Mammographic and histologic correlations of microcalcifications

The majority of microcalcifications found on mammograms are associated with benign disease; however, some types accompany malignant disease. By correlating histologic with mammographic findings, the radiologist may gain an understanding of the morphologic characteristics and distribution of microcalcifications. We present radiologic and histologic images from a series of cases of nonpalpable, clustered microcalcifications. Such microcalcifications can be divided into two basic histologic groups: lobular and ductal. Although rounded, similarly shaped lobular calcifications can be differentiated mammographically from ductal calcifications with their irregular margins and varying size and shape, both types can be associated with benign and malignant processes. Biopsy is usually needed to confirm the diagnosis when clustered microcalcifications are found at mammography.     

Breast US in patients who had microcalcifications with low concern of malignancy on screening mammography

PURPOSE: To review ultrasound (US) findings in patients who have suspicious microcalcifications with low concern of malignancy (BI-RADS category 4A) on screening mammography and to evaluate helpful findings in differentiating benign and malignant lesions. MATERIALS AND METHODS: Between August 2005 and July 2006, 192 patients showed microcalcifications only, without mass or associated density, on screening mammography. Among them, we selected 82 patients who had microcalcifications with low concern of malignancy (category 4A) that were pathologically confirmed by surgical excision after wire localization (n=23) or biopsy (n=59). Breast US was performed in 37/82 cases and we analyzed the US findings for the calcification areas in these patients, evaluating the findings with benign or malignant pathological results. We correlated US findings with mammographic calcifications using mammography-guided 2D-localization for the calcifications before US examination. RESULTS: There were 12 malignant lesions (32.4%) including 3 invasive ductal carcinomas (IDC), one microinvasive ductal carcinoma (MIDC), 8 ductal carcinoma in situ (DCIS) and 25 benign lesions (67.6%) including 2 atypical ductal hyperplasias (ADH). IDC showed calcifications within heterogeneous hypoechoic parenchyma or calcifications within complex hypoechoic masses of taller-than-wide shape on US. One MIDC showed calcifications within heterogeneous hypoechoic parenchyma and six DCIS showed negative findings, or calcifications with a small nodule, or only calcifications on US. The most common positive US finding in benign lesions was cysts with calcifications. In 24/37 cases (64.8%) with negative US findings, 18 (75%) were benign lesions and 6 (25%) were DCIS. CONCLUSION: In patients with category 4A microcalcifications without associated findings on screening mammography, negative US findings had a high rate of benign results (18/24, 75%). Visible calcifications within heterogeneous hypoechoic parenchyma or mass on US increased the probability of malignancy.     

Lobular carcinoma in situ: mammographic-pathologic correlation of results of needle-directed biopsy

The mammographic and histologic findings were reviewed in 41 consecutive cases of isolated lobular carcinoma in situ (LCIS) unassociated with any malignant diagnosis. Thirty-one needle-directed breast biopsies were performed to evaluate clustered microcalcifications. In 24 of the 31 cases, the calcifications were found in areas of benign breast disease, with LCIS representing a separate process. In the few cases in which microcalcifications were seen in association with LCIS, a greater number of similar calcifications were present in adjacent benign disease. Soft-tissue abnormalities necessitating the performance of a biopsy represented benign foci, except in one patient with LCIS in and adjacent to a fibroadenoma. The authors conclude that LCIS has no characteristic mammographic features. LCIS is detected as an incidental finding at breast biopsy, with the mammographic abnormality predominantly reflecting a benign process.     

The relationship of mammographic microcalcification to histologic malignancy: radiologic-pathologic correlation

Forty consecutive cases of nonpalpable breast carcinoma presenting on the mammogram as microcalcifications without an associated mass were reviewed. The precise relationship between the mammographic microcalcification and the histologic carcinoma was determined in each case. In 25 cases (63%), the mammographic calcium was confined to the tumor, and in 13 cases (33%), the calcification was present both within the tumor and contiguous to the tumor margin. In two cases (5%), the calcium was not contained within the tumor but was located next to it. In one of these cases, the calcium was within 4 mm of the malignant neoplasm and in the other it was within 13 mm. No difference was seen between the appearance of the calcifications located within the tumor and the appearance of calcification next to the tumor. Precise histologic analysis revealed that microcalcifications that had prompted biopsy were confined to the tumor in 63%, within and contiguous to the tumor in 32%, and within 13 mm of the tumor in 5%.     

US of mammographically detected clustered microcalcifications

PURPOSE: To determine whether ultrasonography (US) can depict breast masses associated with mammographically detected clustered microcalcifications and whether the visibility at US is different between benign and malignant lesions. MATERIALS AND METHODS: Ninety-four patients with 100 mammographically detected microcalcification clusters prospectively underwent US with a 10- or 12-MHz transducer before mammographically guided presurgical hook-wire localization. The visibility of breast masses at US was correlated with histologic and mammographic findings. RESULTS: Surgical biopsy revealed 62 benign lesions, 30 intraductal cancers, and eight invasive cancers. At US, breast masses associated with microcalcifications were seen in 45 (45%) of 100 cases. US depicted more breast masses associated with malignant (31 [82%] of 38) than with benign (14 [23%] of 62) microcalcifications (P: <.001). In malignant microcalcification clusters larger than 10 mm, US depicted associated breast masses in all 25 cases. There was no statistically significant difference in shape and distribution of calcific particles, as well as in breast composition, at mammography between US visible and invisible groups. CONCLUSION: Given a known mammographic location, US with a high-frequency transducer can depict breast masses associated with malignant microcalcifications, particularly clusters larger than 10 mm. US can be used to visualize large clusters of microcalcifications that have a very high suspicion of malignancy.     

Quiz. Primary breast amyloidosis

Primary breast amyloidosis is rare, usually manifestating as suspicious masses in mammography, with or without associated microcalcifications. The final diagnosis is based on fine needle aspiration cytology or biopsy yielding clumps of amorphous material surrounded by lymphocytes and giant cells that characterize this entity. In our case the only mammographic finding was that of clustered, suspicious microcalcifications without any associated mass.     

DIMA enlargement mammography in microcalcifications: a prospective study with ROC analysis

The purpose of this study was to investigate whether the four-fold magnification mammography (direct magnification, DIMA) technique would perform better than conventional 1.5-fold magnification mammography in the differentiation of breast microcalcifications into benign and malignant. Fifty patients with non-palpable microcalcifications detected by mammography were examined immediately prior to surgical biopsy using both a conventional (1.5-fold) and the DIMA (fourfold) magnification mammography techniques. The microcalcifications were classified by five experienced radiologists using morphological criteria. A receiver operating characteristics curve (ROC) analysis of the sensitivity and specificity of both techniques in assessing malignancy was then carried out. The DIMA mammography technique was slightly but non-significantly superior to the conventional method in detecting malignancy (p > 0.05). Coarse granular and pleomorphic calcifications were detected more frequently with the DIMA technique. Coarse calcifications were significantly more frequently associated with histologically benign findings, whereas fine granular calcifications were significantly more likely to be malignant lesions. Assessment of malignancy associated with microcalcifications using morphological criteria is not significantly improved by mammography techniques with higher magnification.     

New bilateral microcalcifications at mammography in a postlactational woman: case report

A 33-year-old woman with a strong family history of breast cancer who was referred for mammography 5 weeks after completing lactation was found to have new diffuse bilateral microcalcifications in the breast ducts. Contrast material-enhanced magnetic resonance imaging of the breast showed bilateral patchy areas of abnormal enhancement. Large-core needle biopsy showed diffuse calcifications within expanded benign ducts in a background of lactational change, without evidence of malignancy. To the authors' knowledge, these calcifications have not been previously reported and are possibly related to milk stasis or apoptosis associated with lactation.     

Sensitivity of a Direct Computer-aided Detection System in Full-field Digital Mammography for Detection of Microcalcifications Not Associated with Mass or Architectural Distortion

Purpose

The purpose of this study was to evaluate the sensitivity of a direct computer-aided detection (CAD) system (d-CAD) in full-field digital mammography (FFDM) for the detection of microcalcifications not associated with mass or architectural distortion.

Materials and Methods

A database search of 1063 consecutive stereotactic core biopsies performed between 2002 and 2005 identified 196 patients with Breast Imaging-Reporting and Data System (BI-RADS) 4 and 5 microcalcifications not associated with mass or distortion detected exclusively by bilateral FFDM. A commercially available CAD system (Second Look, version 7.2) was retrospectively applied to the craniocaudal and mediolateral oblique views in these patients (mean age, 59 years; range, 35–84 years). Breast density, location and mammographic size of the lesion, distribution, and tumour histology were recorded and analysed by using χ², Fisher exact, or McNemar tests, when applicable.

Results

When using d-CAD, 71 of 74 malignant microcalcification cases (96%) and 101 of 122 benign microcalcifications (83%) were identified. There was a significant difference (P < .05) between CAD sensitivity on the craniocaudal view, 91% (68 of 75), vs CAD sensitivity on the mediolateral oblique view, 80% (60 of 75). The d-CAD sensitivity for dense breast tissue (American College of Radiology [ACR] density 3 and 4) was higher (97%) than d-CAD sensitivity (95%) for nondense tissue (ACR density 1 and 2), but the difference was not statically significant. All 28 malignant calcifications larger than 10 mm were detected by CAD, whereas the sensitivity for lesions small than or equal to 10 mm was 94%.

Conclusions

D-CAD had a high sensitivity in the depiction of asymptomatic breast cancers, which were seen as microcalcifications on FFDM screening, with a sensitivity of d-CAD on the craniocaudal view being significantly better. All malignant microcalcifications larger than 10 mm were detected by d-CAD.     

Differentiation of benign and malignant local tumor recurrence after lumpectomy

During a 5-year period, 28 women who had been treated conservatively for breast carcinoma had 29 reexcisions of the lumpectomy site because of suspicion of a recurrent malignant tumor. Biopsy results were benign in 19 cases and malignant in 10 cases. Sixteen of the 19 benign tumors had developed within 2 years after therapy. In 16 benign cases, a palpable lump developed at the scar and was found on biopsy to be fat necrosis or fibrosis. Seven of these cases had normal mammographic findings. Three women with abnormal mammographic findings but a normal breast examination had punctate microcalcifications develop at the scar; these were due to fibrosis in two and sclerosing adenosis in the other. Of the 10 malignant recurrent tumors, seven were palpable, four of which also were identifiable by mammography. Of seven mammographically identifiable recurrent tumors at the surgical site, four were palpable. Mammographic findings were a single mass in two cases, multiple masses in one, microcalcification in three, and a mass with microcalcifications in one. Malignant microcalcifications were all linear, irregular, and in one case branching. Mean time to recurrence in these 10 women was 3 years. This experience suggests that benign disease usually occurs at the scar within 2 years after the original therapy and when palpable may not show changes on mammography. When microcalcifications do occur, they are usually punctate.     

Computer-aided preoperative diagnosis of microcalcifications on mammograms

PURPOSE: To evaluate of a computer-aided method for differentiating malignant from benign clustered microcalcifications. MATERIAL AND METHODS: Our material was 350 suspicious microcalcifications on mammograms from 330 female patients who underwent breast biopsy (after hook wire localization and under mammographic guidance). The histologic findings were malignant in 140 cases (40%) and benign in 210 cases (60%). Those clusters were manually detected, computer-aided analyzed and quantitatively estimated. Besides computer analysis, 3 physicians-observers (2 radiologists and 1 breast surgeon) evaluated the malignant or benign nature of the clustered microcalcifications. The performance of the artificial network, each observer and the three observers as a group was evaluated by receiver operating characteristics (ROC) curves. RESULTS: Comparison of the ROC curves revealed the following AUC values (area under the curve): computer - 0.950, physician 1 - 0.815, physician 2 - 0.830, physician 3 - 0.830, and physicians as a group - 0.825. The results, compared by the student t-test for paired data, showed a statistically significant difference between computer analysis and physicians' performance, independently and as a group. CONCLUSION: Our study showed that computer analysis achieved statistically significantly better performance than that of physicians in the classification of malignant and benign calcifications.     

Mammographic control after quadrantectomy and radiation therapy]

The efficacy of combined surgery and radiation therapy in the treatment of breast cancer has increased the use of mammography in the follow-up to detect early recurrences. The authors report their experience in the follow-up of 43 breast cancers after treatment with local excision, axillary dissection, and irradiation. Mammography was performed at 6.12, and 24 months. The radiological findings were: 38/43 (88.3%) breasts with abnormal mammographic patterns, skin thickening in 36/43 (83.7%) cases, breast retraction in 16/43 (37.2%), architectural distortion in 17/43 (39.5%), increased parenchymal density in 33/43 (76.7%), calcifications in 6/43 (13.9%), and a mass in 10/43 (23.2%) cases. The authors describe histologic changes, corresponding to mammographic findings, and evolution of the treated breasts. Suspicious findings were microcalcifications in one case and a mass in 6 cases (4 of them at 6 months and 2 at 12). Excisional biopsy, performed in the above 7 patients, confirmed recurrence in 4 cases. In 3 cases with negative pathology, where the malignant nature of the lesion could not be demonstrated, we observed: a cluster of microcalcifications undistinguishable from neoplasm in 1 case and spiculated nodules with architectural distortion in the extant 2 cases. Further limitations of mammography were due to radiological density of the breast in one case, and to its minimal size in another--these elements delayed both correct interpretation of mammographic findings and final diagnosis. The low agreement between mammography and histology proved the difficulty of both analysis and evaluation of abnormal post-irradiation breast tissue. The authors, in agreement with literature reports, suggest the schedule for clinical and mammographic follow-up.     

Report on the 89th Scientific Assembly and Annual Meeting of the Radiological Society of North America--micro-focus x-ray CT imaging of breast specimens with microcalcifications

LEARNING OBJECTIVES: (1)Understand images of breast specimens with microcalcifications obtained by use of micro-focus CT. (2)Learn the relationship between mammographic features, pathologic characteristics, and micro-focus CT images. (3)Learn the usefulness of three-dimensional images in understanding of detailed structures and patterns of microcalcifications without cutting the specimen. ABSTRACT: Microcalcifications are one of the important sign for early detection of breast cancer by use of mammography, and has resulted in the detection of nonpalpable cancer. However, it is difficult to distinguish between benign and malignant microcalcifications, thus causing high false-positive rate. Micro-focus CT employs a x-ray tube of a focal spot size less than 10 microns, and has high spatial resolution, thus resulting in more accurate visualization of structures of microcalcifications. We investigated the relationship between micro-focus CT images of breast specimens with microcalcifications, mammographic features and pathologic characteristics. Micro-focus CT imaging was comparable to pathologic images in terms of resolution and contrast. Microcalcifications were more clearly detected in micro-focus CT imaging than specimen radiographs. Three-dimensional imaging on microcalcifications provided a tool for studying the shape and distribution of calcifications. Micro-focus CT for breast imaging was very useful for understanding of structures and patterns of microcalcifications without cutting the specimen.     

When have mammographic calcifications been adequately sampled at needle core biopsy?

AIMS: To determine if the number of flecks of calcification retrieved at stereotaxic core needle biopsy or the number of core samples obtained containing calcification are related to biopsy sensitivity, and to determine how many calcifications or cores containing calcification the radiologist should aim to retrieve when sampling mammographic microcalcification. MATERIALS AND METHODS: A retrospective review was performed of core specimen radiographs from 57 consecutive patients who had stereotaxic core needle biopsies of impalpable malignant microcalcifications without an associated mammographic mass. The total number of calcifications retrieved and the numbers of cores containing calcification were correlated with findings at core and surgical histology. RESULTS: Increasing retrieval of calcification elements visible on specimen radiography was associated with increasing sensitivity of the biopsy. Five or more flecks of calcium gave an absolute sensitivity of 100%. Increasing numbers of core samples obtained containing radiographically demonstrable calcification was also associated with increasing sensitivity. Three or more cores containing calcium resulted in a 100% absolute sensitivity for malignancy. CONCLUSION: To ensure adequate sampling of calcification at core biopsy, an optimum of either three or more cores containing calcium or five or more flecks of calcium in total is required. Achieving this target ensures a high pre-operative diagnosis rate for malignant microcalcifications.Bagnall, M. J. C. (2000). Clinical Radiology 55, 548-553.     

Computer-aided detection in digital mammography: comparison of craniocaudal, mediolateral oblique, and mediolateral views

PURPOSE: To retrospectively compare the sensitivity of a computer-aided detection (CAD) system for depicting breast cancer in three digital mammographic views. MATERIALS AND METHODS: This study was conducted with institutional review board approval; informed consent was waived. A commercially available CAD system was applied to the craniocaudal, mediolateral oblique, and mediolateral digital mammographic views of 83 women (mean age, 48 years; range, 30-66 years) with 83 histologically proved breast cancers. Findings were 59 masses and 41 microcalcifications (17 lesions showed both findings; 42 lesions, mass only; and 24 lesions, microcalcification only). The paired t test was used to analyze sensitivity of the CAD system for the detection of cancer in these three mammographic views and in combinations of the views. RESULTS: The sensitivities of the CAD system were 92% (76 of 83) in the craniocaudal view, 83% (69 of 83) in the mediolateral oblique view, and 86% (71 of 83) in the mediolateral view; the differences were not significant (P = .07-.62). Sensitivity increased to 96% (80 of 83) in the craniocaudal plus mediolateral oblique views and to 99% (82 of 83) in the craniocaudal plus mediolateral oblique plus mediolateral views. For masses, the sensitivity of the CAD system was 76% (45 of 59) in the craniocaudal view and 75% (44 of 59) in the mediolateral oblique view and increased to 93% (55 of 59) when mediolateral oblique and craniocaudal views were combined (P < .001). For microcalcifications, sensitivity was 98% (40 of 41) in the craniocaudal view and 95% (39 of 41) in the mediolateral oblique view, and this increased to 100% (41 of 41) when the mediolateral oblique and craniocaudal views were combined (P = .31). CONCLUSION: The sensitivities of the CAD system were not significantly different among these three digital mammographic views. Sensitivity for depicting masses was significantly increased (P < .001) when the craniocaudal view was added to the mediolateral oblique view.     

US of ductal carcinoma in situ.

Little is known about the ultrasonographic (US) features of ductal carcinoma in situ (DCIS) of the breast because this entity usually manifests as pure mammographic calcifications and is rarely evaluated with US. US findings were recorded in 70 patients with DCIS and then analyzed and correlated with mammographic and histologic findings. A microlobulated mass with mild hypoechogenicity, ductal extension, and normal acoustic transmission was the most common US finding in DCIS. Spiculated margins, marked hypoechogenicity, a thick echogenic rim, and posterior acoustic shadowing at US often suggested the presence of invasion. US performed with a 10-13-MHz transducer and optimal technique can be used as a complement to mammography in detecting and evaluating DCIS of the breast, as it demonstrates breast lesions associated with malignant microcalcifications in most cases. The main benefit of identifying a US abnormality in women with mammographically detected DCIS is to allow the use of US to guide interventional procedures (eg, needle biopsy, needle localization). US may also be helpful in detecting DCIS without calcifications and in evaluating disease extent in women with dense breasts. Nevertheless, further research is needed to delineate the role of US in the evaluation of patients with DCIS.     

Use of artificial neural networks (computer analysis) in the diagnosis of microcalcifications on mammography.

INTRODUCTION/OBJECTIVE: The purpose of this study was to evaluate a computer based method for differentiating malignant from benign clustered microcalcifications, comparing it with the performance of three physicians. METHODS AND MATERIAL: Materials for the study are 240 suspicious microcalcifications on mammograms from 220 female patients who underwent breast biopsy, following hook wire localization under mammographic guidance. The histologic findings were malignant in 108 cases (45%) and benign in 132 cases (55%). Those clusters were analyzed by a computer program and eight features of the calcifications (density, number, area, brightness, diameter average, distance average, proximity average, perimeter compacity average) were quantitatively estimated by a specific artificial neural network. Human input was limited to initial identification of the calcifications. Three physicians-observers were also evaluated for the malignant or benign nature of the clustered microcalcifications. RESULTS: The performance of the artificial network was evaluated by receiver operating characteristics (ROC) curves. ROC curves were also generated for the performance of each observer and for the three observers as a group. The ROC curves for the computer and for the physicians were compared and the results are:area under the curve (AUC) value for computer is 0.937, for physician-1 is 0.746, for physician-2 is 0.785, for physician-3 is 0.835 and for physicians as a group is 0.810. The results of the Student's t-test for paired data showed statistically significant difference between the artificial neural network and the physicians' performance, independently and as a group. DISCUSSION AND CONCLUSION: Our study showed that computer analysis achieves statistically significantly better performance than that of physicians in the classification of malignant and benign calcifications. This method, after further evaluation and improvement, may help radiologists and breast surgeons in better predictive estimation of suspicious clustered microcalcifications and reduce the number of biopsies for non-palpable benign lesions.     

Clustering of breast microcalcifications: revisited

AIM: To verify the diagnostic value of the traditional definition of 'clustering' of microcalcifications (more than five in the area of 1 cm(2)or 1 cm(3)) on mammography in the differential diagnosis of benign and malignant breast disease.METHODS AND MATERIALS: Three radiologists without knowledge of the final pathology retrospectively counted the number of microcalcifications per 0.25 cm(2) (0.5 x 0.5 cm) unit area on mammography in 57 pathologically proven non-palpable lesions including 26 cancers and 31 benign diseases. Pleomorphism of the microcalcifications, associated architectural distortion or mass or increased density and distribution of microcalcifications were also evaluated.RESULTS: The mean numbers of microcalcifications per 0.25 cm(2) were 16.4 in malignant and 16.7 in benign diseases (no statistically significant difference between the two groups). Pleomorphism of the microcalcifications, associated architectural distortion or mass or increased density were, however, important determining parameters. Clustering was more frequently observed in benign diseases. CONCLUSION: In this study, the mean number of microcalcifications per unit area is much larger than the traditional definition of 'clustering' and clustering itself is not effective in the differential diagnosis of benign and malignant breast lesions. Imaging features other than numbers of calcification per unit area are more important in assessing the significance of mammographic clustered microcalcifications.     

Original report. Mucocele-like tumors of the breast: mammographic and sonographic appearances

OBJECTIVE: The purpose of our study was to describe the mammographic and sonographic appearances of the mucocele-like tumor of the breast. CONCLUSION: The mucocele-like tumor is a rare lesion of the breast, the benign form of which has a nonspecific mammographic appearance. The tumor can present as indeterminate microcalcifications or as a nodule, often containing calcifications. The sonographic findings are of multiple well-defined hypoechoic oval or tubular structures with low-level internal echoes resembling complex cysts. Mucocele-like tumors of the breast can be associated with atypical hyperplasia or carcinoma. If a mucocele-like tumor is diagnosed at core needle biopsy, complete surgical excision is recommended, with careful evaluation of the entire specimen to exclude the presence of atypia or carcinoma.     

Mixed form, diffusely scattered calcifications in breast cancer with apocrine features

Diffusely scattered calcifications visible with mammography are almost always benign. Certain patterns, however, should arouse concern. For example, extensive comedocarcinoma is associated with large areas of mammographically visible calcium deposition. The authors identified 10 women in whom calcifications were visible throughout large volumes of breast tissue at mammography. The calcifications did not resemble those typical of extensive comedocarcinoma, yet they were associated with extensive breast cancer. Their mammographic pattern was characterized by a strikingly wild, chaotic appearance with profuse deposition of calcium. As in many cancers, the particles were heterogeneous, but unlike in most carcinomas, many deposits had a typically benign morphology. Histologic examination showed that even these typically benign calcifications were associated with malignant cells. The authors believe that the apocrine features displayed by many of the cancer cells in these 10 patients may explain the unusual profusion of calcium deposits.