ABSTRACTS 7 patients testing positive had no involvement histologically, (1 follicular lymphoma, 1 granulomatous disease and 5 sampling errors). The average time for the test was 55 minutes. Conclusion: Gene expression analysis on sentinel lymph nodes usually allows the surgeon to decide whether to clear the axilla immediately with a high degree of accuracy. More time needs to be allowed on operating schedules but in this series of 100 patients it saved 20 patients from second procedures. P8. Efficacy of intra-operative wire localisation of breast lesions using ultrasound Gargeshwari Krishnamurthy Guru Raghavendra, V. White, J. Harvey, M. Youssef, W. Wotherspoon, M. Carr Wansbeck General Hospital, Woodhorne Lane, Ashington, NE63 9JJ Introduction: Ultrasound is commonly used for pre-operative wire localisation of breast lesions and involves an uncomfortable procedure for patients. Intra-operative localisation has the potential to decrease patient discomfort and avoid wire displacement. This study aimed to assess the efficacy of intra-operative wire placement by a breast radiologist. Methods: From January 2007 to July 2008 all patients suitable for ultrasound guided wire localisation were offered intra-operative placement. After induction of anaesthetic, localisation was performed by one consultant radiologist. Satisfactory excision was confirmed by immediate ultrasound or radiography. Data was collected retrospectively and compared to a patient cohort undergoing pre-operative localisation between 2005-2007 using the chi-square test. Results: All patients offered intra-operative localisation during the study period chose this over pre-operative localisation. 32 patients underwent localisation, 10 for diagnostic procedures and 22 to perform wide local excision of a malignancy. 100% of lesions were successfully localised. Re-excision was required following 10/22 wide local excisions which is not significantly different to pre-operative localisation in our series. No wires were displaced between localisation and surgery. Conclusions: Intra-operative localisation avoids patients undergoing two procedures and is preferred by patients. The technique allows the radiologist to place the wire on an anaesthetised patient and gives the surgical team insight into the path and depth of the wire, thus facilitating their dissection. The procedure is efficacious and comparable to pre-operative localisation. Intra-operative localisation is a safe and advantageous procedure to the patient and surgical team but does require a dedicated radiological team. P9. Intraoperative sentinel lymph node assessment - does it reduce the need for a second operation? Julia Henderson, J. Ooi, J. Winstanley Royal Bolton Hospital, Minerva Rd, Farnworth, Bolton, BL4 0JR Introduction: ISLNA is proposed as a method of avoiding a second operation in patients with a positive sentinel lymph node biopsy (SLNB). However some patients may need further surgery if the primary cancer is incompletely excised or occult disease subsequently identified. This study was conducted to determine how many patients would benefit from ISLNA by avoiding a second operation. Methods: All patients who underwent SLNB with wide local excision (WLE) or mastectomy and returned for ANC at RBH between 01/01/2007 and 31/12/2009 were included. Patients were identified from operating diaries and theatre records. Results: 57 patients required ANC following a positive SLNB. 37 had WLE and 19 mastectomy. 35% (n¼13) of patients who had WLE underwent a second breast procedure at the time of their ANC. 2 had re-excision of margins and 11 mastectomies. Conclusions: ISLNA offers benefit to patients having a mastectomy in avoiding a second operation. Patients with axillary disease that is not apparent on imaging at diagnosis may have more extensive occult breast
1109 disease than initially anticipated. This was reflected in the high proportion of patients undergoing WLE followed by a second breast procedure. Over a third of patients having WLE would not have avoided a second procedure. A pilot scheme should be targeted at patients undergoing mastectomy as a primary breast procedure as they have the most to gain. P10. Outcomes for symptomatic women with mammographically indeterminate breast lesions at a single centre Ruth James, D. Bapu, H. Coxall, F. Charlton, K. Hasan, G. Cunnick Wycombe Hospital, Queen Alexandra Rd, High Wycombe, Bucks, HP11 2TT Background: Few studies have looked at the significance of M3 (mammographically indeterminate) lesions in symptomatic populations. Material and methods: All M3 lesions in symptomatic women reported over a 2 year period at a single centre were reviewed. Computerised systems were used to identify whether further imaging, cytology/histology or surgery had subsequently been performed. Results of investigations were recorded. Results: 301 M3 reports were identified (7% of all mammograms performed). Results were available for 299. 143 women had a malignancy excluded through further imaging (repeat mammograms, compression views or ultrasound). 156 women underwent fine needle aspiration and/or core or excision biopsy. A total of 10 patients underwent excision biopsy. 44 women were found to have a malignancy (14.6%). Conclusion: Indeterminate mammographic results lead to considerable psychological morbidity. Women require evidenced information regarding potential outcomes following an M3 report. The positive predictive value for malignancy of an M3 lesion in our symptomatic population was 14.6%. P11. The use of cavity biopsies makes the assessment of margins safer after breast conserving surgery. Elizabeth Squire, J. Male, R. Kirby University Hospital of North Staffordshire, Breast Department, City General, Newcastle Road, Stoke-on-Trent, ST4 6QG Introduction: Resection margin status after breast conserving surgery affects local recurrence rates. Cavity biopsy (CB) assessment after wide local excision (WLE) may increase the accuracy of asssessing tumour clearance. Methods: This audit examined tumour, CB and margin status of WLE specimens over an 18 year period to determine whether routine collections of CBs continue to be of beneficial practice. Data was collected prospectively from 1991-2009, from a total of 826 WLE carried out by one consultant. Sixty-nine cases were excluded due to insufficient data or no CB being performed. Patients were categorised into four subgroups depending on a positive or negative margin and CB status. Data was further categorised into DCIS and invasive carcinoma. Results: 83% were found to be margin and CB negative. The three remaining categories: margin and CB positive, margin positive-CB negative and margin negative-CB positive, showed similar proportions with 5.45%, 7% and 6.36% of cases respectively. The latter group are those normally thought to be clear. Marginal involvement decreased with increasing tumour grade (14.2%, 13.24%, 10.55%) whereas cavity involvement increased (9.88%, 12.20%, 13.07%); this finding was independent of margin depth. CB involvement with a negative margin was found to increase across tumour grade. (p¼0.0081) Conclusions: The significant number of cases with cavity involvement in the absence of margin involvement (>6%) suggests that performing cavity biopsies remains good practice and is superior to using margin status alone to assess completeness of excision following breast conserving surgery.