Lumpectomy specimen margins are not reliable in predicting residual disease in breast conserving surgery

BACKGROUND

In breast conserving surgery, the concordance between lumpectomy margin (LM) status and the status of the corresponding lumpectomy cavity remains uncertain.

METHODS

We analyzed pathology reports of lumpectomies from 2004 to 2006. We included those which contained both ink-directed LM and complete (≥4) separate corresponding shaved cavity margins (SCMs). SCM pathology was used as a surrogate for lumpectomy cavity status, to determine the predictive value of LM for residual disease.

RESULTS

Pathology from 1,201 pairs of LM and SCM from 242 patients was compared. LM status predicted corresponding lumpectomy cavity status with 50.9% sensitivity, 69.5% specificity, 35% positive predictive value, and 81.4% negative predictive value, giving an overall accuracy of 64.9%.

CONCLUSIONS

Oriented LMs are not reliable for predicting lumpectomy cavity status, and therefore not reliable for directing re-excision. Taking complete, oriented SCMs at the time of lumpectomy may improve accuracy compared with traditional LM assessment.

Is intraoperative frozen section analysis of reexcision specimens of value in preventing reoperation in breast-conserving therapy?

OBJECTIVES

A prior study at our institution showed a marked reduction in reoperation for margin reexcision following the development of an intraoperative frozen section evaluation of margins (FSM) practice on lumpectomy specimens from patients undergoing breast-conserving therapy (BCT). This study aimed to examine the frequency of FSM utilization, FSM pathology performance, and outcomes for BCT patients undergoing margin reexcision only.

METHODS

Consecutive reexcision-only specimens were reviewed from a 40-month period following the development of the FSM practice. Clinicopathologic features and patient outcomes were assessed.

RESULTS

FSM was performed in 46 (30.7%) of 150 reexcision-only operations. Of the 46 operations with FSM, there were 28 (60.9%) true-negative, 12 (26.1%) true-positive, six (13.0%) false-negative, and no false-positive cases. There was no difference in further reexcision, total operations, or conversion to mastectomy among patients with and without FSM. Need for further reexcision was significantly associated with tumor multifocality (P = .008).

CONCLUSIONS

Despite overall good pathology performance for FSM in reexcision-only specimens, use of FSM did not affect patient outcome. Rather, underlying disease biology appeared most significant in predicting whether adequate surgical margins could be attained.