Purpose To validate the predictive power for determining breast cancer risk of an automated breast density measurement system with full-fi eld digital mammography (FFDM). Materials and methods Two hundred cancers and 200 controls were imaged with FFDM. Density was measured separately on MLO and CC images using an integral automated volumetric breast density measurement system (Hologic, Quantra). For each cancer, the contralateral mammogram was used. Each cancer was matched to a control case by

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... ate of birth, age at examination and laterality of mammogram used for density determination. Breast density (percentage of fi broglandular tissue) was analyzed by Quantra. Data were analyzed by conditional logistic regression to determine the eff ect on breast cancer risk. Results The percentage of breast density ranged from 6% to 63%. Density declined signifi cantly with age (P <0.001). Overall, there was no signifi cant association of density with risk of breast cancer (P = 0.4). There was a suggestive increase in risk with dense volume higher than 35% (OR = 1.80, 95% CI = 0.96 to 3.39, P = 0.07). There was signifi cant heterogeneity by age in the eff ect of density on risk (P = 0.04). In women aged <50, density was signifi cantly associated with increased risk (P = 0.02), with odds ratios of 6.06, 3.98 and 10.59 for density volumes of 15 to 24%, 25 to 34% and ≥35% respectively, relative to those with <15%. In women aged ≥50 years there was no association of density with risk (P = 0.5). Conclusions Quantra automated volumetric breast density measurement is strongly associated with breast cancer risk in women aged under 50, but not in women aged ≥50 years or over. O2 Ultrasound elastography as an adjuvant to conventional ultrasound in the preoperative assessment of axillary lymph nodes in suspected breast cancer: a pilot study Introduction NICE guidelines recommend conventional ultrasound (CU) of the axilla as preliminary staging in patients with breast cancer. However, up to one-third of nodes showing normal morphology are metastatic on surgical histology [1] . Ultrasound elastography (UE) uses received radiofrequency data to produce an elastogram depicting tissue stiff ness. UE has been researched in the breast but there are no published data regarding UE of the axilla. Methods Fifty women attending the breast unit as symptomatic GP referrals with breast lesions sonographically suspicious of breast cancer underwent UE of the axilla simultaneously with routine CU examination. Elastograms were visually scored, strain measurements calculated and nodal perimeter and area measurements recorded. UE was compared with CU with histology as the reference standard. Results Twenty-nine nodes were histologically normal, 21 were metastatic. Normal nodes were indistinguishable from surrounding tissue on UE. Using cut-off points for biopsy selected for the study, sensitivity was 90% for UE visual scoring, 100% for strain scoring and 76% for CU. Specifi cities were 86%, 48% and 78% respectively. ROC analysis yielded AUC values of 0.9 for UE visual scoring, 0.86 for strain scoring and 0.82 for CU. There was no signifi cant diff erence between any area and perimeter measurements. Conclusions UE can demonstrate axillary lymph nodes and diff erentiate benign from malignant nodes. UE visual scoring shows greatest promise in improving yield without excessive benign biopsies. Reference 1. Britton P, et al.: Use of ultrasound guided axillary node core biopsy in staging of early breast cancer. Eur J Radiol 2009, 19:561-569. O3 Size matters: second breast cancer size following treatment for primary cancer as a predictor of survival Introduction The purpose of surveillance mammography following primary breast cancer treatment is to detect subsequent cancers at the smallest size. We examined the prognostic eff ect of size of ipsilateral breast tumour recurrence (IBTR) and metachronous contralateral breast cancer (MCBC) to assess potential benefi t of surveillance mammography after breast cancer treatment. Methods Second cancers (IBTR n = 1,174, MCBC n = 975) diagnosed between 1 January 1990 and 31 January 2007 from the West Midlands Cancer Intelligence Unit Breast Cancer Registry were analysed. Survival from diagnosis of second cancer was examined using Cox regression models. Risk factors included were prognostic factors of the primary tumour and size of the second tumour. Outcomes were time to all-cause death and to breast cancer death. Estimates are hazard ratios (HRs) and 95% confi dence intervals. Results There were 613 all-cause deaths and 422 breast cancer deaths after IBTR. For both outcomes, second cancers >2 cm had poorer prognosis compared with those <1 cm, HRs were 1.75 (1.29 to 1.37) and 1.99 (1.37 to 2.89). In MCBC there were 358 all-cause deaths, HR 2.14 (1.49 to 3.06), and 23 breast cancer deaths, HR 1.99 (1.38 to 2.83). Conclusions With either IBTR or MCBC the size of the second tumour is important, patients with cancers >2 cm in diameter being at a signifi cantly greater risk of death. Lead-time bias from the mode of detection may be a factor in these results. The frequency of surveillance mammography should be considered for maximum benefi t. O4 Reduced breast biopsy rates with a combined high temporal and high spatial resolution MR imaging protocol at 3 Tesla Purpose To develop a 3.0 Tesla breast imaging protocol that combines high temporal and spatial resolution 3D MR sequences for quantitative time course and morphological analysis of breast lesions. Materials and methods One hundred and sixty-fi ve breast lesions classifi ed by mammography or ultrasound as BIRADS 4 and 5 were included in this prospective IRB-approved study. The MRI protocol consisted of a coronal T2weighted TIRM and a coronal combined high temporal and spatial resolution T1-weighted sequence before and after application of a standard-dose Gd-DOTA (VIBE with a high temporal resolution of SI 1.7 mm isotropic; TA 3.45 min for 17 measurements; FLASH with high spatial resolution of SI 1 mm isotropic; TA 2 min). Lesion size and morphology were assessed according to the BIRADS classifi cation. ROIs for suspicious areas were manually drawn and evaluated for contrast-enhancement behavior by plotting intensity courses against time. Sensitivity and specifi city with a 95% confi dence interval and the negative predictive value (NPV) and positive predictive value (PPV) were calculated. Diagnostic accuracy was assessed. The histopathological diagnoses were used as the standard of reference. Results All malignant breast lesions were identifi ed correctly with a sensitivity of 100%, a specifi city of 84% and a diagnostic accuracy of 95.7%. PPV was 0.94 and a NPV 1. All seven false positive lesions were lesions with atypia. Conclusions The proposed combined 3 Tesla MR imaging protocol, comprising both high temporal and spatial resolution, enabled an accurate detection and assessment of breast lesions with high sensitivity and specifi city reducing false positive breast biopsies O5 MR visible only lesions: what are the predictors for malignant outcome? Introduction To correlate pathological outcomes of MRI vacuum biopsies on MRI visible only breast lesions with lesion morphology, time-enhancement curves and clinical indications to determine the use of these as predictors for malignancy. Methods A retrospective analysis of 277 patients referred for MRI-guided vacuum biopsies of impalpable breast lesions visible only on MRI was performed. All patients had a minimum follow-up period of 11 months. MRI biopsies were undertaken on a 1.5 T magnet using a minimum of 12 passes of vacuum-assisted biopsies. The pathological fi ndings were correlated against BI-RADS appearances and time-enhancement characteristic of the lesions and against the clinical indications for MRI examination. Results A total of 286 vacuum biopsies were undertaken. Eighty-one were malignant (28.3%), of which 72.8% are masses and 27.2% are nonmasses. Only two malignant lesions had a type 1 curve (2.5%), compared with malignant lesions with type 2 (54.3%) and type 3 curves (43.2%). Both malignant lesions with type 1 curve had a suspicious morphology. Nonmalignant lesions with type 3 enhancement included lymph nodes, fi broadenomatoid hyperplasia, papillary lesions, fi brocystic change and lobular neoplasia. Conclusions Lesion morphology and time-enhancement curves are useful predictors of malignancy and can be used to develop an algorithm to help direct appropriate biopsy of MRI-detected lesions. We recommend that in the absence of suspicious morphology, only lesions with type 2 and type 3 curves should be subjected to MRI-guided biopsy. O6 Comparison of fi lm screen, computed radiography and direct digital mammography in the Southern Derby screening programme M Bagnall, AE Turnbull, S Puri Breast Unit, Royal Derby Hospital, Derby, UK Breast Cancer Research 2010, 12(Suppl 3):O6 (doi: 10.1186/bcr2653) POSTER PRESENTATIONS P1 Breast density as a predictor of breast cancer risk Introduction In routine breast screening using 2D digital mammography (2DM), mediolateral-oblique (MLO) and craniocaudal (CC) views are performed to maximise cancer detection. Digital breast tomosynthesis (DBT) improves the visibility of lesions by eliminating the problem of superimposition of normal structures, and there is uncertainty regarding the need for two views. The purpose of this study is to compare the accuracy of two-view 2DM with one-view DBT. Methods Five hundred and one cases were evaluated from the DBT trial dataset of clients recalled for further workup after their initial fi lm-screen mammography. Bilateral two-view 2DM and DBT examination were performed in all study subjects. Mammography scores (1 to 5) based on RCR Breast Group criteria were recorded and an overall score for 2DM was established based on the highest value of MLO and CC scores. Unblinded interpretation of the 2DM followed by MLO-alone DBT was carried out. Statistical analysis was done using the receiver-operative characteristic (ROC). Results There were 111 (22.1%) cancers. The ROC area under the curve (AUC) for two views combined 2DM was 0.915 and for MLO-alone DBT was 0.960 (diff erence 0.045; P = 0.009). The distribution of M-scores against the histology-proven malignant lesions is presented in Table 1 . Conclusions In this series, one-view (MLO-alone) DBT had superior sensitivity compared with two-view 2DM. P4 Accuracy of breast cancer detection with full-fi eld digital mammography and integral computer-aided detection correlated with breast density as assessed by a new automated volumetric breast density measurement system ) Purpose Preoperative breast cancer sizing is required for surgical planning. Breast ultrasound is widely used but may not be accurate. Assisted freehand ultrasound (AFUSON) of the breast is a novel method of ultrasound scanning, combining semi-automated elasticity ultrasound with B-mode imaging. This pilot study investigates whether AFUSON sizing corresponds more closely with wide local excision tumour dimensions than with B-mode alone. Methods Twenty-three patients with early breast cancer were recruited with ethical approval through the NHSBSP. B-mode ultrasound and AFUSON images were acquired in predefi ned planes. Pathology slices were taken in the corresponding longitudinal plane and were digitally scanned. Assessment of tumour dimensions, area and contour were made on B-mode, AFUSON and histopathology scans. The fi ndings were correlated. Results Although there were signifi cant limitations in this pilot study, the tumour dimension accuracy increased from 66% (B-mode alone) to 82% (AFUSON). Tumour area accuracy increased from 61% (B-mode alone) to 90% (AFUSON). Some AFUSON contour images showed a high visual correlation with the equivalent histopathology scans. Conclusions This pilot study suggests that AFUSON may be useful in early breast cancer sizing. Further studies will be done to acquire more data and to address some of the shortfalls in the study. P7 Promoting early symptomatic presentation in older women with breast cancer in the NHS breast screening programme ) Purpose To retrospectively evaluate the sensitivity of computer-aided detection (CAD) for full-fi eld digital mammography (FFDM) in 360 breast cancers with regard to mammographic appearance and histopathological tumor type. Materials and methods Three hundred and sixty breast cancers imaged with FFDM were evaluated retrospectively using CAD. A CAD mark was scored true positive (TP) if it correctly indicated a malignant lesion. All other CAD marks were considered false. Cancer cases were classifi ed as microcalcifi cations (64) , masses (196), or both (100). Histopathological fi ndings were classifi ed as IDC, ILC, DCIS or other. Sensitivity values for CAD according to mammographic appearance and, histopathological fi ndings were analyzed using chi-squared tests. Results A TP mark was observed on 319 out of the 360 cancers (89%). Calcifi cations were signifi cantly (P <0.001) more likely to be marked than masses, 163/164 (99%) compared with 244/296 (82%). The probability of a mass TP mark was signifi cantly related to histological type (P <0.001), with sensitivity being greatest for IDC at 76% (167/221) compared with 67% (38/57) for ILC, 31% (16/51) for DCIS and 74% (23/31) for other types. The probability of a calcifi cation TP mark was also signifi cantly related to histological type, with sensitivity being greatest for DCIS at 75% (38/51), compared with 43% (96/221) for IDC, 33% (19/57) for ILC and 32% (10/31) for other types. Conclusions CAD prompted the signifi cant majority of radiological abnormalities related to cancers and was most accurate for detection of calcifi cation and DCIS, less so for mass lesions and ILC.