Ana P. Lourenco

ACR Appropriateness Criteria Breast Cancer Screening

Mammography is the recommended method for breast cancer screening of women in the general population. However, mammography alone does not perform as well as mammography plus supplemental screening in high-risk women. Therefore, supplemental screening with MRI or ultrasound is recommended in selected high-risk populations. Screening breast MRI is recommended in women at high risk for breast cancer on the basis of family history or genetic predisposition. Ultrasound is an option for those high-risk women who cannot undergo MRI. Recent literature also supports the use of breast MRI in some women of intermediate risk, and ultrasound may be an option for intermediate-risk women with dense breasts. There is insufficient evidence to support the use of other imaging modalities, such as thermography, breast-specific gamma imaging, positron emission mammography, and optical imaging, for breast cancer screening. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review includes an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Changes in Recall Type and Patient Treatment Following Implementation of Screening Digital Breast Tomosynthesis

PURPOSE To compare recall rate, types of abnormalities recalled, additional imaging required, biopsy positive predictive value (PPV), and cancer detection rate before and after implementation of screening digital breast tomosynthesis (DBT). MATERIALS AND METHODS This retrospective analysis was approved by the institutional review board and complied with HIPAA. The requirement to obtain informed consent was waived. Results from all screening digital mammography (DM) examinations performed without tomosynthesis from March 1, 2011, through February 29, 2012, and DBT examinations performed from March 1, 2012, through February 28, 2013, were reviewed to identify all Breast Imaging Reporting and Data System (BI-RADS) category 0 examinations (needs additional imaging). Radiology and pathology reports were reviewed. The recall rate, biopsy PPV, and cancer detection rate were calculated. Statistical analysis was performed by using a two-proportions z test. RESULTS The recall rate was 9.3% (1175 of 12 577 examinations; 95% confidence interval [CI]: 8.8%, 9.9%) for DM and 6.4% (827 of 12 921 examinations; 95% CI: 6.0%, 6.8%) for DBT, an overall reduction of 31% (P < .00001). The recall rate was lower with DM than with DBT for masses (8.9% vs 26.8%, respectively), distortions (0.6% vs 5.3%), and calcifications (13.4% vs 20.3%) (P < .0001 for all). The recall rate was lower with DBT than with DM for asymmetries (13.3% vs 32.2%, respectively) and focal asymmetries (18.2% vs 32.2%) (P < .0001 for both). Diagnostic evaluation with ultrasonography (US) increased with DBT at the time of additional imaging (2.6% for DM vs 28.3% for DBT, P < .0001). There was no significant difference between DM and DBT with regard to biopsy PPV (30.2% vs 23.8%, P = .21) or cancer detection rate per 1000 patients (5.4 vs 4.6, P = .44). CONCLUSION With DBT, the recall rate decreased and the biopsy PPV and cancer detection rate did not decrease. The distribution of recalled abnormalities changed, and more patients were evaluated with US only.

Stereotactic Breast Biopsy: Comparison of Histologic Underestimation Rates with 11- and 9-Gauge Vacuum- Assisted Breast Biopsy

OBJECTIVE The purpose of this study was to compare histologic underestimations at stereotactic 11- and 9-gauge vacuum-assisted breast biopsy. MATERIALS AND METHODS The reports of 1,223 consecutive stereotactic vacuum-assisted breast biopsies were retrospectively reviewed. An 11-gauge device was used to perform 828 and a 9-gauge device to perform 395 biopsies. The pathologic results were reviewed for all cases. Biopsy results of atypical ductal hyperplasia and ductal carcinoma in situ were compared with the pathologic results after surgical excision. Underestimation was defined as the need to upgrade atypical ductal hyperplasia to ductal carcinoma in situ or invasive carcinoma at surgery and to upgrade ductal carcinoma in situ to invasive carcinoma. Statistical significance was determined with the chi-square test and 95% CI. RESULTS In the 11-gauge group, 12 (26%) of 46 cases of atypical ductal hyperplasia were upgraded to ductal carcinoma in situ and one (2%) of the cases to invasive carcinoma. In the 9-gauge group, six (22%) of 27 cases of atypical ductal hyperplasia were upgraded to ductal carcinoma in situ and two (7%) of the cases to invasive carcinoma. In the 11-gauge group, 35 (28.7%) of 122 cases of ductal carcinoma in situ were upgraded to invasive carcinoma. In the 9-gauge group, 10 (23%) of 44 cases of ductal carcinoma in situ were upgraded to invasive carcinoma. CONCLUSION There was no statistically significant difference between 11-gauge biopsy and 9-gauge biopsy in underestimation of atypical ductal hyperplasia and ductal carcinoma in situ.

Ovarian and tubal torsion: imaging findings on US, CT, and MRI

Accurate diagnosis of adnexal torsion is often challenging, as clinical presentation is nonspecific and the differential for pelvic pain is broad. However, prompt diagnosis and treatment is critical to good clinical outcomes and preservation of the ovary and/or fallopian tube. Ultrasound (US) imaging is most frequently used to assess torsion. However, as computed tomography (CT) utilization in the emergency setting has increased, there are times when CT is the initial imaging test. Additionally, the nonspecific clinical presentation may initially be interpreted as gastrointestinal in etiology, where CT is the preferred exam. For these reasons, it is imperative to know the findings of adnexal torsion on CT as well as US. Magnetic resonance imaging (MRI) is helpful in cases where the diagnosis remains unclear and is particularly helpful in the young or pregnant patient with equivocal sonographic findings, as it provides excellent soft tissue contrast without ionizing radiation. This article will illustrate the findings of surgically confirmed ovarian and fallopian tube torsion on US, CT, and MRI, including those in the pregnant patient. Ovarian enlargement, adnexal mass, twisting of the vascular pedicle, edematous and heterogeneous appearance of the ovary, peripheral ovarian follicles, free fluid, uterine deviation towards the side of torsion, adnexal fat stranding, tubal dilatation, and decreased adnexal enhancement will be reviewed. Familiarity with the range of imaging findings across multiple modalities is key to improving the likelihood of timely diagnosis and therefore improved clinical outcomes.

High-Risk Lesions at MRI-Guided Breast Biopsy: Frequency and Rate of Underestimation

OBJECTIVE The purpose of this article is to determine the underestimation rate of high-risk lesions diagnosed at MRI-guided breast biopsy. MATERIALS AND METHODS This was a retrospective review of 446 MRI-guided breast biopsies from January 2006 through December 2010. Data were collected on examination indication, lesion size and type, and pathology results. Biopsies were performed with a 9-gauge vacuum-assisted device. Biopsy results of atypical ductal hyperplasia (ADH), papillary lesion, radial scar, lobular neoplasia, and atypia were identified and compared with final excisional pathology results. Underestimation rates were calculated and data were compared by patient and lesion characteristics using chi-square analysis. RESULTS Of the 446 MRI-guided biopsies, 96 (21.5%) were high-risk lesions. Forty-two of 96 lesions (44%) were masses, and 54 (56%) showed nonmass enhancement. Twenty of 96 lesions (20.8%) were ADH, nine (9.4%) were lobular neoplasia, 27 (28.1%) were papillary lesions, 20 (20.8%) were radial scar, and 20 (20.8%) were other atypias. Sixty-nine of 96 lesions (71.9%) had surgical excisional pathology results available. Sixteen of 69 (23.2%) lesions were upgraded to malignancy; 11 of the 16 (68.8%) were upgraded to ductal carcinoma in situ (DCIS) and five (31.2%) were upgraded to invasive carcinoma. The underestimation rate was 31.6% (6/19) for ADH, 5.9% (1/17) for papillary lesions, 23.1% (3/13) for radial scar, 28.6% (2/7) for lobular neoplasia, and 30.8% (4/13) for other atypias (p = 0.43). There was no statistically significant difference in underestimation rate by lesion type, size, or history of newly diagnosed breast cancer. CONCLUSION MRI-guided breast biopsy yielded high-risk lesions in 21.5% of cases, and the underestimation rate was 23.2%. No patient or lesion characteristics correlated with underestimation rate.

Ovarian torsion: Case–control study comparing the sensitivity and specificity of ultrasonography and computed tomography for diagnosis in the emergency department

OBJECTIVE Evaluate the sensitivity and specificity of pelvic ultrasound (US) and abdominopelvic computed tomography (CT) for the identification of ovarian torsion in women presenting to the emergency department with acute lower abdominal or pelvic pain. MATERIALS AND METHODS This is a retrospective study of 20 cases of ovarian torsion and 20 control patients, all of whom had both US and CT performed in the emergency department. Two radiologists who were blinded to clinical data interpreted all studies as (1) demonstrating an abnormal ovary or not, and (2) suggestive of torsion or not. Sensitivity, specificity and interobserver variation were calculated for each imaging modality. RESULTS Pelvic US was interpreted as demonstrating an abnormal ovary in 90.0% of ovarian torsion cases by reader 1, and in 100.0% by reader 2, whereas CT was interpreted as revealing an abnormal ovary in 100.0% of torsion cases by both readers. Pelvic US for ovarian torsion was 80.0% sensitive (95% CI, 58.4-91.9%) and 95.0% specific (95% CI, 76.4-99.1%) for reader 1, while 80.0% sensitive (95% CI, 58.4-91.9%) and 85.0% specific (95% CI, 64.0-95.0%) for reader 2. Interobserver agreement for pelvic US was fair (Kappa=0.60). Abdominopelvic CT for ovarian torsion was 100.0% sensitive (95% CI, 83.9-100.0%) and 85.0% specific (95% CI, 64.0-94.5%) for reader 1, while 90.0% sensitive (95% CI, 69.9-97.2%) and 90.0% specific (95% CI, 69.9-97.2%) for reader 2. Interobserver agreement was excellent (Kappa=0.85). CONCLUSION The diagnostic performance of CT is not shown to be significantly different from that of US in identifying ovarian torsion in this study. These results suggest that when CT demonstrates findings of ovarian torsion, the performance of another imaging exam (i.e. US) that delays therapy is unlikely to improve preoperative diagnostic yield.

Improving outcomes of screening breast MRI with practice evolution: Initial clinical experience with 3T compared to 1.5T

To determine if changing from 1.5T to 3T breast magnetic resonance imaging (MRI) is associated with a change in BI‐RADS categories, positive predictive value of biopsy recommendation, or cancer detection rates in high‐risk screening breast MRI.

DOES 16-DETECTOR COMPUTED TOMOGRAPHY IMPROVE DETECTION OF NON-TRAUMATIC SUBARACHNOID HEMORRHAGE IN THE EMERGENCY DEPARTMENT?

The diagnosis of subarachnoid hemorrhage remains difficult to establish, yet the sensitivity of increasingly available 16-detector computed tomography (CT) has not been evaluated. The objective of this study was to estimate the sensitivity of 16-detector CT for the diagnosis of non-traumatic subarachnoid hemorrhage in the Emergency Department (ED). A retrospective review was performed in an academic tertiary care hospital. Patients presenting to the ED from September 2003 through December 2004 with symptoms suggestive of subarachnoid hemorrhage and having a final diagnosis of non-traumatic subarachnoid hemorrhage were eligible for study. Diagnosis was established by positive 16-detector CT examination of the brain, or spinal fluid analysis. Patient demographics and results of CT, angiogram, and spinal fluid analysis were reviewed. Sensitivity of 16-detector CT was calculated by comparing CT results and cerebral angiogram results. Refined Wilson Simple Asymptotic 95% confidence intervals were calculated. Sixty-one consecutive patients met the study criteria and had a final diagnosis of non-traumatic subarachnoid hemorrhage. One of these patients did not have subarachnoid hemorrhage identified by 16-detector CT, but had a positive lumbar puncture and an aneurysm confirmed on cerebral angiography. Sensitivity of 16-detector CT for subarachnoid hemorrhage was 97% (95% confidence interval 84-100%). Sixteen-detector CT did not improve detection of non-traumatic subarachnoid hemorrhage when compared with studies using single-detector CT. If there is high clinical suspicion for non-traumatic subarachnoid hemorrhage and non-contrast 16-detector CT scan is negative, further evaluation is suggested.

Probably benign breast MRI lesions: frequency, lesion type, and rate of malignancy.

To determine the frequency, malignancy rate, and imaging characteristics of BI‐RADS (Breast Imaging Reporting and Data System) 3 MRI detected lesions.

Original articleACR Appropriateness Criteria Breast Cancer Screening

Mammography is the recommended method for breast cancer screening of women in the general population. However, mammography alone does not perform as well as mammography plus supplemental screening in high-risk women. Therefore, supplemental screening with MRI or ultrasound is recommended in selected high-risk populations. Screening breast MRI is recommended in women at high risk for breast cancer on the basis of family history or genetic predisposition. Ultrasound is an option for those high-risk women who cannot undergo MRI. Recent literature also supports the use of breast MRI in some women of intermediate risk, and ultrasound may be an option for intermediate-risk women with dense breasts. There is insufficient evidence to support the use of other imaging modalities, such as thermography, breast-specific gamma imaging, positron emission mammography, and optical imaging, for breast cancer screening. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review includes an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.