Kenny C. Lai MD, MBA, Presenter: Nothing to Disclose

Thanissara Chansakul, Abstract Co-Author: Nothing to Disclose

Hannah Gilmore MD, Abstract Co-Author: Nothing to Disclose

Shambhavi Venkataraman MD, Abstract Co-Author: Nothing to Disclose

Vandana Mukesh Dialani MD, Abstract Co-Author: Nothing to Disclose

Ferris M. Hall MD, Abstract Co-Author: Nothing to Disclose

Priscilla Jennings Slanetz MD, MPH, Abstract Co-Author: Nothing to Disclose

Fibroadenomas diagnosed by core biopsy are routinely surgically excised if they enlarge on clinical or imaging followup to exclude an associated malignancy.  As malignancy is rarely found, this study was undertaken to determine whether excision of enlarging biopsy-proven fibroadenomas is still warranted.

Review of our institutional pathology database from the 2000 to 2010 identified 1117 cases of fibroadenoma, and retrospective chart review, including review of pathology and imaging findings, was performed.

1117 cases of fibroadenoma were identified in a population of women ranging from ages 17 to 78.  Of these, 378 (33.8%) were diagnosed by ultrasound core needle biopsy. Additionally, 27 cases (2.4%) of lesions presumed to be fibroadenoma on ultrasound were subsequently core biopsied or excised secondary to enlargement on followup imaging.  All 27 (100%) were pathologically proven to be fibroadenoma. Of the 378 cases of core biopsy-proven fibroadenoma, 17 (4.5%) enlarged and were subsequently excised with surgical pathology demonstrating fibroadenoma in all 17 (100%) cases; 201 (53.2%) underwent imaging followup for a mean period of 31.5 months demonstrating no interval enlargement; two (0.5%) underwent imaging followup with enlargement on initial followup, however, were not excised and demonstrated subsequent stability in size for mean followup period of 18 months; 102 (27.0%) were not followed or were lost to followup; and 24 (6.3%) demonstrated qualifying pathologic features (e.g. associated atypia) in addition to fibroadenoma.  Of these 24 cases, 18 underwent excision, three of which demonstrated associated DCIS, six associated LCIS/ALH, five associated ADH, one phyllodes, and three with no atypia on surgical pathology.

The percentage of biopsy-proven, uncomplicated fibroadenomas that enlarge on imaging followup is low. Of such lesions that did enlarge and were excised, none demonstrated malignancy at surgical excision, suggesting excision is not necessary for biopsy-proven, uncomplicated fibroadenomas.

Fibroadenoma is among the most common pathologic diagnoses encountered in breast imaging.  This study addresses the utility of surgical excision for enlarging biopsy-proven fibroadenomas.

Lai, K, Chansakul, T, Gilmore, H, Venkataraman, S, Dialani, V, Hall, F, Slanetz, P, Enlarging Biopsy Proven Fibroadenoma: Is Surgical Excision Necessary?.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034191.html