Sonographic-pathologic correlation of complex cystic breast lesions

ObjectiveTo understand the pathologic basis for sonographic features of complex cystic lesions.MethodsFrom 2646 female patients underwent breast sonography at King Chulalongkorn Memorial Hospital from January 2005 through December 2010, 103 cystic lesions were included. Pathologic confirmation was performed by fine-needle aspiration (n=42), core needle biopsy (n=6), excision (n=54) and mastectomy (n=1). Complex cystic breast masses were classified into 3 types as followings; thick outer wall and/or thick internal septa (type I); thick septation and thick wall were defined as equal or more than 0.5 cm, masses containing mixed cystic and solid components (at least 50% of cystic component) (type II), predominantly solid with eccentric cystic foci (at least 50% of solid component) (type III).ResultsIn 103 complex cystic masses, there are 27 lesions (26%) classified as type I cystic breast masses, 37 lesions (36%) as type II cystic breast masses and 39 lesions (38%) type III cystic breast masses, 26 lesions (25.2%) are proved to be malignant. All of type I cystic breast masses in our study are benign, and 14 (38%) of type II cystic breast masses and 12 lesions (31%) of type III cystic breast lesions are proved to be malignant.ConclusionsType II and III lesions should suggest possibility of malignancy and biopsy should be performed in all lesions. All type I lesion in this study are benign. None of other parameters we included in this study (size or margin) can effectively differentiate between benign or malignant cystic breast lesions. Also, grading of the malignant lesions by using type of cystic breast mass cannot be applied.