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Expo is the gathering place for the candy and snack. No more missed important software updates! UpdateStar 11 lets you stay up to date and secure with the software on your computer. Login. Welcome to Pearson Success. Net! We have made some important updates to Pearson Success. Net! As always, please contact us if you have any questions. Phone: 1- 8. 00- 2. Monday thru Friday 8am to 8pm EST)Email Support. Tomosynthesis and Mammography for Breast Screening . Single- institution studies have shown that adding tomosynthesis to mammography increases cancer detection and reduces false- positive results. Objective. To determine if mammography combined with tomosynthesis is associated with better performance of breast screening programs in the United States. Design, Setting, and Participants. Retrospective analysis of screening performance metrics from 1. Exposures. Period 1: digital mammography screening examinations 1 year before tomosynthesis implementation (start dates ranged from March 2. October 2. 01. 1 through the date of tomosynthesis implementation); period 2: digital mammography plus tomosynthesis examinations from initiation of tomosynthesis screening (March 2. October 2. 01. 2) through December 3. Main Outcomes and Measures. Recall rate for additional imaging, cancer detection rate, and positive predictive values for recall and for biopsy. Results. A total of 4. With digital mammography, 2. With digital mammography + tomosynthesis, 1. Model- adjusted rates per 1. CI, 8. 9- 1. 24) with digital mammography vs 9. CI, 7. 3- 1. 08) with digital mammography + tomosynthesis; difference, –1. CI, –1. 8 to –1. 4; P < . CI, 1. 5. 4- 2. 0. CI, 1. 6. 6- 2. 2. CI, 0. 4- 2. 1; P = . CI, 3. 8- 4. 7) with digital mammography vs 5. CI, 4. 9- 6. 0) with digital mammography + tomosynthesis; difference, 1. CI, 0. 8- 1. 6; P < . CI, 2. 5- 3. 2) with digital mammography vs 4. CI, 3. 7- 4. 5) with digital mammography + tomosynthesis; difference, 1. CI, 0. 8- 1. 6; P < . The in situ cancer detection rate was 1. CI, 1. 2- 1. 6) per 1. Adding tomosynthesis was associated with an increase in the positive predictive value for recall from 4. CI, 1. 7%- 2. 5%; P < . CI, 3. 0%- 7. 0%; P < . Conclusions and Relevance. Addition of tomosynthesis to digital mammography was associated with a decrease in recall rate and an increase in cancer detection rate. Further studies are needed to assess the relationship to clinical outcomes. By identifying a subset of cancers diagnosed before they reach clinical presentation, intervention is more likely to result in long- term survival. Despite this benefit, mammography has drawn criticism for excessive false- positive results, limited sensitivity, and the potential of overdiagnosis of clinically insignificant lesions. Incremental improvements in mammography have been realized through development of full- field digital imaging. Tomosynthesis involves image acquisition from an x- ray source that moves over an arc of excursion with reconstruction into thin slices to minimize the influence of overlapping breast structures. This data set can be acquired simultaneously with a conventional digital mammogram. In 2. 01. 1, tomosynthesis was approved by the US Food and Drug Administration (FDA) to be used in combination with standard digital mammography for breast cancer screening. This combined mode (digital mammography + tomosynthesis) addresses the primary limitations of conventional screening mammography by increasing conspicuity of invasive cancers while concomitantly reducing false- positive results. Total radiation dose when tomosynthesis is added is approximately 2 times the current digital mammography dose but remains well below the limits defined by the FDA. The reconstruction of a generated 2- dimensional image from the tomosynthesis data set, a technology recently approved by the FDA, should further address concerns regarding dose. Performance metrics for radiologists such as recall and cancer detection rates have been established to monitor screening outcomes, which in turn enable breast centers to assess the effectiveness of mammographic screening. Supplemental screening modes such as magnetic resonance imaging and ultrasound have demonstrated the ability to improve cancer detection but have failed to simultaneously reduce false- positive results. In this multicenter analysis, the performance of digital mammography + tomosynthesis was compared with that of digital mammography alone across a spectrum of radiology practices in the United States. This study compared performance of breast cancer screening before and after introduction of tomosynthesis at 1. Period 1 included 1 full year of screening with digital mammography alone, ending on the date of tomosynthesis introduction at each institution. Period 2 included screening with digital mammography + tomosynthesis until December 3. Individual institutions’ start dates for screening with digital mammography + tomosynthesis ranged from March 2. October 2. 01. 2. The analysis included the following performance metrics: recall rate (proportion of patients requiring additional imaging based on a screening examination result), cancer detection rate (proportion of patients with a screen- detected breast cancer), positive predictive value (PPV) for recall (proportion of patients recalled after screening who were diagnosed as having breast cancer) and PPV for biopsy (proportion of patients undergoing biopsies who were diagnosed as having breast cancer). Participating Institutions and Patient Population. Institutions performing screening with tomosynthesis were sent a questionnaire in August 2. Institutions expecting to complete 5. All 1. 3 invited sites participated and used the same equipment (Selenia Dimensions, Hologic), the only FDA- approved device at the time. Data Collection. Each participating institution provided aggregate data for all screening examinations, additional imaging studies, and relevant biopsy results. Submitted data from each institution were derived from records used to audit annual performance outcomes to maintain FDA compliance for screening mammography facilities. Recall rates were determined for each institution based on the initial interpretation of screening examinations. If a biopsy was recommended and performed within 1. A 1. 20- day interval was chosen to allow reasonable time for patients to complete the diagnostic workup but not include patients who were presenting for a 6- month follow up—a standard interval for short- term reevaluation in breast imaging. Cancers were identified as invasive or ductal carcinoma in situ (DCIS); cancers containing mixed invasive and in situ components were classified as invasive. Cancers not of primary breast origin, such as lymphomas and metastases, were excluded from analysis. We report the rate of screen- detected cancers and proportion of recalls per 1. Because data on interval cancers were not available, absolute sensitivity and specificity could not be calculated. A power analysis based on results showing a 2. With 6. 5 0. 00 cases in each period and the magnitude of observed change in the single- institution study, the multicenter study would have 8. Because sites contributed different numbers of cases during the 2 study periods, the primary analysis adjusts for site effect. Adjusting for site as a random effect allows for the possibility that patient outcomes within the same site are correlated, assuming that study patients are not fully independent observations. Specifically, additive and multiplicative mixed models using SAS PROC MIXED and NLMIXED (SAS, version 9. SAS Institute Inc) were used to estimate rates with screening method (digital mammography and digital mammography + tomosynthesis) as a fixed effect and site as a random effect. The log link function of the probability was specified. Adjusted rates and 9. All tests were 2- sided and P < . Tomosynthesis introduction at participating sites was nonuniform. Because of budgetary constraints, the majority of sites could not replace all mammography devices with tomosynthesis- capable units at once. Two sites did make a complete conversion, while the remaining sites maintained a hybrid environment with some patients receiving digital mammography alone during the second period. These concurrent digital mammography screening events were not included in the primary analysis. While no participating site intentionally targeted any specific population for tomosynthesis, the possibility of selection bias exists within the hybrid environments. Therefore, the analysis was repeated using all screened women (concurrent digital mammography alone plus digital mammography + tomosynthesis) in the digital mammography + tomosynthesis period to test if a significant change in cancer detection and recall rates was present between the preimplementation and postimplementation time frames. A total of 4. 54 8. Of the 4. 54 8. 50 examinations, 2. The average duration of the second period was 1. The volumes of digital mammography + tomosynthesis varied from 2. The mean age of patients undergoing imaging with digital mammography alone was 5. Table 2, Table 3, and Table 4 summarize recall, biopsy, and cancer detection rates for individual sites and for the entire cohort screened with digital mammography (period 1) and with digital mammography + tomosynthesis (period 2). The statistical model estimate is also shown. The recall rate per 1. CI, 8. 9- 1. 24) compared with 9. CI, 7. 3- 1. 08) with digital mammography + tomosynthesis. This represents an overall decrease in recall rate of –1. CI, –1. 8 to –1. 4; P < . Eleven of the 1. 3 sites observed a decrease in recall rate when screening with digital mammography + tomosynthesis. Two sites had recall rate increases of 1. The number of women undergoing biopsy who were recalled based on screening results was 5. The model- adjusted biopsy rate per 1. Table 3 and was 1. CI, 1. 5. 4- 2. 0. CI, 1. 6. 6- 2. 2. This represents an increase in biopsy rate for digital mammography + tomosynthesis of 1. CI, 0. 4- 2. 1; P = . Cases recommended for biopsy that were lost to follow- up comprised 4. Cancer was detected in 1. DCIS) with digital mammography and 9. DCIS) with digital mammography + tomosynthesis. The cancer detection rate per 1. CI, 3. 8- 4. 7) compared with 5. CI, 4. 9- 6. 0) when screening with digital mammography + tomosynthesis, representing an overall increase in cancer detection rate of 1.
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