A prospective study of tumor and technical factors associated with positive margins in breast-conservation therapy for nonpalpable malignancy.
BACKGROUND
The purpose of this study was to identify factors that predict an increased risk of a positive surgical margin after breast-conserving therapy for nonpalpable carcinoma of the breast.


METHODS
In this prospective study, 305 patients with nonpalpable invasive breast cancer or ductal carcinoma in situ were identified and underwent localization lumpectomy. Patient, technical, and tumor factors with a potential to predict margin status were documented.


RESULTS
A 20% positive margin rate was observed. Univariate analysis of patient, tumor, and technical factors revealed that localizations performed under stereotactic guidance (P < .001), presence of in situ disease, high tumor grade, larger tumor size, multifocal disease, and presence of mammographic microcalcifications (P < .02) were predictive of positive margins. With the exception of tumor grade and mammographic microcalcifications, multivariable analysis identified the same factors.


CONCLUSIONS
This study identified several factors associated with positive margins that should be considered when planning breast-conserving therapy for nonpalpable tumors.
Department of Surgical Oncology, Princess Margaret Hospital, University Health Network, 610 University Ave., Suite 3-130, Toronto, Ontario, Canada M5G 2M9. michael.reedijk@uhn.on.ca
Michael
M
Reedijk
Nicole
N
Hodgson
Gabriela
G
Gohla
Colm
C
Boylan
Charlie H
CH
Goldsmith
Gary
G
Foster
Sylvie D
SD
Cornacchi
David
D
McCready
Peter J
PJ
Lovrics
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology / Q000601:surgery; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology / Q000601:surgery; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D016015:Logistic Models; D008327:Mammography; D015412:Mastectomy, Segmental; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D018365:Neoplasm, Residual / Q000473:pathology* / Q000601:surgery*; D010173:Palpation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors