Mucocele-Like Lesions in Needle Core Biopsies: Is Excision Always Necessary?
Simone Davion, Kalliopi Siziopikou, Marina Feldman, Ellen B Mendelson, Megan Sullivan. Northwestern University Feinberg School of Medicine, Chicago, IL
Background: When a mucocele-like lesion (MLL) is diagnosed on needle core biopsy (CB), surgical excision is the current standard of care as the spectrum of associated lesions range from benign mucin filled cysts to carcinoma. In this study we examined both the radiologic and pathologic findings in patients with MLL on CB, and correlated them with the excision findings. Our goal was to determine the upgrade rate of MLL at a high volume academic breast center as well as to determine if there is a specific patient population in which close clinical follow-up may be recommended as a treatment option rather than excision.
Design: The pathology information system at Northwestern Memorial Hospital was searched for all MLL diagnosed on CB between 1/1/2003 and 7/30/2010. 44 cases were identified. Pertinent imaging findings (calcifications vs. mass, size of lesion), patient demographic information (age, personal history of breast cancer), and pathologic diagnosis in the excision specimen were recorded.
Results: MLL was diagnosed in 44 of 22,792 CB performed (0.2%) in the time interval included in this study. The 41 patients (some had >1 CB) ranged in age from 27 – 82 years (average = 54). The majority of the biopsies were stereotactic targeting calcifications (42/44; 95%) with two ultrasound guided biopsies for mass lesions (4.5%). 26 CB were diagnosed as MLL (59%), 16 as MLL with atypia (including FEA & ADH; 36%), 1 each as MLL with LCIS and MLL with DCIS (2.3%). No excision pathology was available for 10 patients. The remaining 31 patients underwent surgical excision, 21 of which were benign (68%). Of the remainder, 2 had ADH (3.5%), 6 had DCIS (19%) and 2 had invasive cancer (IC).
The risk of finding a more signifiant lesion at the time of exicision was highly associated with the presence of atypia in CB. No MLL (0/16) were upgraded while 7/14 (50%) of MLL with atypia had either invasive or in-situ carcinoma on excision. One of 2 MLLs associated with masses was upgraded to DCIS (50% upgrade-rate) while 6/29 MLLs that presented as calcifications were upgraded at excision (21% upgrade-rate).
Conclusions: MLLs diagnosed on CB associated with either atypia or a mass lesion had a 50% upgrade rate in our patient population. None of the patients with MLL alone and only calcifications on imaging showed more significant findings on excision and it may be appropriate to offer these patients close clinical follow-up as a treament option.
Monday, February 28, 2011 1:00 PM
Poster Session II # 57, Monday Afternoon