Rates and causes of disagreement in interpretation of full-field digital mammography and film-screen mammography in a diagnostic setting

OBJECTIVE: This study was performed to determine the rates and causes of disagreements in interpretation between full-field digital mammography and film-screen mammography in a diagnostic setting. SUBJECTS AND METHODS: Patients undergoing diagnostic mammography were invited to participate in the digital mammography study. Three views, selected by the radiologist interpreting the film-screen mammography, were obtained in both film-screen mammography and digital mammography. Radiologists independently assigned a Breast Imaging Reporting and Data System (BI-RADS) category to the film-screen mammography and the digital mammography images. The BI-RADS categories were grouped into the general categories of agreement, partial agreement, or disagreement. A third and different radiologist reviewed all cases of disagreement, reached a decision as to management, and determined the primary cause of disagreement. RESULTS: Six radiologists reviewed digital mammography and film-screen mammography diagnostic images in a total of 1147 breasts in 692 patients. Agreement between digital mammography and final film-screen mammography assessment was present in 937 breasts (82%), partial agreement in 159 (14%), and disagreement in 51 (4%), for a kappa value of 0.29. The primary causes of disagreement were differences in management approach of the radiologists (52%), information derived from sonography or additional film-screen mammograms (34%), and technical differences between the two mammographic techniques (10%). CONCLUSION: Significant disagreement between film-screen mammography and digital mammography affecting follow-up management was present in only 4% of breasts. The most frequent cause of disagreement in interpretation was a difference in management approach between radiologists (interobserver variability). This source of variability was larger than that due to differences in lesion visibility between film-screen mammography and digital mammography.     

Comparison of full-field digital mammography to screen-film mammography with respect to diagnostic accuracy of lesion characterization in breast tissue biopsy specimens

RATIONALE AND OBJECTIVES: This study was performed to investigate whether full-field digital mammography (FFDM) is at least as accurate as screen-film mammography with respect to breast lesion characterization. MATERIALS AND METHODS: Seventy-nine breast surgical specimens were obtained by means of preoperative needle localization with surgical excision from 79 patients. The specimens were imaged with both screen-film mammography and FFDM. Six radiologists specialized in breast imaging analyzed both sets of images and characterized the visualized lesions on a five-point scale: 1, definitely not malignant; 2, probably not malignant; 3, possibly malignant; 4, probably malignant; and 5, definitely malignant. Receiver operating characteristic curve analysis of the data was then performed to assess for differences between modalities in the radiologists' ability to predict breast malignancy. RESULTS: The areas under the receiver operating characteristic curves for the prediction of breast malignancy in surgical biopsy specimens were not statistically significantly different for FFDM and screen-film mammography. CONCLUSION: The results demonstrate that with breast surgical specimens, FFDM is similar in diagnostic accuracy to screen-film mammography.     

Population-based mammography screening: comparison of screen-film and full-field digital mammography with soft-copy reading--Oslo I study

PURPOSE: To compare screen-film and full-field digital mammography with soft-copy reading in a population-based screening program. MATERIALS AND METHODS: Full-field digital and screen-film mammography were performed in 3,683 women aged 50-69 years. Two standard views of each breast were acquired with each modality. Images underwent independent double reading with use of a five-point rating scale for probability of cancer. Recall rates and positive predictive values were calculated. Cancer detection rates determined with both modalities were compared by using the McNemar test for paired proportions. Retrospective side-by-side analysis for conspicuity of cancers was performed by an external independent radiologist group with experience in both modalities. RESULTS: In 3,683 cases, 31 cancers were detected. Screen-film mammography depicted 28 (0.76%) malignancies, and full-field digital mammography depicted 23 (0.62%) malignancies. The difference between cancer detection rates was not significant (P =.23). The recall rate for full-field digital mammography (4.6%; 168 of 3,683 cases) was slightly higher than that for screen-film mammography (3.5%; 128 of 3,683 cases). The positive predictive value based on needle biopsy results was 46% for screen-film mammography and 39% for full-field digital mammography. Side-by-side image comparison for cancer conspicuity led to classification of 19 cancers as equal for probability of malignancy, six cancers as slightly better demonstrated at screen-film mammography, and six cancers as slightly better demonstrated at full-field digital mammography. CONCLUSION: There was no statistically significant difference in cancer detection rate between screen-film and full-field digital mammography. Cancer conspicuity was equal with both modalities. Full-field digital mammography with soft-copy reading is comparable to screen-film mammography in population-based screening.     

Two-modality mammography may confer an advantage over either full-field digital mammography or screen-film mammography

RATIONALE AND OBJECTIVES: We sought to compare the cancer detection rate and receiver operating characteristic (ROC) area under the curve of full-field digital mammography, screen-film mammography, and a combined technique that allowed diagnosis if a finding was suspicious on film mammography, on digital mammography, or both. MATERIALS AND METHODS: We used the data originally analyzed by Lewin and associates in 2002. In that trial, 6,736 paired full-field and digital mammograms were performed in 4,489 women. We used parametric and nonparametric tests to compare the area under the curve for ROC scores of film-screen only, digital mammography only, and the combined test. We used McNemar's test for paired proportions to compare the cancer detection rates. RESULTS: With the parametric test, neither the difference in the area under the curve between the film and combined nor the difference between the digital and combined ROC curves was significant at the Bonferroni-corrected 0.025 alpha level (film versus combined difference = 0.0563, P = .0712; digital versus combined difference = 0.0894, P = .0455). The nonparametric test showed that there was a significant difference between both film and combined (difference = 0.073, P = .008) and digital versus combined ROC curves (difference = 0.1164, P = .0008). The continuity-corrected McNemar's test showed a significant increase in the proportion of cancers detected by the combined modality over film (chi(2) = 7.111, df = 1, P = .0077), and over digital (chi(2) = 12.071, df = 1, P = .0005). CONCLUSION: Using two mammograms, one film and one digital, significantly increases the detection of breast cancer.     

Image quality, lesion detection, and diagnostic efficacy in digital mammography: full-field digital mammography versus computed radiography-based mammography using digital storage phosphor plates

OBJECTIVE: To compare image quality, the lesion detection, and the diagnostic efficacy of full-field digital mammography (FFDM) and computed radiography-based mammography using digital storage phosphor plates (DSPM) in the evaluation of breast lesions. MATERIALS AND METHODS: In this prospective study, 150 patients with suspicious breast lesions underwent FFDM and DSPM. Nine aspects of image quality (brightness, contrast, sharpness, noise, artifacts, and the detection of anatomic structures, i.e., skin, retromamillary space, glandular tissue, and calcifications) were evaluated by five radiologists. In addition, the detection of breast lesions and the diagnostic efficacy, based on the BI-RADS classification, were evaluated with histologic and follow-up correlation. RESULTS: For contrast, sharpness, and the detection of all anatomic structures, FFDM was rated significantly better (p<0.05). Mass lesions were equally detected, whereas FFDM detected more lesions consisting of calcifications (85 versus 75). DSPM yielded two false-negative results. Both lesions were rated BI-RADS 4 with FFDM, but BI-RADS 2 with DSPM. Both were invasive carcinoma at histology. The sensitivity, specificity, PPV, NPV, and accuracy of FFDM were 1.0, 0.397, 0.636, 1.0, and 0.707, compared to 0.974, 0.397, 0.630, 0.935, and 0.693 of DSPM. CONCLUSION: Based on image quality parameters, FFDM is, in part, significantly better than DSPM. Furthermore, the detection of breast lesions with calcifications is favorable with FFDM. However, the diagnostic efficacy of FFDM and DSPM was equal. The interpretation of the false-negative results suggests that the perception and characterization of breast lesions is not defined solely by the digital mammography system but is strongly influenced by the radiologist, who is one of the determinants in the interpretation of breast imaging.     

Breast lesion detection and classification: comparison of screen-film mammography and full-field digital mammography with soft-copy reading--observer performance study

PURPOSE: To retrospectively compare screen-film and full-field digital mammography with soft-copy interpretation for reader performance in detection and classification of breast lesions in women in a screening program. MATERIALS AND METHODS: Regional ethics committee approved the study; signed patient consents were obtained. Two-view mammograms were obtained with digital and screen-film systems at previous screening studies. Six readers interpreted images. Interpretation included Breast Imaging Reporting and Data System (BI-RADS) and five-level probability-of-malignancy scores. A case was one breast, with two standard views acquired with both screen-film mammography and digital mammography. The standard for an examination with normal findings was classification of normal (category 1) assigned by two independent readers; for cases with benign findings, the standard was benign results at diagnostic work-up in patients who were recalled. Cases with normal or benign findings that manifested as neither interval cancer nor as cancer at subsequent screening were considered the standard. All cancers were confirmed histologically. Images were interpreted by readers in two sessions 5 weeks apart; the same case was not seen twice in any session. Receiver operating characteristic (ROC) analysis and, for a given true-positive fraction, 2 x 2 table analysis and the McNemar test were used. For binary outcome, classification of BI-RADS category 3 or higher was defined as positive for cancer. RESULTS: Cases with proved findings (n = 232) were displayed: 46 with cancers, 88 with benign findings, and 98 with normal findings. ROC analysis for all readers and all cases revealed a higher area under ROC curve (A(z)) for digital mammography (0.916) than for screen-film mammography (0.887) (P = .22). Five of six readers had a higher performance rating with digital mammography; one of five demonstrated a significant difference in favor of digital mammography with A(z) values; two showed a significant difference in favor of digital mammography with ROC analysis for a given false-positive fraction (P = .01 and .03, respectively). For cases with cancer, digital mammography resulted in correct classification of an average of three additional cancers per reader. For digital versus screen-film mammography, 2 x 2 table analysis for cancers revealed a higher true-positive rate; for benign masses, a higher true-negative rate. Neither of these differences nor any others from analysis of subgroups between the modalities were significant. CONCLUSION: Digital mammography allowed correct classification of more breast cancers than did screen-film mammography. A(z) value was higher for digital mammography; this difference was not significant.     

Contrast-enhanced digital mammography: initial clinical experience

PURPOSE: To investigate the potential of using intravenous contrast material with full-field digital mammography to facilitate the detection and characterization of lesions in the breast. MATERIALS AND METHODS: Twenty-two women scheduled for biopsy because they were suspected of having abnormalities at breast imaging underwent imaging with contrast material-enhanced digital mammography. Six sequential images of the affected breast were obtained, with a contrast agent injected intravenously between the time the first and second images were obtained. Image processing included registration and logarithmic subtraction. Lesions were evaluated for the presence, morphology, and kinetics of enhancement. Lesion type, size, and pathologic findings were correlated with the findings at contrast-enhanced digital mammography. RESULTS: At contrast-enhanced digital mammography, enhancement was observed in eight of 10 patients with biopsy-proved cancers. In one case of ductal carcinoma in situ and one case of invasive ductal carcinoma, enhancement was not observed. No enhancement was seen in seven of 12 cases in which lesions were suspected of being malignant at initial imaging but were benign. Morphology generally correlated with the pathologic diagnosis. The kinetics of lesion enhancement showed similarity to that seen with gadolinium-enhanced magnetic resonance imaging but was not consistent. CONCLUSION: The results of this preliminary study suggest that contrast-enhanced digital mammography potentially may be useful in identification of lesions in the mammographically dense breast. Further investigation of contrast-enhanced digital mammography as a diagnostic tool for breast cancer is warranted.     

Digital mammography: what do we and what don’t we know?

High-quality full-field digital mammography has been available now for several years and is increasingly used for both diagnostic and screening mammography. A number of different detector technologies exist, which all have their specific advantages and disadvantages. Diagnostic accuracy of digital mammography has been shown to be at least equivalent to film-screen mammography in a general screening population. Digital mammography is superior to screen-film mammography in younger women with dense breasts due to its ability to selectively optimize contrast in areas of dense parenchyma. This advantage is especially important in women with a genetic predisposition for breast cancer, where intensified early detection programs may have to start from 25 to 30 years of age. Tailored image processing and computer-aided diagnosis hold the potential to further improve the early detection of breast cancer. However, at present no consensus exists among radiologists on which processing is optimal for digital mammograms. Image processing may also vary significantly among vendors with so far limited interoperability. This review aims to summarize the available information regarding the impact of digital mammography on workflow and breast cancer diagnosis.     

Full-field digital mammography designed as a complete system.

Although mammography is currently considered by many to be the best tool for the early detection of breast cancer, conventional film-screen imaging is still far from perfect. A fundamental limitation of film-screen mammography is the fact that the detection, display and storage devices are one and the same, making it impossible to separately optimize each device. In addition to a potentially equivalent or better image quality compared to the film-screen technology, full-field digital mammography (FFDM) will provide the radiologist with numerous advantages: digital image management, digital data transfer and new medical applications. Nevertheless, to fulfil the potential of digital mammography, an FFDM unit must not only provide an outstanding technology for X-ray detection, but should be designed as a complete system. Each component of the FFDM system should be designed to provide or to increase the current image quality, the current ease of use and the current throughput: the X-ray tube, the gantry, the image receptor packaging, the detector, the acquisition electronics, the softcopy review workstation, the user interface, as well as the network capabilities.     

Clinical comparison of full-field digital mammography and screen-film mammography for detection of breast cancer

OBJECTIVE: The purpose of this work is to compare full-field digital mammography and screen-film mammography for the detection of breast cancer in a screening population. SUBJECTS AND METHODS: Full-field digital mammography was performed in addition to screen-film mammography in 6736 examinations of women 40 years old and older presenting for screening mammography at either of two institutions. Two views of each breast were acquired with each technique. The digital and screen-film mammograms were each interpreted independently. In addition to a clinical assessment, each finding was assigned a probability of malignancy for use in receiver operating characteristic analysis. In cases in which the digital and screen-film interpretations differed, a side-by-side analysis was performed to determine the reasons for the discrepancy. With few exceptions, findings detected on either technique were evaluated with additional imaging and, if warranted, biopsy. RESULTS: Additional evaluation was recommended on at least one technique in 1467 cases. These additional evaluations led to 181 biopsies and the detection of 42 cancers. Nine cancers were detected only on digital mammography, 15 were detected only on screen-film mammography, and 18 were detected on both. The difference in cancer detection is not statistically significant (p > 0.1). Digital mammography resulted in fewer recalls than did screenfilm mammography (799 vs 1007, p < 0.001). The difference between the receiver operating characteristic curve area for digital (0.74) and screen-film (0.80) mammography was not significant (p > 0.1). Reasons for discrepant interpretations of cancer were approximately equally distributed among those relating to lesion conspicuity, lesion appearance, and interpretation. CONCLUSION: No significant difference in cancer detection was observed between digital mammography and screen-film mammography. Digital mammography resulted in fewer recalls than did screen-film mammography.     

Diagnostic accuracy of Fischer Senoscan Digital Mammography versus screen-film mammography in a diagnostic mammography population

RATIONALE AND OBJECTIVES: To compare the diagnostic accuracy of the Fischer Senoscan Digital Mammography System with that of standard screen-film mammography in a population of women presenting for screening or diagnostic mammography. MATERIALS AND METHODS: Enrollment of patients took place at six different breast-imaging centers between 1997 and 1999. A total of 247 cases were selected for inclusion in the final reader study. All known cancer cases were included (111) from all six participating sites representing 45% of the total cases. The remaining 136 cases (55%) were randomly selected from all available benign or negative cases from three of the six sites. A complete case consisted of both a (unilateral or bilateral) digital and screen-film mammogram of the same patient. Eight radiologists interpreted the cases in laser-printed digital and screen-film hardcopy formats. The study was designed to detect differences of 0.05 in the ROC area under the curve (AUC) between digital and screen-film radiologist interpretation performance. RESULTS: The average AUC for the Senoscan digital was 0.715 for the 8 readers. The average AUC for screen-film was 0.765. The difference AUC of -0.05 falls within the 95% confidence interval (-0.101, 0.002). The average sensitivity was 66% and specificity 67% for SenoScan full-field digital mammography. The average screen-film mammography sensitivity and specificity were 74% and 60%, respectively. CONCLUSION: No statistically significant difference in diagnostic accuracy between the Fischer Senoscan and screen-film mammography was detected in this study.     

Efficacy of storage phosphor-based digital mammography in diagnosis of breast cancer--comparison with film-screen mammography]

The aim of this study is to present efficacy of storage phosphor-based digital mammography (CR-mammography) in diagnosis of breast cancer. Ninety-seven cases with breast cancer including 44 cases less than 2 cm in macroscopic size (t1 cases) were evaluated using storage phosphor-based digital mammography (2000 x 2510 pixels by 10 bits). Abnormal findings on CR-mammography were detected in 86 cases (88.7%) of 97 women with breast cancer. Sensitivity of CR-mammography was 88.7%. It was superior to that of film-screen mammography. On t1 breast cancer cases, sensitivity on CR-mammography was 88.6%. False negative rate in t1 breast cancer cases was reduced by image processing using CR-mammography. To evaluate microcalcifications, CR-mammograms and film-screen mammograms were investigated in 22 cases of breast cancer proven pathologically the existence of microcalcifications and 11 paraffin tissue blocks of breast cancer. CR-mammography was superior to film-screen mammography in recognizing of microcalcifications. As regards the detectability for the number and the shape of microcalcifications, CR-mammography was equivalent to film-screen mammography. Receiver operating characteristic (ROC) analysis by eight observers was performed for CR-mammography and film-screen mammography with 54 breast cancer patients and 54 normal cases. The detectability of abnormal findings of breast cancer on CR-mammography (ROC area = 0.91) was better than that on film-screen mammography (ROC area = 0.88) (p less than 0.05). Efficacy of storage phosphor-based digital mammography in diagnosis of breast cancer was discussed and demonstrated in this study.     

高频超声与全数字化乳腺摄影联合诊断乳腺导管癌的临床应用

目的:探讨乳腺导管癌的高频超声表现,并评价高频超声联合全数字化乳腺摄影检查对乳腺导管癌的诊断价值。方法:分析46例经病理证实的乳腺导管癌的超声表现,与相应病理结果进行对比分析。46例患者均行高频超声和全数字乳腺摄影检查。结果:高频超声探及到肿块46例,诊断乳腺癌45例,诊断率达98%。全数字化乳腺摄影诊断乳腺癌46例,诊断率达100%。高频超声和全数字化摄影对乳腺导管癌检出率无差别且无统计学意义(P>0.05)。结论:高频超声与全数字化乳腺摄影联合应用,可提高乳腺癌诊断的敏感性和准确性。     

Digital mammography: An update

Digital mammography has increasingly replaced conventional film-screen mammography and has become the gold standard in combination with soft copy reading in diagnostic as well as screening settings. Large international multi-center trials were able to demonstrate at least equivalence and for some aspects superiority of digital over conventional mammography with regard to detectability of breast cancer, especially in pre/perimenopausal women, women younger than 50 years and generally in dense breasts. Especially the experienced reader may benefit form CAD with an increase of specificity. Additionally digital mammography offers options of advanced processing such as digital tomosynthesis and contrast enhanced mammography. The future of breast imaging will be fusion of different imaging systems (hybrid systems).     

ROC analysis comparing screen film mammography and digital mammography

PURPOSE: To compare the diagnosis performances of radiologists on screen film versus digital mammography. MATERIAL: and methods: Two sets of 123 mammograms, screen film mammography and storage phosphor digital mammography, are studied comparatively with ROC analysis. RESULTS: Phantom study show that conventional method give better scores for usual tension but the detectability of smaller microcalcification is equivalent. To obtain with digital technic the same conventional score you have to increase the radiation dose. Roc Curves, simulated "detection" mode showed that radiologists performed with higher accuracy with conventional system but this difference is weekly statistically significant. ROC Curves, simulated "diagnostic" mode showed the same results wit no statistically significant difference but when the decision to go to the biopsy is the gold standard, ROC Curves were essentially equivalent for both film screen and digital mammography system. The readers consistently considered the digital mammograms to be less suspicious for cancer findings. The agreement study as proposed by the FDA indicate that probability of a positive digital mammograms given a positive screen film is 75% (threshold value 90%) and the probability of a negative digital mammograms given a negative analog film is 85% (threshold value 85%). CONCLUSION: Analysis of specific discrepancies indicate that spatial resolution is an essential limiting factor for digital method but high resolution phosphor plate are interesting in imaging treated breast, radioluscent lesion, fatty benign tumor, hamartoma, intramammary lymph node, breast with prosthesis.     

Performance parameters for screening and diagnostic mammography: specialist and general radiologists

PURPOSE: To evaluate performance parameters for radiologists in a practice of breast imaging specialists and general diagnostic radiologists who interpret a large series of consecutive screening and diagnostic mammographic studies. MATERIALS AND METHODS: Data (ie, patient age; family history of breast cancer; availability of previous mammograms for comparison; and abnormal interpretation, cancer detection, and stage 0-I cancer detection rates) were derived from review of mammographic studies obtained from January 1997 through August 2001. The breast imaging specialists have substantially more initial training in mammography and at least six times more continuing education in mammography, and they interpret 10 times more mammographic studies per year than the general radiologists. Differences between specialist and general radiologist performances at both screening and diagnostic examinations were assessed for significance by using Student t and chi(2) tests. RESULTS: The study involved 47,798 screening and 13,286 diagnostic mammographic examinations. Abnormal interpretation rates for screening mammography (ie, recall rate) were 4.9% for specialists and 7.1% for generalists (P <.001); and for diagnostic mammography (ie, recommended biopsy rate), 15.8% and 9.9%, respectively (P <.001). Cancer detection rates at screening mammography were 6.0 cancer cases per 1,000 examinations for specialists and 3.4 per 1,000 for generalists (P =.007); and at diagnostic mammography, 59.0 per 1,000 and 36.6 per 1,000, respectively (P <.001). Stage 0-I cancer detection rates at screening mammography were 5.3 cancer cases per 1,000 examinations for specialists and 3.0 per 1,000 for generalists (P =.012); and at diagnostic mammography, 43.9 per 1,000 and 27.0 per 1,000, respectively (P <.001). CONCLUSION: Specialist radiologists detect more cancers and more early-stage cancers, recommend more biopsies, and have lower recall rates than general radiologists.     

Digital breast tomosynthesis versus digital mammography: a clinical performance study

Objective

To compare the clinical performance of digital breast tomosynthesis (DBT) with that of full-field digital mammography (FFDM) in a diagnostic population.

Methods

The study enrolled 200 consenting women who had at least one breast lesion discovered by mammography and/or ultrasound classified as doubtful or suspicious or probably malignant. They underwent tomosynthesis in one view [mediolateral oblique (MLO)] of both breasts at a dose comparable to that of standard screen-film mammography in two views [craniocaudal (CC) and MLO]. Images were rated by six breast radiologists using the BIRADS score. Ratings were compared with the truth established according to the standard of care and a multiple-reader multiple-case (MRMC) receiver-operating characteristic (ROC) analysis was performed. Clinical performance of DBT compared with that of FFDM was evaluated in terms of the difference between areas under ROC curves (AUCs) for BIRADS scores.

Results

Overall clinical performance with DBT and FFDM for malignant versus all other cases was not significantly different (AUCs 0.851 vs 0.836, p?=?0.645). The lower limit of the 95% CI or the difference between DBT and FFDM AUCs was ?4.9%.

Conclusion

Clinical performance of tomosynthesis in one view at the same total dose as standard screen-film mammography is not inferior to digital mammography in two views.     

Comparison of full-field digital mammography and film-screen mammography: image quality and lesion detection

The objective of this study is to compare image quality and lesion detection for full field digital mammography (FFDM) and film-screen mammography (FSM). In 200 women we performed digital mammography of one breast and film-screen mammography of the other breast. Imaging parameters were set automatically. Image quality, visualization of calcifications and masses were rated by three readers independently. Mean glandular dose was calculated for both systems. We found no significant difference in mean glandular dose. Image quality was rated by reader A/B/C as excellent for FFDM in 153/155/167 cases and for FSM in 139/116/114 cases (p<0.03/0.001/0.001). Microcalcifications were detected by FFDM in 103/89/98 and by FSM in 76/76/76 cases (p<0.01/0.06/0.01). Detection of masses did not differ significantly. FFDM provided significantly better visibility of skin and nipple-areola region (p<0.01). FFDM demonstrated improved image quality compared with film-screen mammography. Microcalcification detection was also significantly better with the digital mammography system for two of the three readers.     

ROC curve analysis of lesion detectability on phantoms: comparison of digital spot mammography with conventional spot mammography

Although conventional screen--film mammography has excellent spatial resolution and is commonly used as a screening tool, certain inherent limitations prevent its further improvement. New digital mammography techniques, despite lower spatial resolution than screen--film mammography, may overcome these limitations. This study compared lesion detectability between charge coupled device-based digital spot mammography and conventional spot mammography. A total of 100 sets of images of specially designed breast phantoms was acquired, with variable background achieved by overlapping several layers of grapefruit fibre on a 4 cm thick lucite slab, using both modalities. 75 sets were "normal" images and 25 sets were images with simulated lesions. Four radiologists assessed the images according to a five-point confidence scale. The results were used to construct receiver operating characteristic curves. No statistical difference was observed between the two sets of curves for individual radiologists as well as pooled data. The lower spatial resolution of digital mammography was compensated for by its higher contrast sensitivity relative to conventional spot mammography.     

Performance benchmarks for screening mammography

PURPOSE: To retrospectively evaluate the range of performance outcomes of the radiologist in an audit of screening mammography by using a representative sample of U.S. radiologists to allow development of performance benchmarks for screening mammography. MATERIALS AND METHODS: Institutional review board approval was obtained, and study was HIPAA compliant. Informed consent was or was not obtained according to institutional review board guidelines. Data from 188 mammographic facilities and 807 radiologists obtained between 1996 and 2002 were analyzed from six registries from the Breast Cancer Surveillance Consortium (BCSC). Contributed data included demographic information, clinical findings, mammographic interpretation, and biopsy results. Measurements calculated were positive predictive values (PPVs) from screening mammography (PPV(1)), biopsy recommendation (PPV(2)), biopsy performed (PPV(3)), recall rate, cancer detection rate, mean cancer size, and cancer stage. Radiologist performance data are presented as 50th (median), 10th, 25th, 75th, and 90th percentiles and as graphic presentations by using smoothed curves. RESULTS: There were 2 580 151 screening mammographic studies from 1 117 390 women (age range, <30 to >/=80 years). The respective means and ranges of performance outcomes for the middle 50% of radiologists were as follows: recall rate, 9.8% and 6.4%-13.3%; PPV(1), 4.8% and 3.4%-6.2%; and PPV(2), 24.6% and 18.8%-32.0%. Mean cancer detection rate was 4.7 per 1000, and the mean size of invasive cancers was 13 mm. The range of performance outcomes for the middle 80% of radiologists also was presented. CONCLUSION: Community screening mammographic performance measurements of cancer outcomes for the majority of radiologists in the BCSC surpass performance recommendations. Recall rate for almost half of radiologists, however, is higher than the recommended rate.