An audit of mammographic screen detected lesions of uncertain malignant potential (B3) diagnosed on initial image guided needle biopsy: how has our practice changed over 10 years?

AIM: To review all cases of B3 lesion diagnosed at initial image-guided needle biopsy over two 5-year cohorts to identify upgrade rates to malignancy and the effect of changing guidance on the management of such lesions. MATERIALS AND METHODS: Data was collected retrospectively. Mammographic features, biopsy type and management were recorded for each lesion. Upgrade rates for each B3 histological category were quantified. Statistical analysis was performed using SPSS. RESULTS: There were 224 cases in 2005-2010 and 240 cases in 2010-2015. Mammographically 211 lesions were microcalcifications, 182 masses, 65 distortions and six asymmetric densities with no difference in the mammographic features in the two cohorts. Two hundred and eight 14 G core biopsies and 256 initial vacuum-assisted biopsies were performed. There was a statistically significant reduction in benign surgical biopsies and an increase in second-line vacuum biopsy/excision in the latter cohort, with no significant change in the upgrade rate. There was an overall 6% upgrade to invasive malignancy and 13% upgrade to ductal carcinoma in situ (DCIS). The upgrade rates for the following histological categories were atypical intraductal epithelial proliferation (AIDEP) 33.2% (21/63); classical (not pleomorphic) in situ lobular neoplasia (ISLN) 18.2% (6/33); flat epithelial hyperplasia (FEA) 21.7% (20/92); papilloma with atypia 53.8% (7/13), without atypia 12.1% (8/66); and radial scar/complex sclerosing lesion with atypia 16.7% (2/12), and without atypia 7.9% (6/76). CONCLUSION: Upgrade rates remain high for some histological categories even with first-line use of vacuum biopsy. Management of borderline lesions should be considered carefully in a multidisciplinary meeting. In many cases, the need for diagnostic surgical excision has been replaced by image-guided vacuum sampling.

Can digital breast tomosynthesis accurately predict whether circumscribed masses are benign or malignant in a screening population?

AIM: To evaluate whether digital breast tomosynthesis (DBT) can predict if circumscribed masses are benign or malignant by assessing margin sharpness. MATERIALS AND METHODS: Circumscribed masses were evaluated on co-registered two-dimensional digital mammography (2DDM) and DBT. Lesions were categorised as follows: category 1=visible sharp border 0-25% of the total margin; category 2 = 26-50% category 3= 51-75%, and category 4=76-100%. Changes in category between 2DDM and DBT were analysed; if the category was lower on DBT the change was negative, if higher the change was positive. RESULTS: Of 759 lesions, 121 masses classified as circumscribed on DBT were included; 25 were malignant and 96 benign. Of the benign lesions, 8/96 were within category 3 or 4 on 2DDM compared with 48/96 benign lesions within category 3 or 4 on DBT (Fisher's exact test p<0.000527). Forty-eight of 51 (94.1%) lesions categorised as 3 or 4 on DBT were benign and 65/67 (97.01%) of the positive category change group were benign. Lesions in category 1 on DBT had 45.4% chance of being malignant (20/44) compared with 22.72% (20/88) on 2DDM (chi-squared test p<0.001). Sixty-five of 67 (97.01%) lesions in the positive category change group were benign and 23/54 (42.6%) lesions with either no or negative category change were malignant. CONCLUSION: The present study demonstrates 97% accuracy in predicting circumscribed lesions as benign when using positive category change and 94% accuracy when >50% of the margin is sharply defined on DBT.

Role of tomosynthesis in breast imaging going forward.

Digital breast tomosynthesis (DBT) is a modified mammographic technique that overcomes some of the limitations of full-field digital mammography (2DDM) by eliminating the effect of overlapping breast tissue. In the UK, DBT is utilised in both the symptomatic setting and in breast screening assessment clinics. A literature search was conducted from 2010-2017 to ensure that the most recent developments in DBT technology, clinical applications, and assessment of its usefulness in breast screening were reviewed. Technological advances in DBT include the addition of synthetic 2D mammograms, which are generated from the DBT data set, and the use of DBT to guide vacuum-assisted biopsy and excisions. The units from each vendor vary in several aspects, which are detailed in this article. DBT improves diagnostic accuracy and reader confidence when identifying benign and malignant lesions. It has also been shown to be more accurate than 2DDM in assessing tumour size and in the assessment of multifocal tumours. In the screening setting, retrospective reader studies have shown that the addition of DBT to 2DDM showed equivalent or an improvement in sensitivity and specificity when compared to 2DDM alone. Many of these trials showed an increase in invasive cancer detection and a reduction in recall rates. Large prospective randomised controlled trials conducted in Europe and North America will evaluate effectiveness, practicalities, and cost implications of utilising DBT in routine breast screening practice.

The accuracy of digital breast tomosynthesis compared with coned compression magnification mammography in the assessment of abnormalities found on mammography.

AIM: To compare the diagnostic accuracy of the digital breast tomosynthesis (DBT) with coned compression magnification mammography (CCMM). MATERIALS AND METHODS: The study design included two reading sessions completed by seven experienced radiologists. In the first session, all readers read bilateral standard two-view mammograms and a CCMM view of the lesion before giving a combined score for assessment. In the second session, readers read bilateral standard two-view mammograms plus one-view DBT. The two reading sessions of the experiment were separated by at least 2 weeks to reduce the chance of reader memory of the images read in the previous session from influencing the performance in the subsequent session. RESULTS: Three hundred and fifty-four lesions were assessed and receiver-operative characteristic (ROC) analysis was used to evaluate the difference between the two modes. For standard two-view mammography plus CCMM, the area under the curve (AUC) was 0.87 [95% confidence interval (CI): 0.83-0.91] and for standard two-view mammography plus DBT the AUC was 0.93 (95% CI: 0.91-0.95). The difference between the AUCs was 0.06 with p-value of 0.0014. CONCLUSION: Two-view mammography with one-view DBT showed significantly improved accuracy compared to two-view mammography and CCMM in the assessment of mammographic abnormalities. These results show that DBT can be used effectively in the further evaluation of mammographic abnormalities found at screening and in symptomatic diagnostic practice.

Pre-operative factors indicating risk of multiple operations versus a single operation in women undergoing surgery for screen detected breast cancer.

We aim to identify preoperative factors at diagnosis which could predict whether women undergoing wide local excision (WLE) would require further operations. 1593 screen-detected invasive and non-invasive breast cancers were reviewed. Age, presence of ductal carcinoma in situ (DCIS), invasive cancer size on mammography, mammographic sign, tumour type, grade and confidence of the radiologist in malignancy were compared. 83%(1315/1593) of women had a WLE. Of these, 70%(919/1315) had a single operation, and 30%(396/1315) multiple operations. These included repeat WLE to clear margins (60%(238/396)), mastectomy (34%(133/396)) and axillary dissection (6%(25/396)). The presence of mammographic microcalcification, lobular carcinoma and grade 2 malignancy on core biopsy were independent risk factors for multiple operations on multivariate analysis. Women with mammographic DCIS >30 mm were 3.4 times more likely to undergo repeat surgery than those with smaller foci. The multidisciplinary team should pay particular attention to these factors when planning surgery.

Breast screening review--a radiologist's perspective.

Recently published articles in the lay press and scientific journals have questioned the value of breast screening, and have raised concerns about both possible harmful effects and the information provided for females when they receive their screening invitation. A review of data from screening trials and the process for providing information for the public on screening has been announced by Professor Sir Mike Richards, National Clinical Director for Cancer. What are the major issues involved and what expectations should radiologists and other members of the screening team have of the review?

A comparison of the accuracy of film-screen mammography, full-field digital mammography, and digital breast tomosynthesis.

AIM: To measure the change in diagnostic accuracy of conventional film-screen mammography and full-field digital mammography (FFDM) with the addition of digital breast tomosynthesis (DBT) in women recalled for assessment following routine screening. MATERIALS AND METHODS: Ethics approval for the study was granted. Women recalled for assessment following routine screening with screen-film mammography were invited to participate. Participants underwent bilateral, two-view FFDM and two-view DBT. Readers scored each lesion separately for probability of malignancy on screen-film mammography, FFDM, and then DBT. The scores were compared with the presence or absence of malignancy based on the final histopathology outcome. RESULTS: Seven hundred and thirty-eight women participated (93.2% recruitment rate). Following assessment 204 (26.8%) were diagnosed as malignant (147 invasive and 57 in-situ tumours), 286 (37.68%) as benign, and 269 (35.4%) as normal. The diagnostic accuracy was evaluated by using receiving operating characteristic (ROC) and measurement of area under the curve (AUC). The AUC values demonstrated a significant (p = 0.0001) improvement in the diagnostic accuracy with the addition of DBT combined with FFDM and film-screen mammography (AUC = 0.9671) when compared to FFDM plus film-screen mammography (AUC = 0.8949) and film-screen mammography alone (AUC = 0.7882). The effect was significantly greater for soft-tissue lesions [AUC was 0.9905 with the addition of DBT and AUC was 0.9201 for FFDM with film-screen mammography combined (p = 0.0001)] compared to microcalcification [with the addition of DBT (AUC = 0.7920) and for FFDM with film-screen mammography combined (AUC = 0.7843; p = 0.3182)]. CONCLUSION: The addition of DBT increases the accuracy of mammography compared to FFDM and film-screen mammography combined and film-screen mammography alone in the assessment of screen-detected soft-tissue mammographic abnormalities.

Medico-legal issues in breast imaging.

AIM: To identify medico-legal issues that occur in the diagnosis and radiological management of breast disease and to propose measures to reduce the risk of patient complaints and legal action in breast radiology and diagnosis. MATERIALS AND METHODS: Institutional review board approval was not applicable for this study. A retrospective study was undertaken and records of 120 medico-legal investigations over a 10 year period were examined. The reports were compiled by two consultant breast radiologists. RESULTS: The mean age of the patients represented in this study was 48.3 years. The main complaint in this series was a delay in diagnosis (92%) followed by inappropriate or inadequate treatment (8%). 81% of cases were patients who had presented to the symptomatic clinic. The main presenting symptom was a palpable lump (65%). Substandard care was cited in 49/120 cases (41%). The mean average delay in diagnosis was 15.6 months. Of the cases cited as substandard care, 61% were considered the fault of the radiologist and 14% considered the fault of the breast surgeon. Of the cases where the radiologist was considered to be at fault, microcalcification was the most common mammographic sign to be missed or misinterpreted (12/26 cases, 46%). CONCLUSION: The most common complaint in this series was delay in diagnosis with microcalcification being the main mammographic sign that was either not seen or misinterpreted by the radiologist. Clear and precise written protocols are recommended for all breast imaging practice to ensure that medico-legal investigations will be greatly reduced.

Image-guided breast biopsy: state-of-the-art.

Percutaneous image-guided breast biopsy is widely practised to evaluate predominantly non-palpable breast lesions. There has been steady development in percutaneous biopsy techniques. Fine-needle aspiration cytology was the original method of sampling, followed in the early 1990s by large core needle biopsy. The accuracy of both has been improved by ultrasound and stereotactic guidance. Larger bore vacuum-assisted biopsy devices became available in the late 1990s and are now commonplace in most breast units. We review the different types of breast biopsy devices currently available together with various localization techniques used, focusing on their advantages, limitations and current controversial clinical management issues.

The Royal College of Radiologists Breast Group breast imaging classification.

Standardisation of the classification of breast imaging reports will improve communication between the referrer and the radiologist and avoid ambiguity, which may otherwise lead to mismanagement of patients. Following wide consultation, the Royal College of Radiologists Breast Group has produced a scoring system for the classification of breast imaging. This will facilitate audit and the development of nationally agreed standards for the investigation of women with breast disease. This five-point system is as follows: 1, normal; 2, benign findings; 3, indeterminate/probably benign findings; 4, findings suspicious of malignancy; 5, findings highly suspicious of malignancy. It is recommended that this be used in the reporting of all breast imaging examinations in the UK.

Prediction of the presence of invasive disease from the measurement of extent of malignant microcalcification on mammography and ductal carcinoma in situ grade at core biopsy.

AIM: To determine whether the extent of microcalcification and ductal carcinoma in situ (DCIS) grade can be used to accurately predict the presence and size of invasive cancer in cases of malignant microcalcification. MATERIALS AND METHODS: Over a 10-year period, 402 cases of malignant microcalcification from an NHS screening programme were analysed. For each case, measurement of mammographic microcalcification extent, DCIS grade, and the presence and size of invasive carcinoma from the excised surgical specimen were recorded. RESULTS: The final histological diagnosis was DCIS only in 71% (284/402) and DCIS with a focus of invasive disease in 29% (118/402). The risk of invasive disease increased with increasing size of microcalcification from 20% (27/136) for cluster size less than 11mm, to 45% (18/40) for cluster size more than 60mm. The risk of invasive disease also increased with increasing histological grade of DCIS from 13% (4/31) with low-grade DCIS to 36% (86/239) with high-grade DCIS. There were significant associations with the presence of invasive disease for cluster size (p=0.0001) and DCIS grade (p=0.003), and when using univariate analysis with simple [cluster size (p=0.01) and grade (p=0.01)] and multiple [cluster size (p=0.02) and grade (p=0.02)] logistic regression, respectively. The Hosmer-Lemeshow goodness-of-fit test suggests that the multiple logistic regression model has a good fit (p=0.99). CONCLUSION: The multidisciplinary team can use these data in individual cases to estimate the risk of invasive cancer and decide whether to carry out an axillary staging procedure.

The impact of image guided needle biopsy on the outcome of mammographically detected indeterminate microcalcification.

A study was carried out to examine the impact of development in image guided needle biopsy on the outcome of mammographically detected indeterminate microcalcification. Between 01.04.1991 and 31.03.2001, the South East London Breast Screening Programme detected 392 cases of indeterminate microcalcificaton. Histological diagnosis was obtained using open biopsy, fine needle aspiration cytology (FNAC), 18/14 G wide bore needle core biopsy (WBNCB) and 11 G vacuum assisted core biopsy (VACB). The study period group was divided into two. Group A (between 01.04.1991 and 31.03.1996) and group B (between 01.04.1996 and 31.03.2001). There was a significant reduction in the benign open biopsy rate in group B compared to group A (25% vs. 51%) (P=0.0001). Of the malignant cases, there is a higher percentage of ductal carcinoma in situ (DCIS) in group B compared to group A (77% vs. 62%). In conclusion, the implementation of more effective methods of image guided biopsy has led to a 50% reduction in benign open biopsies for indeterminate microcalcification and to an increase in the detection of DCIS.

15. Image-guided breast biopsy.

The introduction of mammographic screening has led to an increased number of impalpable in situ and invasive breast cancers. Image-guided percutaneous biopsy in these patients has advantages over surgical biopsy, primarily cost savings and reducing the number of operations required for definitive treatment. Image-guided breast biopsy is also useful in palpable lesions. Image-guided biopsy should be used in conjunction with full clinical and imaging work-up as part of the triple assessment protocol. Techniques available include fine needle aspiration, automated needle-gun core and vacuum assisted large core biopsy. Lesions visible on ultrasound are preferentially biopsied using ultrasound guidance, while those seen only mammographically are biopsied using stereotactic guidance. Major complications are rare following image-guided biopsy. In most cases further management can be decided based on the biopsy result. If there is discordance between clinical and imaging features and the biopsy result, image-guided percutaneous biopsy should be repeated or surgical biopsy may be required.

Breast cancer screening.

Mammographic screening reduces breast cancer mortality by 24% in women aged > or = 50 years. Women aged 50-53 are invited for their first screen in the National Health Service Breast Screening Programme (NHSBSP), thereafter at three-year intervals until the age of 64. Two-view mammography is offered at the first (prevalent) screening examination and one-view for subsequent (incident) screens. The screening films are sorted into either 'normal' or 'abnormal requiring further assessment'. Assessment is carried out by a specialist multidisciplinary team using the triple approach: clinical examination, imaging and, where appropriate, needle biopsy. Imaging is planned according to the mammographic abnormality--paddle compression view to assess parenchymal distortion, magnification view to assess microcalcification. After confirmation of a suspicious abnormality, needle biopsy is performed. Results of triple assessment are considered together by the multidisciplinary team and further management is planned. There are four likely outcomes: benign/normal, confirmed breast cancer, suspicious but needing diagnostic surgical excision, and diagnostic uncertainty needing early recall for screening.

Multiple 14G stereotactic core biopsies in the diagnosis of mammographically detected stellate lesions of the breast.

AIM: The aim of this retrospective study was to measure the accuracy of stereotactic guided 14 gauge core biopsy in distinguishing between benign and malignant causes of a mammographically detected stellate breast lesion and to assess the impact of the number of core samples taken on the sensitivity for detection of malignancy. MATERIALS AND METHODS: Seventy-two patients with mammographically detected stellate lesions of the breast formed the study group. All patients in the study group underwent multiple 14 gauge core biopsies using prone stereotactic breast biopsy equipment. The diagnostic accuracy of the technique was measured by retrospectively comparing the outcome with the core biopsy results. The result of each core sample was separately recorded to allow analysis of the effect of increasing the number of samples on accuracy. RESULTS: Nine of 72 (12%) did not have surgery. Forty of 72 (56%) had a benign surgical outcome and 23/72 (32%) a malignant surgical outcome [7/72 (10%) non-invasive, 16/72 (22%) invasive carcinoma]. The absolute sensitivity for multiple stereotactic guided core biopsies of stellate lesions for the detection of malignancy was 78% with a complete sensitivity of 100%. The sensitivity for the detection of invasive carcinoma was 94% (15 out of 16 patients). No statistically significant improvement in sensitivity was shown for multiple samples vs one sample, but in two patients, malignant tissue was only found in core samples 6-9, the first five cores showing atypia only. CONCLUSION: Multiple stereotactic guided 14 gauge core biopsies accurately distinguish malignant from benign causes of stellate breast lesions. When core biopsy histology is malignant, therapeutic surgery can be planned. When the core biopsy shows typical features of a benign radial scar, diagnostic surgical excision may not be required to confirm the diagnosis.Kirwan, S. E., (2000). Clinical Radiology55, 763-766.

An investigation into why two-view mammography is better than one-view in breast cancer screening.

AIM: To determine why two-view mammography in screening for breast cancer is more effective than using a single medio-lateral oblique view. MATERIALS AND METHODS: In the United Kingdom Coordinating Committee on Cancer Research randomized trial of one- vs two-view mammography in breast cancer screening the oblique view was assessed by one radiologist and two views (oblique and cranio-caudal) assessed by another. For the present study the mammographic films were retrieved from the screening centres and assessed by three consultant radiologists. Mammographic films were available from 110 women; 87 had their breast cancer detected by both one and two views and in 23 it was missed by one view but detected using two views. Outcome measures were breast size, location and size of the cancer, mammographic features, presence of microcalcification and overall radiological assessment. RESULTS: Although 23 cancers were missed in the original trial when one view was used, only two were not visible on the oblique view. Cancers missed using a single oblique view (and only detected if the cranio-caudal view was available with the oblique) tended to be smaller by about 4 mm (P = 0.05), centrally located in the breast (P = 0.16), not spiculated or round, (P

Stereotactic 14G core biopsy of non-palpable breast cancer: what is the relationship between the number of core samples taken and the sensitivity for detection of malignancy?

AIM: Percutaneous 14-gauge core biopsy (CB) guided by digital stereotactic mammography is now an established technique in the investigation of women with non-palpable suspicious mammographic lesions. Diagnostic sensitivity of CB is affected both by the nature of the mammographic abnormality and by the number of core samples taken. METHODS AND RESULTS: A retrospective review of 500 women who have undergone CB in our institution showed that in 235 cases, invasive or non-invasive carcinoma was found on final surgical histology. Correlation between CB result and surgical histology revealed a significant increase in sensitivity for the diagnosis of malignancy if a larger number of cores were taken (84.3% for two cores and 90.2% for five cores vs. 97.9% for six or more cores). This trend was maintained when patients were subdivided according to mammographic abnormality, either soft tissue mass or microcalcifications. The effect on diagnostic sensitivity of increasing the number of tissue cores obtained was most pronounced in patients with microcalcifications graded as low or moderately suspicious for malignancy (70.1% for two cores and 79.1% for five cores vs 94.0% for six or more cores). The presence of an invasive component in a malignant lesion was correctly diagnosed using CB in 79.2% overall if at least six cores were taken. If the mammographic lesion was a soft tissue mass, this figure rose to 95.7%, but was only 35.7% if the visible lesion was composed of microcalcifications alone. CONCLUSION: Our series confirms the reliability of stereotactic CB in the diagnosis of breast carcinoma. Diagnostic sensitivity is improved by increasing the number of cores taken (to six or more), particularly in women with mammographic microcalcifications of an equivocal nature.

Image-guided breast biopsy: analysis of pain and discomfort related to technique.

A prospective study to evaluate the pain experienced during image-guided core biopsy and fine-needle aspiration (FNA) in a series of 200 woman. There was no significant difference between the pain experienced between core biopsy and FNA. Pain experienced was operator dependent with one of the three radiologists causing significantly more pain than the other two.

Variations in referral pattern for postoperative radiotherapy of patients with screen-detected breast cancer in the south Thames (east) region.

This paper describes the findings of a region-wide audit undertaken in 1995-1996 of post-operative radiotherapy treatment for patients with screen-detected breast cancer. The study covers the first 3 years from the start of the South Thames (East) Breast Screening Programme in June 1988 up to March 1992. The audit shows that only 60% of the patients with invasive carcinoma who were treated by conservation surgery are known to have received radiotherapy. A considerable variation in referral patterns was observed across the region. Analysis suggests that whilst geographical, patient choice and tumour factors may play an important role in the selection of patients for radiotherapy treatment after conservative surgery for early breast cancer, management protocols of surgical units were the most critical factor, and that these appear to vary, depending on the level of involvement of the clinician with the screening programme (as measured by case-load).