: CC BY-NC-ND-3.0)