Surgical judgement in assessing the need for cavity shaves during breast conserving surgery

Abstract

Background: The majority of patients with breast cancer in the UK undergo breast conserving surgery (BCS). Breast Conserving Surgery followed by post-operative Radiotherapy has the same 10 year survival rates as mastectomy but a higher incidence of local recurrence. One of the factors associated with local recurrence is tumour cell presence at the specimen resection margin. In order to avoid this some surgeons take extra pieces of tissue from the cavity walls after removal of the main specimen which are known as cavity shaves (CS). However, there is no consensus on adequate radial margin size or the use of cavity shaves. In this study we have analysed the outcomes of patients undergoing Breast Conserving Surgery and the use of cavity shaves in our unit.

Methods: All patients who underwent BCS at our unit over a three year period were included in the study. Data collected from the Pathology report included specimen weight, tumour size, presence of tumour at radial margins and whether cavity shaves had been taken. An assessment was then made on whether the cavity shave correlating to the site of tumour at the radial margin had been taken correctly. The patients’ outcome in terms of further surgery was also assessed.

Results: 323 cases were included in the analysis and of these 138 had one or more CS taken at time of BCS. 88 of these 138 had clear radial margins and 50 had involved radial margins. Surgeons correctly removed the corresponding CS to involved margin in 44.5% of cases.

Conclusions: Breast surgeons are poor at using intra-operative specimen X-rays or palpation of the specimen in assessing whether tumour is present at the radial margin of a breast excision specimen during breast conserving surgery. The use of cavity shaves leads to unnecessary excision of breast tissue.