Can high-frequency ultrasound predict metastatic lymph nodes in patients with invasive breast cancer?

Aim To determine whether high-frequency ultrasound can predict the presence of metastatic axillary lymph nodes, with a high specificity and positive predictive value, in patients with invasive breast cancer. The clinical aim is to identify patients with axillary disease requiring surgery who would not normally, on clinical grounds, have an axillary dissection, so potentially improving outcome and survival rates. Materials and methods The ipsilateral and contralateral axillae of 42 consecutive patients with invasive breast cancer were scanned prior to treatment using a B-mode frequency of 13 MHz and a Power Doppler frequency of 7 MHz. The presence or absence of an echogenic centre for each lymph node detected was recorded, and measurements were also taken to determine the L/S ratio and the widest and narrowest part of the cortex. Power Doppler was also used to determine vascularity. The contralateral axilla was used as a control for each patient. Results In this study of patients with invasive breast cancer, ipsilateral lymph nodes with a cortical bulge ≥3 mm and/or at least two lymph nodes with absent echogenic centres indicated the presence of metastatic axillary lymph nodes (10 patients). The sensitivity and specificity were 52.6% and 100%, respectively, positive and negative predictive values were 100% and 71.9%, respectively, the P value was 0.001 and the Kappa score was 0.55.\ud Conclusion This would indicate that high-frequency ultrasound can be used to accurately predict metastatic lymph nodes in a proportion of patients with invasive breast cancer, which may alter patient management

First steps in optimizing breast screening in Mongolia: Understanding radiologists’ performance in reading mammograms and mammographic breast density

Advanced diagnoses of breast cancer have become a serious public health issue in Mongolia. Whilst mammography has been proven to be an effective screening approach for breast cancer and well established amongst developed countries, such program has not been introduced in Mongolia. In addition in Mongolia, a lack of research around breast cancer continues to exist. The purpose of this thesis is to understand mammographic diagnostic accuracy and mammographic breast density (MD) in Mongolia, both of which are important considerations, which will inform a future national screening program. To address this aim, three studies were conducted; the first two were radiologists’ performance studies in reading mammograms with different levels of difficulty. The mammographic detection of Mongolian radiologists (case sensitivity of 63% and lesion sensitivity of 34%) was substantially lower compared with that of Australian radiologists. The third study investigated the MD features of 1985 Mongolian women using the Breast Imaging Reporting and Data system (BI-RADS) density categories. The majority of women (58%) were found to have low-density categories (category A and B) and significant associations were observed between MD; age (OR = 6.8, 95% CI: 5.5, 8.0), weight (OR = 4.5, 95% CI: 3.4, 6.0) and BMI (OR=13.2, 95% CI: 8.6, 20.0). Findings from this research have demonstrated that mammographic diagnostic accuracy is sub-optimal in Mongolia. Moreover, images with different levels of difficulty did not alter the reading performance of Mongolian radiologists suggesting the need for improving breast cancer detection skills urgently. The output of this work also demonstrated that low density was predominant in Mongolia. The results will impact on health policy around screening in Mongolia. They will inform educational strategies that are needed to transform diagnostic efficacy and will provide a good basis for decision making around screening modality choices

Digital Breast Tomosynthesis: Outcomes and Tumor Characteristics in Women Recalled From Screening

Breast cancer is the most frequently diagnosed and second leading cause of cancer deaths in women, accounting for 25% of cancer diagnoses and 15.4% of cancer deaths in developed countries. Thus, early detection of breast cancer through screening has become increasingly important in mortality reduction efforts. Yet, mammography has faced considerable controversy in balancing the benefits and harms associated with screening. Digital breast tomosynthesis has emerged as an important imaging technique which, compared to standard mammography alone, reduces recall rates and false positives, and improves cancer detection. Additional cancers detected with tomosynthesis have been poorly characterized in the literature to date. To assess the effectiveness of screening with adjunct tomosynthesis, we propose to utilize our large database to characterize cancers detected in true positive recalls. Our findings will help clinicians make well-informed decisions for further management of women with mammographically suspicious or inconclusive findings, and contribute to future screening guidelines

Accuracy evaluation of radiographers screen reading mammograms

This thesis evaluated the accuracy of radiographers screen-reading mammograms. This was undertaken as a potential solution to current radiologist workforce shortages that may contribute to delays in women receiving their screening mammogram results. This large, well-designed Australian study undertook extensive analysis and imparts evidence that even prior to any formal reading training, radiographers have good accuracy levels when screen-reading mammograms. It is expected that with formal screen-reading training these accuracy levels will further improve, such that radiographers have the potential to be one of the two screen-readers within the BreastScreen Australia program, contributing to timeliness and improved accuracy outcomes

Recall Rates in Screening Mammography: Variability in Performance and Decisions

Having a high recall rate may increase the probability of cancer being detected earlier, however it also has been related to increased false positive decisions, causing significant psychological and economical costs for both screened women and the mammography screening service. Therefore, the purpose of this thesis is to explore the impact of various recall rates on breast radiologists’ performance in a laboratory setting. Methods This study was designed to encompass two aspects 1) the effect of setting varying recall rates on the performance of breast radiologists in screening mammography 2) types of mammographic appearances of breast cancer are more likely to be missed at different recall rates. Five Australian breast radiologists were recruited to read one single test set of 200 mammographic cases (180 normal and 20 abnormal cases) over three different recall rate conditions: free recall, 15% and 10%. These radiologists were tasked with marking the location of suspicious lesions and providing a confidence. Results A significant decrease in radiologists’ performance was observed when reading at lower recall rates, with lower sensitivity (P=0.002), case location sensitivity (P=0.002) and ROC AUC (P=0.003). Reading at a lower recall rate had a significant increase in specificity (P=0.002). The second study of this thesis showed that breast radiologists demonstrated lower sensitivity and receiver ROC AUC for non-specific density (NSD) (P=0.04 and P=0.03 respectively) and mixed features (P=0.01 and P=0.04 respectively) when reading at 15% and 10% recall rates. No significant change was observed on cancer characterized with stellate masses (P=0.18 and P=0.54 respectively) and architectural distortion (P=1.00 and P=0.37 respectively). Conclusion Reducing the number of recalled cases to 10% significantly reduced breast radiologists’ performance. Stellate masses were likely to be recalled (90.0%) while NSDs were likely to be missed (45.6%) at reduced recall rates