Excessive Resections in Breast-Conserving Surgery: A Retrospective Multicentre Study

Abstract

The main determinant of cosmetic outcomes following breast-conserving surgery (BCS) for breast cancer is the volume of resection. The importance of achieving optimal oncological control may lead to an unnecessarily large resection of breast tissue. The aim of this study is to evaluate excess resection volume in BCS for cancer by determining a calculated resection ratio (CRR). This retrospective study was conducted in four affiliated institutions and involved 726 consecutive patients with T1-T2 invasive breast cancer treated by BCS between January 2006 and 2009. The pathology reports were reviewed for tumor palpability, tumor size, surgical specimen size, and oncological margin status. The optimal resection volume (ORV) was defined as the spherical tumor volume with an added 1.0 cm margin of healthy breast tissue. The total resection volume (TRV) was defined as the ellipsoid volume of the surgical specimen. CRR was determined by dividing the TRV by the ORV. Of all tumors, 72% (525/726) were palpable, and 28% (201/726) were nonpalpable. The tumor stage was T1 in 492 patients (67.8%) and T2 in 234 patients (32.2%). The median CRR was 2.5 (0.01-42.93). Margin status was positive or focally positive in 153 patients (21.1%). Lower tumor stage was associated with a higher CRR (factor 0.61 [p < 0.0001] and a lower positive margin rate [p = 0.064]). Accordingly, the median CRR of the nonpalpable lesions was higher than that of the palpable lesions (3.1 and 2.2, respectively; p < 0.01), and the involved margin rate was lower (17.4% and 22.5%, respectively; p = 0.13). Of patients with a CRR >4.0, 10.7% still had tumor involved margins. This study clearly shows that BCS is associated with excessive resection of healthy breast tissue while clear margins are not assured. Surgical factors should be modified to improve surgical accuracy.

Optimising surgical accuracy in palpable breast cancer with intra-operative breast ultrasound – Feasibility and surgeons’ learning curve

“…Indeed, in our previous retrospective study, 22.5% of all palpation-guided tumour-excisions presented with tumour-involved surgical margins. [5] Other studies have also reported a high incidence of positive margins after initial excision, ranging from 20 to 60%. [15][16][17] Moreover, it has been shown that many surgeons tend to overexcise volumes of normal tissue in an effort to obtain adequate margins.…”

“…[5,10,12] Still, only one specimen showed surgical margins with DCIS. Therefore, the possible presence of tumour-associated DCIS does not justify excessively large resections to prevent intraductal margin involvement in daily practice, and will therefore not have implications for the use of intra-operative US.…”

“…If the specimen volume is twice the size of the optimal specimen volume, then the CRR would be 2.0. [5,12] Data analysis All data were analysed by using the Statistical Package for the Social Sciences (SPSS statistical software, Version 15.0; SPSS, Inc., Chicago, IL, USA). Scatterplots were generated from time points versus the excision volume and CRR.…”

“…Actually, it was shown that the median excision volume of all palpation-guided tumour excisions is over two times to large. [5] Intra-operative guidance with US may therefore improve surgical accuracy of palpable breast cancer excision as well, being helpful for intra-operative tumour localisation, orientation, direction of planes of excision, and assessment of surgical margins.…”

“…[1,2] The current focus is on improving the surgical accuracy of BCS, which includes a higher rate of margin clearance with smaller excision volume, thereby improving patient satisfaction and cosmetic outcome. [3][4][5][6][7][8] To this end, advances have been made in image-guided breast surgery for nonpalpable breast cancer, and several studies have shown that the use of ultrasonography (US) for intraoperative tumour localisation results in the most accurate surgical excision. [9][10][11][12][13][14] In daily practice, the excision of palpable breast cancer is guided by palpation.…”