Underestimation of DCIS at MRI-guided vacuum-assisted breast biopsy.
OBJECTIVE
The study objective was to assess the rate of underestimation of ductal carcinoma in situ (DCIS) at MRI-guided 9-gauge vacuum-assisted breast biopsy.


METHODS
An institutional review board-approved retrospective review was performed of 373 consecutive lesions that had undergone MRI vacuum-assisted breast biopsy. In 34 lesions with subsequent surgery, vacuum-assisted breast biopsy yielded DCIS without frank microinvasion or invasion. DCIS underestimates were lesions for which vacuum-assisted breast biopsy yielded DCIS without frank microinvasion or invasion at biopsy and surgery yielded invasive cancer. Records and pathology findings were reviewed.


RESULTS
Among 34 lesions, vacuum-assisted breast biopsy histology was DCIS in 29 and DCIS with possible microinvasion in five. Of 29 lesions yielding DCIS at MRI vacuum-assisted breast biopsy, surgical excision revealed invasive cancer in five (17%; 95% CI, 6-36%). The DCIS underestimation rate was significantly higher in lesions 6 cm or larger versus smaller lesions (60% vs 8%, p = 0.02). MRI lesion type, kinetics, number of specimens, menopausal status, and target sampling versus excision did not significantly affect underestimation. Of five lesions yielding DCIS with possible microinvasion at MRI vacuum-assisted breast biopsy, surgery revealed invasive carcinoma in four (80%; 95% CI, 28-99%). DCIS underestimation was significantly more likely if MRI vacuum-assisted breast biopsy showed possible microinvasion than if it did not (80% vs 17%, p =0.01).


CONCLUSIONS
Underestimation occurred in 17% of lesions yielding DCIS and in 80% of lesions yielding DCIS with possible microinvasion at MRI vacuum-assisted breast biopsy. DCIS underestimation was significantly more likely in lesions measuring 6 cm or larger. No other patient or lesion factors significantly affected DCIS underestimation at MRI vacuum-assisted breast biopsy.
Lee
Jung-min
JM
Breast Imaging Section, Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Ave., New York, NY 10021, USA.
Kaplan
Jennifer B
JB
Murray
Melissa P
MP
Mazur-Grbec
Marzena
M
Tadic
Tade
T
Stimac
Damir
D
Liberman
Laura
L
D000328:Adult; D000368:Aged; D001706:Biopsy / Q000295:instrumentation*; D001943:Breast Neoplasms / Q000473:pathology*; D002278:Carcinoma in Situ / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology*; D016009:Chi-Square Distribution; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D053783:Magnetic Resonance Imaging, Interventional; D008875:Middle Aged; D012189:Retrospective Studies; D014618:Vacuum