Clinical impact of the use of additional ultrasonography in diagnostic breast imaging

Unnecessary ultrasonography as supplier-induced demand in diagnosis of primary breast cancer in Iran: A cross-sectional study

BACKGROUND

Supplier-induced demand (SID) refers to the concept that healthcare providers may deliver services that are not medically necessary to patients. An estimation of the extent to which this event has occurred can be insightful for policymaking and guiding health and insurance systems. This study aimed to investigate the extent of SID when performing a diagnostic ultrasonography for primary breast cancer patients and its relationship with socioeconomic factors in Iran.

METHODS

Data were obtained using questionnaires from 334 patients referred to the Cancer Research Center. To identify the patients who were candidates for undergoing a necessary diagnostic US, we employed the international clinical guidelines with confirmation of our expert panelists. With their assistance, a comprehensive index was created to screen those 'most probably affected by SID'.

RESULTS

55.9% had undergone an unnecessary diagnostic ultrasonography, and thus were most probably affected by SID. A significant association between socioeconomic factors (education, occupation, and supplemental health insurance) and SID was confirmed (p value ≤ 0.001, 0.002, and 0.039, respectively).

CONCLUSION

This study supports the SID hypothesis and the unnecessary demand for diagnostic ultrasonography in primary breast cancer. Also, our evidence indicates imposing excessive costs that can positively influence the policymakers' decision-making in the healthcare systems.

Non-calcified ductal carcinoma in situ of the breast: comparison of diagnostic accuracy of digital breast tomosynthesis, digital mammography, and ultrasonography

BACKGROUND

To retrospectively compare the diagnostic accuracy of digital breast tomosynthesis (DBT), digital mammography (DM), and ultrasonography (US) in non-calcified ductal carcinoma in situ (DCIS, include DCIS with micro-invasion).

PATIENTS AND METHODS

Ninety-eight patients with non-calcified DCIS (include DCIS with micro-invasion) were enrolled in our study. Breast carcinoma in situ was confirmed by surgical pathologic evaluation. Our Institutional Review Board granted approval and the participating women provided written informed consent. The imaging findings were evaluated according to the Breast Imaging Reporting and Data System (BI-RADS) of the American College of Radiology (ACR) by comparing the differences in the detection rate and diagnostic accuracy among the three techniques in all cases, in dense breasts, and in non-dense breasts.

RESULTS

The detection rates of DBT, DM, and US for non-calcified DCIS in all cases were 83.7, 68.4, and 94.9%, respectively, and in patients with dense breasts were 81.2, 63.8, and 95.0%. The detection rate of US was higher than DBT, which, in turn, was higher than DM both in all cases and in dense breasts. Pairwise comparisons among the three techniques showed that the differences were statistically significant (P = 0.000 and P = 0.000, respectively). The experts identified a case as abnormal for all criteria (BI-RADS score of 4B-5) in 68.4% of ratings using DBT, 43.9% of ratings using DM, and 66.3% of ratings using US; for dense breasts, the positive identification rates were 62.5% of ratings using DBT, 41.2% of ratings using DM, and 61.2% of ratings using US. The diagnostic accuracy of DBT and US was significantly higher than that of DM in all cases (P = 0.001 and P = 0.006, respectively) and in dense breasts (P = 0.007 and P = 0.011, respectively). The diagnostic accuracy of DBT was slightly higher than US in all cases and in dense breasts, but the difference was not statistically significant (P = 0.761 and P = 0.871, respectively). By DBT, most non-calcified cases of DCIS presented as a mass lesion (54.9%) with an irregular shape (46.7%), indistinct margin (53.3%), and isodense composition (71.1%). Using US, 72 of 93 patients (77.4%) were shown to have a mass. Most mass lesions had an irregular shape (83.3%), indistinct margin (55.5%), and parallel the skin (82.8%).

CONCLUSION

DBT and US gave better detection rates and diagnostic accuracy for non-calcified DCIS compared with DM in all cases and in dense breasts. The detection rate of DBT was lower than that of US in all cases and in dense breasts. The diagnostic accuracy of DBT was slightly higher than that of US in all cases and in dense breasts, but the difference was not statistically significant. Imaging findings for non-calcified DCIS were relatively non-specific.

Screening Ultrasound in Women with Negative Mammography: Outcome Analysis

PURPOSE

To show the results of an audit of screening breast ultrasound (US) in women with negative mammography in a single institution and to analyze US-detected cancers within a year and interval cancers.

MATERIALS AND METHODS

During the year of 2006, 1974 women with negative mammography were screened with US in our screening center, and 1727 among them had pathologic results or any follow up breast examinations more than a year. We analyzed the distribution of Breast Imaging Reporting and Data System (BI-RADS) category and the performance outcome through follow up.

RESULTS

Among 1727 women (age, 30-76 years, median 49.5 years), 1349 women (78.1%) showed dense breasts on mammography, 762 (44.1%) had previous breast US, and 25 women (1.4%) had a personal history of breast cancers. Test negatives were 94.2% (1.627/1727) [BI-RADS category 1 in 885 (51.2%), 2 in 742 (43.0%)]. The recall rate (=BI-RADS category 3, 4, 5) was 5.8%. Eight cancers were additionally detected with US (yield, 4.6 per 1000). The sensitivity, specificity, and positive predictive value (PPV1, PPV2) were 88.9%, 94.6%, 8.0%, and 28.0%, respectively. Eight of nine true positive cancers were stage I or in-situ cancers. One interval cancer was stage I cancer from BI-RADS category 2.

CONCLUSION

Screening US detected 4.6 additional cancers among 1000. The recall rate was 5.8%, which is in lower bound of acceptable range of mammography (5-12%), according to American College of Radiology standard.

Characterization of breast lesions: comparison of digital breast tomosynthesis and ultrasonography

Objective

To compare the diagnostic performance of digital breast tomosynthesis (DBT) and conventional breast ultrasound (US) to characterize breast lesions as benign or malignant.

Materials and Methods

A total of 332 women, presenting for screening examinations or for breast biopsy between March and June 2012 were recruited to undergo digital mammography (DM), DBT, and breast US examination. Among them, 113 patients with 119 breast lesions depicted on DM were finally included. Three blinded radiologists performed an enriched reader study and reviewed the DBT and US images. Each reader analyzed the lesions in random order, assigned Breast Imaging Reporting and Data System (BI-RADS) descriptors, rated the images for the likelihood of malignancy (%) and made a BI-RADS final assessment. Diagnostic accuracy, as assessed by the area under the receiver operating characteristic curve, sensitivity, and specificity of DBT and US were compared.

Results

Among the 119 breast lesions depicted on DM, 75 were malignant and the remaining 44 were benign. The average diagnostic performance for characterizing breast lesions as benign or malignant in terms of area under the curve was 0.899 for DBT and 0.914 for US (p = 0.394). Mean sensitivity (97.3% vs. 98.7%, p = 0.508) and specificity (44.7% vs. 39.4%, p = 0.360) were also not significantly different.

Conclusion

Digital breast tomosynthesis may provide similar reader lesion characterization performance to that of US for breast lesions depicted on DM.

Mammography in combination with breast ultrasonography versus mammography for breast cancer screening in women at average risk

BACKGROUND

Breast cancer is the most common malignant disease diagnosed in women worldwide. Screening with mammography has the ability to detect breast cancer at an early stage. The diagnostic accuracy of mammography screening largely depends on the radiographic density of the imaged breasts. In radiographically dense breasts, non-calcified breast cancers are more likely to be missed than in fatty breasts. As a consequence, some cancers are not detected by mammography screening. Supporters of adjunct ultrasonography to the screening regimen for breast cancer argue that it might be a safe and inexpensive approach to reduce the false negative rates of the screening process. Critics, however, are concerned that performing supplemental ultrasonography on women at average risk will also increase the rate of false positive findings and can lead to unnecessary biopsies and treatments.

OBJECTIVES

To assess the comparative effectiveness and safety of mammography in combination with breast ultrasonography versus mammography for breast cancer screening for women at average risk of breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group's Specialised Register, MEDLINE (via OvidSP) and EMBASE up until February 2012.To detect ongoing or unpublished studies, we searched the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov and the National Cancer Institute's clinical trial database until June 2012. In addition, we conducted grey literature searches using the following sources: OpenGrey; National Institute of Health RePORTER; Health Services Research Projects in Progress (HSRPROJ); Hayes, Inc. Health Technology Assessment; The New York Academy of Medicine's Grey Literature Index and Conference Papers Index.

SELECTION CRITERIA

For efficacy, we considered randomised controlled trials (RCTs), with either individual or cluster randomisation, and prospective, controlled non-randomised studies with a low risk of bias and a sample size of at least 500 participants.In addition to studies eligible for efficacy, we considered any controlled, non-randomised study with a low risk of bias and a study size of at least 500 participants for the assessment of harms.Our population of interest were women between the ages of 40 and 75 years who were at average risk for breast cancer.

DATA COLLECTION AND ANALYSIS

Two review authors screened abstracts and full-text publications against the inclusion criteria. None of the studies met our inclusion criteria.

MAIN RESULTS

Our review did not detect any controlled studies on the use of adjunct ultrasonography for screening in women at average risk for breast cancer. One ongoing randomised controlled trial was identified (J-START, Japan).

AUTHORS' CONCLUSIONS

Presently, there is no methodologically sound evidence available justifying the routine use of ultrasonography as an adjunct screening tool in women at average risk for breast cancer.

An observational study using a national administrative database to determine the impact of hospital volume on compliance with clinical practice guidelines

BACKGROUND

Little information is available on the relationship between hospital volume and compliance with clinical practice guidelines (CPGs).

OBJECTIVES

To investigate the relationship between hospital volume and compliance with CPGs using a Japanese administrative database.

DESIGN AND SUBJECTS

This was an observational study that included 60,842 patients with acute cholangitis from 829 hospitals in Japan.

MEASURES

Hospital volume was categorized into the following 3 groups based on the number of cases of acute cholangitis during the study period: low-volume hospitals (LVHs; n = 20,869), medium-volume hospitals (MVHs; n = 18,387), and high-volume hospitals (HVHs; n = 21,586). We further collected patient data with regard to CPGs for acute cholangitis, and counted the number of recommendations that had been complied with for each patient. CPGs compliance score was defined as the rate of compliance with these recommendations for each patient (range, 0-10). Aggregated CPGs compliance score was measured according to hospital volume.

RESULTS

Mean CPGs compliance score in HVHs was significantly higher than that in MVHs and LVHs (6.8 ± 1.6 vs. 5.6 ± 1.5 vs. 3.9 ± 1.4, respectively; P < 0.001). Multiple linear regression analysis revealed that hospital volume was most significantly associated with CPGs compliance score. The standardized coefficient for CPGs compliance score in HVHs was 0.689, whereas that of MVHs was 0.366 (P < 0.001).

CONCLUSIONS

This study demonstrated that hospital volume was significantly associated with compliance with CPGs and that the Japanese administrative database was a viable tool for the monitoring of compliance with CPGs.

Diagnostic performance of breast technologists in reading mammograms in a clinical patient population

PURPOSE

In the setting of an increasing workload for radiologists, this study focuses on the feasibility of skill mixing in breast imaging in a hospital radiology department.

METHODS

Two radiological technologists with more than 10 years of experience in performing mammograms were trained in prereading mammograms to select the cases that require further evaluation by a radiologist. Mammograms of consecutive patients were independently evaluated by the technologists, next to the standard clinical interpretation by the radiologist on duty. Mammographic findings were recorded and a BI-RADS classification was assigned for each breast. Different prereading scenarios were analysed using clinical decision rules. Two different cut-off points of BI-RADS classifications were applied to the data. Analysis was performed for the overall clinical patient population as well as for a subgroup of patients with no immediate indication for further work-up.

RESULTS

Mammograms of 1994 patients were evaluated. In total, 93 breast cancers were found in 91 patients (prevalence 4.6%). Sensitivity and specificity in selecting mammographic findings (cut-off point between BI-RADS 1 and BI-RADS 0, 2-5 and the radiologist's diagnosis as reference standard) was 98% and 74% for technologist 1 and 98% and 78% for technologist 2. In distinguishing normal and benign mammograms from those with abnormalities that are probably benign, suspicious or highly suggestive for malignancy (cut-off point BI-RADS 1-2 and BI-RADS 0, 3-5 and pathology results as reference standard), sensitivity decreased to 89% and 91% respectively. Specificity increased to 82% for both technologists. In a subgroup of 1389 patients with no immediate indication for additional imaging with the involvement of a radiologist, technologists obtained a mean sensitivity and specificity of 98% and 77% in detecting mammographic findings, and a mean sensitivity and specificity of 78% and 88% in detecting suspicious abnormalities.

CONCLUSIONS

The employment of technologists in prereading mammograms seems to be an effective working strategy in daily clinical practice. However, its position in clinical practice remains indistinct as a continuous availability of radiologists still needs to be guaranteed. Nevertheless, as a substantial proportion of mammograms could be evaluated without the attention of a radiologist, the employment of technologists in prereading mammograms seems a promising new working strategy.

Costs and effects of using specialized breast technologists in prereading mammograms in a clinical patient population

Objectives: The aim of this study was to assess the costs and effects of using specialized breast technologists in prereading mammograms to reduce the increasing workload of radiologists in daily clinical practice. Mammography is the most widely used imaging modality for early detection and diagnosis of breast cancer.

Methods: A total of 1389 mammograms of consecutive patients were evaluated by two technologists trained in mammogram interpretation. The costs and effects of four different experimental strategies of prereading mammograms by technologists were analyzed by decision analytic modeling and compared with the conventional strategy of standard evaluation by the radiologist on duty.

Results: Overall, the employment of technologists in this patient population resulted in a potential time saving up to 73 percent (1019/1389) for the radiologist. No additional false-negative imaging results were found as compared to the conventional strategy. The total diagnostic costs in the conventional strategy were determined at €150,602. The experimental strategies resulted in cost savings up to 17.2 percent (range, €122,494–€139,781).

Conclusions: The employment of technologists in prereading mammograms in a clinical patient population could be effective to reduce the workload of radiologists without jeopardizing the detection of malignancies. Furthermore, diagnostic costs can be reduced considerably.

Comparative accuracy of mammography and ultrasound in women with breast symptoms according to age and breast density

Breast cancer is the most common cancer and the second most common cause of death from cancer in women.The aim of this studywas to determine which is more accurate imaging test mammography or ultrasound for diagnosis of breast cancer based on the women's age and breast density. We examined 546 patients with breast symptoms, by clinical breast examination, mammography and ultrasound. A total of 546 breast lesions were examined by histopathology analyses. Histopathology results revealed the presence of 259 invasive cancers, and 287 benign lesions. Sensitivity varied significantly with age and breast density. In the 259 women who had both tests, ultrasound had a higher sensitivity than mammography in women younger than 45 years, whereas mammography had a higher sensitivity than ultrasound in women older than 60 years. The sensitivity according to age was 52,1% for mammography and 72,6% for ultrasound. The specificity according to age was 88, 5% for ultrasound and 73, 9% for mammography. Comparing the sensitivity of mammography and ultrasound according to the breast density indicates that mammographic sensitivity was 82,2% among women with predominantly fatty breast, but 23.7% in women with heterogeneous dense breasts, with the increase of fibro glandular density the level of sensitivity with mammography decreases, while ultrasonographic sensitivity was 71,1% among women with predominantly fatty breast and 57,0% for heterogeneous dense breasts. Our data indicate that sensitivity and specificity of ultrasound was statistically significantly greater than mammography in patients with breast symptoms for the detection of breast cancer and benign lesions particularly in dense breast and in young women.