Elsa Arribas

Invasive micropapillary carcinoma of the breast: mammographic, sonographic, and MRI features.

OBJECTIVE The purpose of this study was to describe the clinical, imaging, and histopathologic findings of invasive micropapillary carcinoma of the breast. CONCLUSION The imaging characteristics of invasive micropapillary carcinoma are highly suggestive of malignancy. The lesion is a high-density irregular mass with indistinct margins associated with microcalcifications on mammograms; a solid irregular hypoechoic mass with indistinct margins and frequent axillary nodal involvement on sonograms; and a multifocal mass on MR images. This tumor may necessitate aggressive management.

Clinical and Radiologic Data and Core Needle Biopsy Findings Should Dictate Management of Cellular Fibroepithelial Tumors of the Breast

Abstract:  Fibroepithelial lesions with cellular stroma identified on core needle biopsy (CNB) may prove to be either fibroadenoma or phyllodes tumor at excision; therefore, management of these rare lesions is highly controversial. We aim to assess the management and the outcome of 101 cellular fibroepithelial lesions diagnosed on CNB over a 6‐year period in one institution. Consensus on clinical management in each individual patient was reached during multi‐disciplinary conferences, based on careful correlation of clinical data with results of imaging studies and pathology of CNB samples. Radiologic findings (mammogram and sonogram) and multiple histologic parameters on CNB specimen were blindly re‐evaluated by one experienced breast radiologist and two breast pathologists, respectively, and results were correlated with final diagnosis at excision. Cellular fibroepithelial lesions with indeterminate or suspect imaging findings, with larger size, and with an equivocal comment such as “cannot rule out phyllodes tumor” in the pathology report were excised more frequently (p = 0.05, p = 0.034, and p = 0.01, respectively). Of 43 excised lesions, 13 were classified as benign phyllodes tumors, 23 as fibroadenoma and seven as benign cellular fibroepithelial lesion. The final diagnosis at excision did not significantly correlate with any clinical data, or with retrospective evaluation of imaging findings or comprehensive evaluation of multiple histologic parameters. In 58 patients who had clinical and radiologic follow‐up (mean ± SD: 30 ± 21 months) there was no evidence of disease progression. No clinical and radiologic findings and/or comprehensive evaluation of multiple histologic parameters on CNB specimen are distinctive enough to predict final classification of equivocal cellular fibroepithelial lesions. However, careful clinico‐pathologic and radiologic correlation may help to select the most clinically significant lesions for proper immediate surgical management. Follow‐up alone may be an appropriate alternative for a subset of patients, given a good clinical, pathologic, and radiologic correlation.

Investigating the limit of detectability of a positron emission mammography device: a phantom study.

PURPOSE A new positron emission mammography (PEM) device (PEM Flex Solo II, Naviscan Inc., San Diego, CA) has recently been introduced and its performance characteristics have been documented. However, no systematic assessment of its limit of detectability has been evaluated. The aim of this work is to investigate the limit of detectability of this new PEM system using a novel, customized breast phantom. METHODS Two sets of F-18 infused gelatin breast phantoms of varying thicknesses (2, 4, 6, and 8 cm) were constructed with and without (blank) small, shell-less contrast objects (2 mm thick disks) of varying diameters (3-14.5 mm) [volumes: 0.15-3.3 cc] and activity concentration to background ratio (ACR) (2.7-58). For the phantom set with contrast objects, the disks were placed centrally inside the phantoms and both phantom sets were imaged for a period of 10 min on the PEM device. In addition, scans for the 2 and 6 cm phantoms were repeated at different times (0, 90, and 150 min) post phantom construction to evaluate the impact of total activity concentration (count density) on lesion detectability. Each object from each phantom scan was then segmented and placed randomly in a corresponding blank phantom image. The resulting individual images were presented blindly to seven physician observers (two nuclear medicine and five breast imaging radiologists) and scored in a binary fashion (1-correctly identified object, 0-incorrect). The sensitivity, specificity, and accuracy of lesion detectability were calculated and plots of sensitivity versus ACR and lesion diameters for different phantom thicknesses and count density were generated. RESULTS The overall (mean) detection sensitivity across all variables was 0.68 (95% CI: [0.64, 0.72]) with a corresponding specificity of 0.93 [0.87, 0.98], and diagnostic accuracy of 0.72 [0.70, 0.75]. The smallest detectable object varied strongly as a function of ACR, as sensitivity ranged from 0.36 [0.29, 0.44] for the smallest lesion size (3 mm) to 0.80 [0.75, 0.84] for the largest (14.5 mm). CONCLUSIONS The detectability performance of this PEM system demonstrated its ability to resolve small objects with low activity concentration ratios which may assist in the identification of early stage breast cancer. The results of this investigation can be used to correlate lesion detectability with tumor size, ACR, count rate, and breast thickness.

Visibility of simulated microcalcifications--A hardcopy-based comparison of three mammographic systems

Full-field digital mammography systems are currently available for clinical use. These digital systems offer improved image quality, flexible image processing, display, storage, retrieval, and transmission. These systems employ a variety of different x-ray detectors based on storage phosphors (in computed radiography), charge-coupled devices (CCDs), or amorphous silicon flat panels (FPs). The objective of this study is to compare three different types of mammographic detectors: screenfilm (SF) combination, a CsI-based FP detector, a CCD and x-ray phosphor-based detector for their performance in detection of simulated microcalcifications. Microcalcifications (MCs) were simulated with calcium carbonate grains of various sizes (90-355 microm). They were overlapped with a slab of simulated 50% adipose/50% glandular breast tissue for a uniform background or an anthropomorphic breast phantom for a tissue structure background. Images of the phantoms, acquired with and without magnification, were reviewed by mammographers, physicists, and students. A five-point confidence level rating was given for each MC reviewed. Average ratings from the mammographers were used to compare the performances of the three imaging systems, various MC size groups, and two magnification modes. The results indicate that with uniform background and no magnification, the FP system performed the best while the SF system did slightly better than the CCD system. With magnification added, all detection tasks were improved except for the smallest and largest one or two size groups. In particular, detection in the SF and CCD images was significantly improved over that in the FP images. With tissue structure background and no magnification, the FP system was outperformed by the SF and the CCD systems. With magnification added, the performance of the FP and the CCD systems was improved significantly. With this improvement, the SF and FP systems were outperformed by the CCD system.

A Clinical Feasibility Trial for Identification of Exceptional Responders in Whom Breast Cancer Surgery Can Be Eliminated Following Neoadjuvant Systemic Therapy

Objective: To determine the accuracy of fine-needle aspiration (FNA) and vacuum-assisted core biopsy (VACB) in assessing the presence of residual cancer in the breast after neoadjuvant systemic therapy (NST). Summary Background Data: Pathologic complete response (pCR) rates after NST have improved dramatically, suggesting that surgery might be avoided in some patients. Safe avoidance of surgery would require accurate confirmation of no residual invasive/in situ carcinoma. Methods: Forty patients with T1-3N0-3 triple-negative or HER2-positive cancer receiving NST were enrolled in this single-center prospective trial. Patients underwent ultrasound-guided or mammography-guided FNA and VACB of the initial breast tumor region before surgery. Findings were compared with findings on pathologic evaluation of surgical specimens to determine the performance of biopsy in predicting residual breast disease after NST. Results: Median initial clinical tumor size was 3.3 cm (range, 1.2–7.0 cm); 16 patients (40%) had biopsy-proven nodal metastases. After NST, median clinical tumor size was 1.1 cm (range, 0–4.2 cm). Nineteen patients (47.5%) had a breast pCR and were concordant with pathologic nodal status in 97.5%. Combined FNA/VACB demonstrated an accuracy of 98% (95% CI, 87%–100%), false-negative rate of 5% (95% CI, 0%–24%), and negative predictive value of 95% (95% CI, 75%–100%) in predicting residual breast cancer. VACB alone was more accurate than FNA alone (P = 0.011). Conclusions: After NST, image-guided FNA/VACB can accurately identify patients with a breast pCR. Based on these results, a prospective clinical trial has commenced in which breast surgery is omitted in patients with a breast pCR after NST according to image-guided biopsy.

Conspicuity of Microcalcifications on Digital Screening Mammograms Using Varying Degrees of Monitor Zooming

RATIONALE AND OBJECTIVES American College of Radiology guidelines suggest that digital screening mammographic images should be viewed at the full resolution at which they were acquired. This slows interpretation speed. The aim of this study was to examine the effect of various levels of zooming on the detection and conspicuity of microcalcifications. MATERIALS AND METHODS Six radiologists viewed 40 mammographic images five times in different random orders using five different levels of zooming: full resolution (100%) and 30%, 61%, 88%, and 126% of that size. Thirty-three images contained microcalcifications varying in subtlety, all associated with breast cancer. The clusters were circled. Seven images contained no malignant calcifications but also had randomly placed circles. The radiologists graded the presence or absence and visual conspicuity of any calcifications compared to calcifications in a reference image. They also counted the microcalcifications. RESULTS The radiologists saw the microcalcifications in 94% of the images at 30% size and in either 99% or 100% of the other tested levels of zooming. Conspicuity ratings were worst for the 30% size and fairly similar for the others. Using the 30% size, two radiologists failed to see the microcalcifications on either the craniocaudal or mediolateral oblique view taken from one patient. Interobserver agreement regarding the number of calcifications was lowest for the 30% images and second lowest for the 100% images. CONCLUSIONS Images at 30% size should not be relied on alone for systematic scanning for microcalcifications. The other four levels of magnification all performed well enough to warrant further testing.

Comparison of slot scanning digital mammography system with full-field digital mammography system

The purpose of this study was to evaluate and compare microcalcification detectability of two commercial full-field digital mammography (DM) systems. The first unit was a flat panel based DM system (FFDM) which employed an anti-scatter grid method to reject scatter, and the second unit was a charge-coupled device-based DM system (SSDM) which used scanning slot imaging geometry to reduce scatter radiation. Both systems have comparable scatter-to-primary ratios. In this study, 125-160 and 200-250 microm calcium carbonate grains were used to simulate microcalcifications and imaged by both DM systems. The calcium carbonate grains were overlapped with a 5-cm-thick 50% adipose/50% glandular simulated breast tissue slab and an anthropomorphic breast phantom (RMI 165, Gammex) for imaging at two different mean glandular dose levels: 0.87 and 1.74 mGy. A reading study was conducted with seven board certified mammographers with images displayed on review workstations. A five-point confidence level rating was used to score each detection task. Receiver operating characteristic (ROC) analysis was performed and the area under the ROC curve (A(z)) was used to quantify and compare the performances of these two systems. The results showed that with the simulated breast tissue slab (uniform background), the SSDM system resulted in higher A(z)s than the FFDM system at both MGD levels with the difference statistically significant at 0.87 mGy only. With the anthropomorphic breast phantom (tissue structure background), the SSDM system performed better than the FFDM system at 0.87 mGy but worse at 1.74 mGy. However, the differences were not found to be statistically significant.

Detection of Microcalcifications on Digital Screening Mammograms Using Varying Degrees of Monitor Zooming

OBJECTIVE The American College of Radiology recommends that mammogram images be viewed at 100% resolution (also called one-to-one or full resolution). We tested the effect of this and three other levels of zooming on the ability of radiologists to identify malignant calcifications on screening mammographic views. MATERIALS AND METHODS Seven breast imagers viewed 77 mammographic images, 32 with and 45 without malignant microcalcifications, using four different degrees of monitor zooming. The readers indicated whether they thought a cluster of potentially malignant calcifications was present and where the cluster was located. Tested degrees of zooming included fit screen, a size midway between fit screen and 100%, 100%, and a size slightly larger than 100%. RESULTS Readers failed to detect 17 clusters of malignant calcifications with fit-screen images, 12 clusters with midway images, 13 clusters with 100% images, and 11 clusters with slightly larger images. When viewing images without malignant microcalcifications, the readers marked false-positive areas on 25 images using fit-screen images, 43 of the midway images, 40 of the 100% images, and 29 of the slightly larger images. CONCLUSION All four tested levels of zooming functioned well. There was a trend for the fit-screen images to function slightly less well than the others with regard to sensitivity, so it may not be prudent to rely on those images without other levels of zooming. The 100% resolution images did not function noticeably better than the others.

Mammographic-sonographic correlation.

The traditional role for ultrasound in breast imaging has been as an adjunct to mammography, with an emphasis on differentiating cysts from solid masses. The use of breast sonography has expanded over the past decade to include screening for malignancy, characterization of benign and malignant masses, local-regional staging, and monitoring response to neoadjuvant chemotherapy. In addition, ultrasound has realtime capability, making sonography the preferred modality for guiding interventional procedures. 1 When sonography is used to further evaluate mammographic findings, accurate mammographic‐sonographic correlation is required. In this article, we focus on sonographic evaluation of various breast abnormalities, with an emphasis on mammographic‐sonographic correlation.

A desktop Digital Imaging and Communications in Medicine picture archiving and communications system with multiple monitors using Windows ’98

ConclusionCombining DICOM software and internet access using desktops, an accessible and low-cost PACS system is conveniently available to the medical community.