Use of clinical history affects accuracy of interpretive performance of screening mammography

Gadolinium-based Contrast Agents Improve Detection of Recurrent Soft-Tissue Sarcoma at MRI

Purpose

To determine the diagnostic efficacy of gadolinium-based contrast agents for the detection of recurrent soft-tissue sarcoma compared with non-contrast-enhanced conventional MRI sequences.

Materials and Methods

A retrospective study of patients with soft-tissue sarcomas who were imaged from January 2009 to December 2014 was performed. MRI studies from 69 patients (mean age, 61 years ± 15 [standard deviation], 45 men) with recurrent soft-tissue sarcoma and 63 age-, sex-, and tumor-matched controls with positive findings (nonrecurrence) were presented to six musculoskeletal radiologists at a tertiary cancer center in three image groupings. Group 1 consisted of precontrast T1-weighted and fat-suppressed T2-weighted images (no contrast agent). Group 2 consisted of precontrast and postcontrast fat-saturated T1-weighted images. Group 3 consisted of precontrast and fat-saturated postcontrast T1- and fat-suppressed T2-weighted images. Images within these three groups contained either recurrent soft-tissue sarcomas or positive postoperative findings (nonsarcoma). The presentation order of the first two image sets was reversed for half the readers. The readers were asked to classify presence of tumor on a five-point scale. The average score from the readers was used as consensus score for each case, and a case was considered positive if the average score was less than 3. Receiver operating characteristic (ROC) analysis was performed using the average score for each image set.

Results

Assessment of the group 3 image set resulted in higher sensitivity (74%, 95% confidence interval [CI]: 62%, 83%) than the group 2 image set (64%, 95% CI: 51%, 75%), which was also more sensitive than the assessment of the group 1 images set (49%, 95% CI: 37%, 61%), with P = .02 for both. There was no significant difference in specificity between the three groups. The area under the ROC curve (AUC) for the assessment of group 1 was 0.78 (95% CI: 0.70, 0.86), which was significantly lower than that of group 2, 0.92 (95% CI: 0.87, 0.96) and group 3, 0.93 (95% CI: 0.88, 0.97), with P values of .0006 and < .0001, respectively. There was no difference between the AUCs of groups 2 and 3 (P = .58).

Conclusion

Gadolinium-based contrast agents improved diagnostic performance in detection of recurrent soft-tissue sarcoma. Addition of fat-saturated T2-weighted images provided modest improvement in sensitivity.Keywords: Efficacy Studies, MR-Contrast Agent, Oncology, Soft Tissues/Skin© RSNA, 2020.

Great expectations: minor differences in initial instructions have a major impact on visual search in the absence of feedback

Professions such as radiology and aviation security screening that rely on visual search-the act of looking for targets among distractors-often cannot provide operators immediate feedback, which can create situations where performance may be largely driven by the searchers' own expectations. For example, if searchers do not expect relatively hard-to-spot targets to be present in a given search, they may find easy-to-spot targets but systematically quit searching before finding more difficult ones. Without feedback, searchers can create self-fulfilling prophecies where they incorrectly reinforce initial biases (e.g., first assuming and then, perhaps wrongly, concluding hard-to-spot targets are rare). In the current study, two groups of searchers completed an identical visual search task but with just a single difference in their initial task instructions before the experiment started; those in the "high-expectation" condition were told that each trial could have one or two targets present (i.e., correctly implying no target-absent trials) and those in the "low-expectation" condition were told that each trial would have up to two targets (i.e., incorrectly implying there could be target-absent trials). Compared to the high-expectation group, the low-expectation group had a lower hit rate, lower false alarm rate and quit trials more quickly, consistent with a lower quitting threshold (i.e., performing less exhaustive searches) and a potentially higher target-present decision criterion. The expectation effect was present from the start and remained across the experiment-despite exposure to the same true distribution of targets, the groups' performances remained divergent, primarily driven by the different subjective experiences caused by each groups' self-fulfilling prophecies. The effects were limited to the single-targets trials, which provides insights into the mechanisms affected by the initial expectations set by the instructions. In sum, initial expectations can have dramatic influences-searchers who do not expect to find a target, are less likely to find a target as they are more likely to quit searching earlier.

Metastatic Versus Osteoporotic Vertebral Fractures on MRI: A Blinded, Multicenter, and Multispecialty Observer Agreement Evaluation

BACKGROUND

MRI is assumed to be valid for distinguishing metastatic vertebral fractures (MVFs) from osteoporotic vertebral fractures (OVFs). This study assessed (1) concordance between the image-based diagnosis of MVF versus OVF and the reference (biopsy or follow-up of >6 months), (2) interobserver and intraobserver agreement on key imaging findings and the diagnosis of MVF versus OVF, and (3) whether disclosing a patient's history of cancer leads to variations in diagnosis, concordance, or agreement.

PATIENTS AND METHODS

This retrospective cohort study included clinical data and imaging from 203 patients with confirmed MVF or OVF provided to 25 clinicians (neurosurgeons, radiologists, orthopedic surgeons, and radiation oncologists). From January 2018 through October 2018, the clinicians interpreted images in conditions as close as possible to routine practice. Each specialist assessed data twice, with a minimum 6-week interval, blinded to assessments made by other clinicians and to their own previous assessments. The kappa statistic was used to assess interobserver and intraobserver agreement on key imaging findings, diagnosis (MVF vs OVF), and concordance with the reference. Subgroup analyses were based on clinicians' specialty, years of experience, and complexity of the hospital where they worked.

RESULTS

For diagnosis of MVF versus OVF, interobserver agreement was fair, whereas intraobserver agreement was substantial. Only the latter improved to almost perfect when a patient's history of cancer was disclosed. Interobserver agreement for key imaging findings was fair or moderate, whereas intraobserver agreement on key imaging findings was moderate or substantial. Concordance between the diagnosis of MVF versus OVF and the reference was moderate. Results were similar regardless of clinicians' specialty, experience, and hospital category.

CONCLUSIONS

When MRI is used to distinguish MVF versus OVF, interobserver agreement and concordance with the reference were moderate. These results cast doubt on the reliability of basing such a diagnosis on MRI in routine practice.

"I'm Just Guessing These Answers!" An Evaluation of the (In)Accuracy of Patient-Reported Medical History Collected as Part of a Breast Imaging Program

INTRODUCTION

Hundreds of thousands of Ontario women receive breast screening imaging each year. The patient's medical history is a vital tool used to personalize breast screening approaches. This study evaluated the accuracy of self-reported medical and imaging history in patients about to receive breast imaging procedures in a large urban Canadian hospital. The patient experience with using a blank screening form vs. a novel prefilled screening form was also evaluated.

METHODS AND MATERIALS

The study was conducted in two phases. Phase 1 compared patient-reported information (via the blank screening form) to information previously captured in the Radiology Information and Picture Archiving Communication Systems to assess data accuracy. In phase 2, study questionnaires were used to collect data on the patients' experience with the screening form in two cohorts (between the blank and a novel prefilled screening form).

RESULTS

Data accuracy: for mammography (n = 60), 40% of the patients could accurately recall when and where their last mammogram was performed. For breast ultrasound (n = 43) and breast magnetic resonance imaging (n = 20), significantly fewer patients could accurately recall the date their last test was performed (14% and 10%, respectively). Of those who had previous breast surgery (n = 18), 100% were able to recall whether the surgery resulted in a benign or malignant diagnosis, and 61% were able to accurately recall the year they had the breast surgery.

PATIENT EXPERIENCE

Of the returned questionnaires, 65 provided feedback on the blank screening form while 55 provided feedback on the prefilled form. Ninety percent preferred to fill out the new prefilled screening form. The themes acknowledged a general improvement in the screening form, a decrease in frustration associated with having to recall their medical history, and the patients felt that the institution better understood their medical history.

CONCLUSIONS

The findings of this research indicate that asking patients to complete a blank medical screening form is a highly inaccurate method of gathering that important information. When that information was prefilled for the patient to review and update, patient frustration and stress were decreased, while satisfaction and confidence in the organization were increased.

Impact of Clinical History on Maximum PI-RADS Version 2 Score: A Six-Reader 120-Case Sham History Retrospective Evaluation

Purpose To assess the impact of clinical history on the maximum Prostate Imaging Recording and Data System (PI-RADS) version 2 (v2) score assigned to multiparametric magnetic resonance (MR) imaging of the prostate. Materials and Methods This retrospective cohort study included 120 consecutively selected multiparametric prostate MR imaging studies performed between November 1, 2016, and December 31, 2016. Sham clinical data in four domains (digital rectal examination, prostate-specific antigen level, plan for biopsy, prior prostate cancer history) were randomly assigned to each case by using a balanced orthogonal design. Six fellowship-trained abdominal radiologists independently reviewed the sham data, actual patient age, and each examination while they were blinded to interreader scoring, true clinical data, and histologic findings. Readers were told the constant sham histories were true, believed the study to be primarily investigating interrater agreement, and were asked to assign a maximum PI-RADS v2 score to each case. Linear regression was performed to assess the association between clinical variables and maximum PI-RADS v2 score designation. Intraclass correlation coefficients (ICCs) were obtained to compare interreader scoring. Results Clinical information had no significant effect on maximum PI-RADS v2 scoring for any of the six readers (P = .09-.99, 42 reader-variable pairs). Distributions of maximum PI-RADS v2 scores in the research context were similar to the distribution of the scores assigned clinically and had fair-to-excellent pairwise interrater agreement (ICC range: 0.53-0.76). Overall interrater agreement was good (ICC: 0.64; 95% confidence interval: 0.57, 0.71). Conclusion Clinical history does not appear to be a substantial bias in maximum PI-RADS v2 score assignment. This is potentially important for clinical nomograms that plan to incorporate PI-RADS v2 score and clinical data into their algorithms (ie, PI-RADS v2 scoring is not confounded by clinical data).

Breast cancer screening effect across breast density strata: A case-control study

Breast cancer screening is known to reduce breast cancer mortality. A high breast density may affect this reduction. We assessed the effect of screening on breast cancer mortality in women with dense and fatty breasts separately. Analyses were performed within the Nijmegen (Dutch) screening programme (1975-2008), which invites women (aged 50-74 years) biennially. Performance measures were determined. Furthermore, a case-control study was performed for women having dense and women having fatty breasts. Breast density was assessed visually with a dichotomized Wolfe scale. Breast density data were available for cases. The prevalence of dense breasts among controls was estimated with age-specific rates from the general population. Sensitivity analyses were performed on these estimates. Screening performance was better in the fatty than in the dense group (sensitivity 75.7% vs 57.8%). The mortality reduction appeared to be smaller for women with dense breasts, with an odds ratio (OR) of 0.87 (95% CI 0.52-1.45) in the dense and 0.59 (95% CI 0.44-0.79) in the fatty group. We can conclude that high density results in lower screening performance and appears to be associated with a smaller mortality reduction. Breast density is thus a likely candidate for risk-stratified screening. More research is needed on the association between density and screening harms.

Influences of Radiology Trainees on Screening Mammography Interpretation

PURPOSE

Participation of radiology trainees in screening mammographic interpretation is a critical component of radiology residency and fellowship training. The aim of this study was to investigate and quantify the effects of trainee involvement on screening mammographic interpretation and diagnostic outcomes.

METHODS

Screening mammograms interpreted at an academic medical center by six dedicated breast imagers over a three-year period were identified, with cases interpreted by an attending radiologist alone or in conjunction with a trainee. Trainees included radiology residents, breast imaging fellows, and fellows from other radiology subspecialties during breast imaging rotations. Trainee participation, patient variables, results of diagnostic evaluations, and pathology were recorded.

RESULTS

A total of 47,914 mammograms from 34,867 patients were included, with an overall recall rate for attending radiologists reading alone of 14.7% compared with 18.0% when involving a trainee (P < .0001). Overall cancer detection rate for attending radiologists reading alone was 5.7 per 1,000 compared with 5.2 per 1,000 when reading with a trainee (P = .517). When reading with a trainee, dense breasts represented a greater portion of recalls (P = .0001), and more frequently, greater than one abnormality was described in the breast (P = .013). Detection of ductal carcinoma in situ versus invasive carcinoma or invasive cancer type was not significantly different. The mean size of cancers in patients recalled by attending radiologists alone was smaller, and nodal involvement was less frequent, though not statistically significantly.

CONCLUSIONS

These results demonstrate a significant overall increase in recall rate when interpreting screening mammograms with radiology trainees, with no change in cancer detection rate. Radiology faculty members should be aware of this potentiality and mitigate tendencies toward greater false positives.

Who may benefit from preoperative breast MRI? A single-center analysis of 1102 consecutive patients with primary breast cancer

Several authors question the potential benefit of preoperative magnetic resonance imaging (MRI) against the background of possible overdiagnosis, false-positive findings, and unnecessary resections in patients with newly diagnosed breast cancer. In order to reveal a better selection of patients who should undergo preoperative MRI after histological confirmed breast cancer, the present analysis was implemented. We aimed to evaluate the influence of preoperative breast MRI in patients with newly diagnosed breast cancer to find subgroups of patients that are most likely to benefit from preoperative MRI by the detection of occult malignant foci. A total of 1102 consecutive patients who underwent treatment for primary breast cancer between 2002 and 2013 were retrospectively analyzed. All patients underwent triple assessment by breast ultrasound, mammography, and bilateral breast MRI. MRI findings not seen on conventional imaging that suggested additional malignant disease was found in 344 cases (31.2 %). Histological confirmed malignant foci were found in 223 patients (20.2 %) within the index breast and in 28 patients (2.5 %) in the contralateral breast. The rate of false-negative biopsies was 31 (2.8 %) and 62 (5.6 %), respectively. Premenopausal women (p = 0.024), lobular invasive breast cancer (p = 0.02) as well as patients with high breast density [American College of Radiology (ACR) 3 + 4; p = 0.01] were significantly associated with additional malignant foci in the index breast. Multivariate analysis confirmed lobular histology (p = 0.041) as well as the co-factors "premenopausal stage" and "high breast density (ACR 3+4)" (p = 0.044) to be independently significant. Previous studies revealed that breast MRI is a reliable tool for predicting tumor extension as well as for the detection of additional ipsilateral and contralateral tumor foci in histological confirmed breast cancer. In the present study, we demonstrate that especially premenopausal patients with high breast density as well as patients with lobular histology seem to profit from preoperative MRI.

The influence of mammographic technologists on radiologists' ability to interpret screening mammograms in community practice

RATIONALE AND OBJECTIVES

To determine whether the mammographic technologist has an effect on the radiologists' interpretative performance of screening mammography in community practice.

MATERIALS AND METHODS

In this institutional review board-approved retrospective cohort study, we included Carolina Mammography Registry data from 372 radiologists and 356 mammographic technologists from 1994 to 2009 who performed 1,003,276 screening mammograms. Measures of interpretative performance (recall rate, sensitivity, specificity, positive predictive value [PPV1], and cancer detection rate [CDR]) were ascertained prospectively with cancer outcomes collected from the state cancer registry and pathology reports. To determine if the mammographic technologist influenced the radiologists' performance, we used mixed effects logistic regression models, including a radiologist-specific random effect and taking into account the clustering of examinations across women, separately for screen-film mammography (SFM) and full-field digital mammography (FFDM).

RESULTS

Of the 356 mammographic technologists included, 343 performed 889,347 SFM examinations, 51 performed 113,929 FFDM examinations, and 38 performed both SFM and FFDM examinations. A total of 4328 cancers were reported for SFM and 564 cancers for FFDM. The technologists had a statistically significant effect on the radiologists' recall rate, sensitivity, specificity, and CDR for both SFM and FFDM (P values <.01). For PPV1, variability by technologist was observed for SFM (P value <.0001) but not for FFDM (P value = .088).

CONCLUSIONS

The interpretative performance of radiologists in screening mammography varies substantially by the technologist performing the examination. Additional studies should aim to identify technologist characteristics that may explain this variation.

Preoperative MRI in patients with locoregional recurrent breast cancer: influence on treatment modalities

RATIONALE AND OBJECTIVES

The purpose of this analysis was to evaluate the impact of preoperative magnetic resonance imaging (MRI) on management in patients with locoregional recurrent breast cancer.

MATERIALS AND METHODS

Forty-three patients who underwent treatment for locoregional relapse of breast cancer from 2008 through 2012 were analyzed. All patients underwent both conventional surveillance by mammography, ultrasound, and clinical examination and subsequent bilateral breast MRI.

RESULTS

Preoperative MRI detected additional tumor foci in 15 of 43 patients (34.9%). In two cases (4.7%), the diagnosis of occult sites had no influence on the subsequent treatment. Two patients (4.7%) had an unfavorable change of surgical management with unnecessary additional resection of benign foci. Eleven patients benefited from the MRI scan detecting malignant occult lesions (25.6%) resulting in either additional surgical resection or radiotherapy. Patient and tumor characteristics in primary disease did not differ significantly between patients with a favorable impact on surgical management and patients who experienced either no benefit or even disadvantage from MRI scan.

CONCLUSIONS

Preoperative breast MRI has a strong impact on the management of locoregional recurrent breast cancer. This study demonstrates that breast MRI is a powerful supplement to conventional diagnostic work-up, both during follow-up or preoperative treatment planning in recurrent disease.