Role of early post-operative breast MRI: how helpful is it in deciding the next step for women who may have residual disease?

OBJECTIVES: Positive resection margins following breast conserving surgery are a risk factor for local disease recurrence. Subsequent management of patients is often not straightforward, with post-operative breast MRI increasingly used to aid decision-making. Interpretation of MRI after surgery can prove challenging due to local inflammatory enhancement. We reviewed our experience of post-operative breast MRIs to determine their ability to detect residual disease and to evaluate how they changed initial patient management from re-excision to an alternative. METHODS: A search of breast MRIs performed from August 2014 to December 2019 was undertaken, to identify those performed post-operatively within 4 months of breast conserving surgery. Electronic patient records and imaging were evaluated to determine additional work-up, pathology and surgical outcomes. RESULTS: Of the 2274 breast MRIs during the study period, 44 (2%) were performed post-operatively to evaluate 47 breasts. MRI was normal in 20 cases (43%), suspicious findings at surgical cavity only in 13 (28%), suspicious ipsilateral distant breast findings only in 6 (13%), and both cavity and distant findings in 7 cases (15%). Contralateral abnormalities were identified in 3 cases. Following MRI, mastectomy was performed in 11 cases, re-excision in 25, with 2 subsequent mastectomies, and multidisciplinary team accepted margins in 11 cases, 10 of whom underwent post-operative radiotherapy. MRI altered initial patient management from re-excision to an alternative in 25 cases (45%). CONCLUSION: Post-operative breast MRI, although potentially challenging to interpret, can prove useful in planning the next step in patient management, particularly in its ability to evaluate the whole breast. ADVANCES IN KNOWLEDGE: Post-operative breast MRI is increasingly requested at multidisciplinary team following breast conserving surgery with positive surgical margins on histology, however interpretation is challenging. The value of these studies lie in assessment of the distant breast rather than the surgical resection cavity and can alter patient management guiding the most appropriate next step for definitive treatment.

The effect of false positive breast screening examinations on subsequent attendance: retrospective cohort study.

OBJECTIVES: To investigate the effect of false positive breast screening examination results on subsequent attendance in the UK National Health Service Breast Screening Programme. METHODS: 253,017 previously screened women who were invited for rescreening were studied. Attendance rates of women who had received a normal result at the last (index) screen were compared with those of women who had received a false positive result. The effects of age, type of index screening examination (prevalent or incident) and tissue sampling at assessment were investigated. RESULTS: Women who had a false positive prevalent index screening examination were significantly more likely to reattend than those who had a normal prevalent index screening examination (87.7% vs. 86.0%). There was no significant difference in reattendance rates between women who had a false positive incident index screening examination and those with a normal incident index screening examination. However, women who underwent needle sampling or open biopsy following false positive incident index screening examinations were 12% and 60% less likely to reattend, respectively, than women whose index screening examinations were normal (p < 0.001), although there was variation between centres. Increasing age significantly reduced the likelihood of reattendance. The overall reattendance of women who had been screened only once was six percentage points lower than that of women who had been screened more than once. CONCLUSIONS: The findings suggest that most women who undergo the breast screening assessment process retain confidence in breast screening. Needle sampling and open biopsy should be used judiciously in the assessment of screen-detected abnormalities in view of the reduced reattendance that results from their use after incident screening examinations.

Interdisciplinary consensus on the uses and technique of MR-guided vacuum-assisted breast biopsy (VAB): results of a European consensus meeting.

PURPOSE: Quality assurance of MR-guided vacuum-assisted breast biopsy (VAB). METHOD: A consensus was achieved based on the existing literature and experience of an interdisciplinary group comprising European specialists in breast imaging and VAB. RESULTS: Full imaging work-up must be completed according to existing standards before an indication for MR-guided VAB is established. The procedure should be reserved for lesions demonstrable by MRI alone. Acquisition of >24 cores (11-Gauge) should be routinely attempted, with the intention of sufficiently removing small lesions for accurate diagnosis. Following biopsy the patient should be re-imaged to demonstrate the biopsy site and its proximity to the lesion and hence the likely accuracy of the sampling. All patients should be discussed in a regular interdisciplinary conference and a documented consensus reached regarding patient management. Regular audit and review of all MR-guided VAB results and subsequent follow-up are recommended. CONCLUSION: This consensus includes protocols for the indication, performance parameters, interdisciplinary interpretation therapeutic recommendation, documentation and follow-up of MR-guided VAB. It does not replace official recommendations for percutaneous biopsy.

Breast cancers: noninvasive method of preoperative localization with three-dimensional US and surface contour mapping.

Formal ethical approval was granted by the local research ethics committee; all participants gave written consent. The purpose of the study was to prospectively evaluate the feasibility of a noninvasive method of breast tumor localization in 25 participants, based on the coregistration of three-dimensional (3D) ultrasonographic (US) data with surface contour data obtained by using a 3D laser camera. The tumor is segmented from the US data, and a surface-rendered 3D image of the tumor, in relation to the breast surface contour, is produced. From a personal computer in the operating room, the surgeon can dynamically view a 3D image of the tumor within the breast. This noninvasive method was equivalent to conventional techniques in 18 of 25 patients but was less successful in larger-breasted patients. In selected patients, this localization method could provide an alternative to conventional invasive techniques and can offer both spatial localization and tumor morphology.

High definition three-dimensional ultrasound to localise the tumour bed: a breast radiotherapy planning study.

BACKGROUND AND PURPOSE: Complex radiation techniques, such as conformal radiotherapy for partial breast irradiation, require accurate localisation of the tumour bed. This study investigated high definition 3D ultrasound for breast tumour bed localisation. Study aims were: firstly, to determine how easily a tumour cavity could be visualised with 3D ultrasound; secondly, to determine the accuracy of computed tomography (CT) and 3D ultrasound co-registration; thirdly, to compare 3D ultrasound with other methods of localisation. MATERIALS AND METHODS: 3D ultrasound examinations were carried out in 40 women attending for breast radiotherapy. 3D position data were co-registered with the radiotherapy planning CT. 2D ultrasound and CT, surgical clips and CT, and CT alone were also used to localise the tumour bed in 32/40, 14/40 and 5/40 patients, respectively. Tumour bed volume and centre of gravity measurements for all methods of localisation were compared. RESULTS: Mean surgery to imaging interval was 44 days (range 23-86 days). The post-operative cavity was seen in all cases using the 3D ultrasound, and was graded as highly visible, visible and subtle in 21/40 (53%), 12/40 (30%) and 7/40 (17%) cases, respectively. There was a statistically significant improvement in the ability of 3D ultrasound to localise the tumour bed compared with 2D ultrasound. CT-ultrasound registration was achieved in all cases. Two-dimensional and 3D ultrasound showed smaller tumour bed volumes than clips. CONCLUSIONS: Three-dimensional ultrasound localisation of the tumour bed appears superior to 2D ultrasound. It can also be co-registered with a planning CT, thus allowing additional information on the size and location of the tumour bed to be integrated into complex radiotherapy planning.

A test of performance of breast MRI interpretation in a multicentre screening study.

OBJECTIVES: The aim of this study was to assess the consistency and performance of radiologists interpreting breast magnetic resonance imaging (MRI) examinations. MATERIALS AND METHODS: Two test sets of eight cases comprising cancers, benign disease, technical problems and parenchymal enhancement were prepared from two manufacturers' equipment (X and Y) and reported by 15 radiologists using the recording form and scoring system of the UK MRI breast screening study [(MAgnetic Resonance Imaging in Breast Screening (MARIBS)]. Variations in assessments of morphology, kinetic scores and diagnosis were measured by assessing intraobserver and interobserver variability and agreement. The sensitivity and specificity of reporting performances was determined using receiver operating characteristic (ROC) curve analysis. RESULTS: Intraobserver variation was seen in 13 (27.7%) of 47 of the radiologists' conclusions (four technical and seven pathological differences). Substantial interobserver variation was observed in the scores recorded for morphology, pattern of enhancement, quantification of enhancement and washout pattern. The overall sensitivity of breast MRI was high [88.6%, 95% confidence interval (CI) 77.4-94.7%], combined with a specificity of 69.2% (95% CI 60.5-76.7%). The sensitivities were similar for the two test sets (P=.3), but the specificity was significantly higher for the Manufacturer X dataset (P<.001). ROC curve analysis gave an area under the curve of 0.85 (95% CI 0.79-0.92) CONCLUSIONS: Substantial variation in all elements of the scoring system and in the overall diagnostic conclusions was observed between radiologists participating in MARIBS. High overall sensitivity was achieved with moderate specificity. Manufacturer-related differences in specificities possibly occurred because the numerical thresholds set for the scoring system were not optimised for both equipment manufacturers. Scoring systems developed on one equipment software may not be transferable to other manufacturers.