Intra-operative ultrasound refines breast conserving surgery for palpable breast cancers

Abstract

Background and purpose: Excision of a breast cancer with a tumour-free margin is the principle aim of breast-conserving surgery. Tumour-involved margins of up to 41% are reported with palpation-guided excision. Satisfactory cosmetic outcome is an important secondary aim, with poor cosmesis associated with excision volumes greater than 85cm3. Intra-operative ultrasound (US) has the potential to reduce positive margin rates and tissue volume for palpable breast cancers. The purpose of this study is to report outcomes of a five-year experience in the use of this technique.Methods: A retrospective review was conducted of 176 consecutive patients with a palpable breast cancer, undergoing breast-conserving surgery between 2008-2012. All patients underwent intra-operative US localisation followed by specimen US. Sonography was performed by a breast surgeon or breast sonographer. Specimen volumes were calculated and compared to an optimum specimen volume.Results: Thirty-eight (22%) patients had involved margins on final pathology, with 15 (9%) showing invasive carcinoma, and 23 (13%) having DCIS. The rate of tumour-involved margins was higher for lobular carcinoma (29%) than invasive ductal carcinoma (6%). Of those with positive margins, 93% underwent re-excision, with 40% having residual cancer at resection. Specimen interrogation resulted in 25 patients having additional tissue excised. Two had cancer, and four DCIS, in the marginal tissue. The median value for specimen volume was 60cm3, with 23% of patients having excision volumes greater than 85cm3.Conclusions: Use of intra-operative US localisation coupled with specimen interrogation demonstrated a low rate of positive margins. For the majority of patients, specimen volumes remain lower than those associated with cosmetic dissatisfaction. Intra-operative ultrasound is a useful adjunct to breast conserving surgery. Background and purpose: Excision of a breast cancer with a tumour-free margin is the principle aim of breast-conserving surgery. Tumour-involved margins of up to 41% are reported with palpation-guided excision. Satisfactory cosmetic outcome is an important secondary aim, with poor cosmesis associated with excision volumes greater than 85cm3. Intra-operative ultrasound (US) has the potential to reduce positive margin rates and tissue volume for palpable breast cancers. The purpose of this study is to report outcomes of a five-year experience in the use of this technique. Methods: A retrospective review was conducted of 176 consecutive patients with a palpable breast cancer, undergoing breast-conserving surgery between 2008-2012. All patients underwent intra-operative US localisation followed by specimen US. Sonography was performed by a breast surgeon or breast sonographer. Specimen volumes were calculated and compared to an optimum specimen volume. Results: Thirty-eight (22%) patients had involved margins on final pathology, with 15 (9%) showing invasive carcinoma, and 23 (13%) having DCIS. The rate of tumour-involved margins was higher for lobular carcinoma (29%) than invasive ductal carcinoma (6%). Of those with positive margins, 93% underwent re-excision, with 40% having residual cancer at resection. Specimen interrogation resulted in 25 patients having additional tissue excised. Two had cancer, and four DCIS, in the marginal tissue. The median value for specimen volume was 60cm3, with 23% of patients having excision volumes greater than 85cm3. Conclusions: Use of intra-operative US localisation coupled with specimen interrogation demonstrated a low rate of positive margins. For the majority of patients, specimen volumes remain lower than those associated with cosmetic dissatisfaction. Intra-operative ultrasound is a useful adjunct to breast conserving surgery.