Tissue harmonic imaging sonography of breast lesions: improved margin analysis, conspicuity, and image quality compared to conventional ultrasound.

The purpose of this preference study is to determine if tissue harmonic imaging (THI) is preferred over conventional sonography for imaging breast masses. A prospective evaluation of 73 identical image pairs (one obtained with conventional sonography, one with THI sonography) was performed, examining 25 cysts, 36 solid masses, and 12 indeterminate lesions. Each image was evaluated for lesion contrast, margins, and overall image quality using a graduated score. Statistical analysis was performed using a modified t test. For cystic and solid lesions, THI was preferred for lesion conspicuity, margin, and overall quality (P<.001). For indeterminate lesions, THI was significantly preferred for lesion conspicuity and overall quality (P<.05), but the preference for margins was not significant. Overall, THI of breast lesions was significantly preferred for lesion contrast and margin evaluation compared to conventional sonography. This modality deserves further evaluation and may improve detection and evaluation of breast lesions.

Negative predictive value of sonography with mammography in patients with palpable breast lesions.

OBJECTIVE: This study was performed to determine the negative predictive value of sonography with mammography in evaluating palpable breast lesions. MATERIALS AND METHODS: Four hundred twenty patients with 455 palpable breast lesions were retrospectively identified from our mammography database as having negative mammographic and sonographic results. For patients diagnosed with breast cancer, images and medical records were reviewed to determine whether the palpable lesion evaluated on sonography and mammography corresponded to the patient's breast cancer. On the basis of the number of breast cancers that correlated to the palpable areas imaged, the negative predictive value of sonography with mammography was determined. RESULTS: Sixty-two of the 420 patients in the study group were already diagnosed with breast carcinoma, and eight new carcinomas were diagnosed during the study period. Only one of six ipsilateral cancers corresponded to a palpable lesion that had a negative imaging evaluation. This lesion was diagnosed as an invasive lobular cancer, hard and fixed at physical examination. Imaging and clinical follow-up of the remaining patients showed no abnormality at the sites of previously investigated palpable abnormalities. The mean imaging follow-up was 25 months. The negative predictive value of sonography and mammography in the setting of a palpable lesion was 99.8%. CONCLUSION: The negative predictive value of sonography with mammography is high, and together these imaging modalities can be reassuring if follow-up is planned when the physical examination is not highly suspicious. However, if the physical examination is suspicious, biopsy should not be delayed.

Impact of core-needle breast biopsy on the surgical management of mammographic abnormalities.

OBJECTIVE: To evaluate the accuracy of percutaneous, image-guided core-needle breast biopsy (CNBx) and to compare the surgical management of patients with breast cancer diagnosed by CNBx with patients diagnosed by surgical needle-localization biopsy (SNLBx). SUMMARY BACKGROUND DATA: Percutaneous, image-guided CNBx is a less invasive alternative to SNLBx for the diagnosis of nonpalpable mammographic abnormalities. CNBx potentially spares patients with benign lesions from unnecessary surgery, although false-negative results can occur. For patients with malignant lesions, preoperative diagnosis by CNBx allows definitive treatment decisions to be made before surgery and may affect surgical outcomes. METHODS: Between 1992 and 1999, 939 patients with 1,042 mammographically detected lesions underwent biopsy by stereotactic CNBx or ultrasound-guided CNBx. Results were categorized pathologically as benign or malignant and, further, as invasive or noninvasive malignancies. Only biopsy results confirmed by excision or 1-year-minimum mammographic follow-up were included in the analysis. Patients with breast cancer diagnosed by CNBx were compared with a matched control group of patients with breast cancer diagnosed by SNLBx. RESULTS: Benign results were obtained in 802 lesions (77%), 520 of which were in patients with adequate follow-up. Ninety-five of the 520 evaluable lesions (18%) were subsequently excised because of atypical hyperplasia, mammographic-histologic discordance, or other clinical indications. There were 17 false-negative CNBx results in this group; 15 of these lesions were correctly diagnosed by excisional biopsy within 4 months of CNBx. In two patients (0.9%), delayed diagnoses of ductal carcinoma in situ were made at 15 and 19 months after CNBx. Malignant results were obtained in 240 lesions (23%), 220 of which were surgically excised from 202 patients at our institution. Two lesions diagnosed as ductal carcinoma in situ were reclassified as atypical ductal hyperplasia and considered false-positive results (0.4%). For malignant lesions, the sensitivity and specificity of CNBx for the detection of invasion were 89% and 96%, respectively. During the first surgical procedure, 115 of 199 patients (58%) diagnosed by CNBx underwent local excision; 194 of 199 patients (97%) evaluated by SNLBx underwent local excision. For patients whose initial surgery was local excision, those diagnosed before surgery by CNBx had larger excision specimens and were more likely to have negative surgical margins than were patients initially evaluated by SNLBx. Overall, patients diagnosed by CNBx required fewer surgical procedures for definitive treatment than did patients diagnosed by SNLBx. CONCLUSIONS: Diagnosis by CNBx spares most patients with benign mammographic abnormalities from unnecessary surgery. With the selective use of SNLBx to confirm discordant results, missed diagnoses are rare. When compared with SNLBx, preoperative diagnosis of breast cancer by CNBx facilitates wider initial margins of excision, fewer positive margins, and fewer surgical procedures to accomplish definitive treatment than diagnosis by SNLBx.

Silicone gel breast implant rupture, extracapsular silicone, and health status in a population of women.

OBJECTIVE: To assess whether breast implant rupture or extracapsular silicone are associated with selected symptoms of self-reported physician-diagnosed connective tissue disease (CTD). METHODS: Women with silicone gel breast implants responded to a questionnaire that included questions on health status, satisfaction with implants, symptoms of CTD, and physician-diagnosed disease. These women then had magnetic resonance imaging (MRI) of their breasts to determine the status of the implants with respect to rupture and extracapsular silicone. RESULTS: Women with breast implant rupture diagnosed by MRI were no more likely to report a diagnosis of selected CTD than those with intact implants or those with implants of indeterminate status. Women with extracapsular silicone (silicone gel outside of the fibrous scar that forms around breast implants) were more likely to report having fibromyalgia (FM, p = 0.004) or other CTD, which included dermatomyositis, polymyositis, Hashimoto's thyroiditis, mixed CTD, pulmonary fibrosis, eosinophilic fasciitis, and polymyalgia (p = 0.008) than other women in the study. The association with FM remained statistically significant when adjusted for multiple comparisons (7 diagnoses) and implant age, implant location, or implant manufacturer (p < 0.05 in all cases), but became of borderline statistical significance when adjusted for multiple comparisons and self-perceived health status (p = 0.094) or self-perceived rupture status (p = 0.051). The association with other CTD remained statistically significant when adjusted for multiple comparisons and implant location or implant manufacturer, but became borderline or insignificant when adjusted for multiple comparisons and for implant age (p = 0.051), self-perceived health status (p = 0.434), or self-perceived rupture status (p = 0.145). Logistic regression was used to compute odds ratios of self-reported diagnoses comparing women with and without extracapsular silicone. The odds ratios were 2.8 (95% CI 1.2 to 6.3) for FM, and 2.6 (95% CI 0.8 to 8.5) for other CTD after adjustment for implant age, implant location, implant manufacturer, implant type, self-perceived health, self-perceived rupture status, and site of surgery practice. CONCLUSION: These data suggest an association between extracapsular silicone from ruptured silicone breast implants and FM. If this association persists in other studies, women with silicone gel breast implants should be informed of the potential risk of developing fibromyalgia if their breast implants rupture and the silicone gel escapes the fibrous scar capsule.

In vivo breast tissue backscatter measurements with 7.5- and 10-MHz transducers.

Measurements of the ultrasound (US) backscatter coefficient (BSC) of fibroglandular and fatty breast tissues in vivo from 5.25 through 13 MHz, using the reference phantom method, are presented. Radiofrequency echo data were collected at a series of locations in the left breasts of 16 adults, age 46 to 84, and in a custom-built phantom calibrated for backscatter and attenuation. Matched regions of interest (ROIs) were then selected in these images, from which the backscatter coefficient and the backscatter frequency dependence were ratiometrically estimated, after compensation for attenuation. The mean results in fibroglandular tissues were 78.9 x 10(-3)/cm, sr at 7.2 MHz (n(ROI) = 43, n = 13) and 146 x 10(-3)/cm, sr at 10.3 MHz (n(ROI) = 19, n = 10) with frequency dependencies of f(2.28) and f(3.25). The corresponding results in subcutaneous fat were 2.59 x 10(-3)/cm, sr at 7.2 MHz (n(ROI) = 56, n = 16) and 7.08 x 10(-3)/cm, sr at 10.3 MHz (n(ROI) = 57, n = 16) with frequency dependencies of f(3.49) and f(3.43). These findings are discussed and compared to similar measurements in the literature.

The evolving role of sonography in evaluating solid breast masses.

Many investigators have attempted to use ultrasound imaging to differentiate benign from malignant solid breast masses. Studies have evaluated several generations of gray-scale imaging, Doppler, color Doppler, and power Doppler imaging, and several unconventional ultrasound techniques. Although various individual studies have shown promise, ultrasound criteria for avoiding biopsy of solid lesions have not been widely adopted. Considerable observer variability also remains an important obstacle. This article reviews the results, strengths, and weaknesses of some of the key studies addressing this issue. Fundamental criteria for a successful ultrasound model are also specified.

Prevalence of rupture of silicone gel breast implants revealed on MR imaging in a population of women in Birmingham, Alabama.

OBJECTIVE: Silicone gel breast implants have been reported to rupture, but the prevalence of implant rupture in an unreferred population of women is not known. The objective of this study was to assess the prevalence of implant rupture and the presence of extracapsular silicone gel in an unreferred population of women without regard to the absence or presence of any local or systemic symptoms. SUBJECTS AND METHODS: Women identified as part of a National Cancer Institute cohort study on breast implants, living in the Birmingham, AL, area were invited to undergo MR imaging of their current silicone gel breast implants at the Kirklin Clinic at the University of Alabama at Birmingham. Three radiologists independently examined and rated all MR images for signs of implant rupture and extracapsular silicone. RESULTS: A total of 344 women with silicone gel breast implants underwent MR imaging. Breast implant rupture was reported by at least two of three radiologists for 378 (55.0%) of the 687 implants in this study. Another 50 implants (7.2%) were rated as indeterminate (suspicious) for rupture. A majority of women in this study, 265 (77.0%) of 344, had at least one breast implant that was rated as ruptured or indeterminate. Radiologists also agreed that silicone gel could be seen outside the fibrous capsule that forms around the implant in 85 (12.4%) of the 687 implants affecting 73 women (21.2%). Factors that affected implant rupture were implant age and location (submuscular or subglandular). The median implant age at rupture was estimated to be 10.8 years with a 95% confidence interval of 8.4-13.9 years. CONCLUSION: The prevalence of silent or occult silicone gel breast implant rupture is higher than was previously suspected. Most women in this study had MR imaging evidence of at least one ruptured silicone gel breast implant.

Tubular adenomas of the breast: imaging findings with histologic correlation.

OBJECTIVE: The purpose of this study is to describe the imaging features of tubular adenomas, which are rare benign breast tumors usually found in women younger than 35 years old. CONCLUSION: In young women, tubular adenomas can look like noncalcified fibroadenomas on mammography and sonography. In older women, tubular adenomas may resemble malignant masses with microcalcifications. Awareness of these findings may help in assessing concordance between imaging and histologic findings after percutaneous core biopsy of these rare lesions.

Focal fibrosis: a common breast lesion diagnosed at imaging-guided core biopsy.

OBJECTIVE: Focal fibrosis is a benign breast lesion commonly diagnosed by imaging-guided core biopsy. The goal of this study is to determine the frequency of focal fibrosis diagnosed at core biopsy and to describe its imaging features. MATERIALS AND METHODS: A consecutive series of 894 imaging-guided breast core biopsies were reviewed, and all cases of focal fibrosis were selected. The imaging features of each lesion were characterized. All lesions had been reviewed during radiologic-histologic review sessions to assess for accurate needle positioning and concordant results. Follow-up imaging and histologic data were reviewed to document lesion stability. RESULTS: Focal fibrosis was diagnosed in 80 (8.9%) of 894 imaging-guided core biopsies: 20 (8.7%) of 229 sonographically guided biopsies and 60 (9.0%) of 665 mammographically guided biopsies. Of 75 mammographically visible lesions, 39 (52%) were masses, 29 (39%) were densities, and seven (9.3%) were clusters of calcifications. Thirty-five hypoechoic lesions were visualized on sonography: 29 (80%) were oval, and six (17%) were irregularly shaped. Six (21%) of the 28 oval masses showed posterior enhancement, four (14%) posterior shadowing, and 19 (68%) neither feature. Fifty-two (65%) of 80 patients with focal fibrosis had routine imaging follow-up; all had stable findings (mean follow-up period, 27 months). No false-negative cases were identified. CONCLUSION: Focal fibrosis most commonly appears as an enlarging solid mass or developing density on mammography or as an oval mass on sonography. Our data suggest that focal fibrosis accounts for 9% of lesions that undergo imaging-guided core biopsy and that the diagnosis can be accurately reached using imaging-guided biopsy.

Extended field-of-view two-dimensional ultrasonography of the breast: improvement in lesion documentation.

The purpose of this study was to evaluate the use of extended field-of-view two-dimensional ultrasonographic imaging for improvement in overall breast lesion documentation. Sonographic images of 59 patients with breast lesions or silicone implants were evaluated by three radiologists retrospectively to compare traditional static linear array images alone with images obtained with the addition of an extended field of view to determine if documentation of lesions was improved. The addition of extended field-of-view imaging improved lesion conspicuity by 21% over traditional images. It provided overall improvement in lesion documentation by including a reference point (nipple) or by more completely imaging large masses in 79% and implants in 69%. The larger field of view of this technique is promising as an adjunct to traditional sonography for breast lesion documentation.

Sonography of solid breast lesions: observer variability of lesion description and assessment.

OBJECTIVE: The purpose of this study was to measure the level of inter- and intraobserver agreement and to evaluate the causes of variability in radiologists' descriptions and assessments of sonograms of solid breast masses. MATERIALS AND METHODS: Sixty sonograms of solid masses were evaluated independently by five radiologists. Observers used the lexicon of a recently published benchmark report on sonographic appearances of breast masses to determine mass shape, margin, echogenicity, echo texture, presence of echogenic pseudocapsule, and acoustic transmission. Final diagnostic assessments were determined by applying the rule-based model of the same benchmark report to the radiologists' descriptions. In addition, one observer interpreted each case twice to evaluate intraobserver variability. Inter- and intraobserver variability were measured using Cohen's kappa statistic. We also investigated causes of variability in radiologists' descriptions. RESULTS: Interobserver agreement ranged from lowest for determining the presence of an echogenic pseudocapsule (kappa = .09) to highest for determining mass shape (kappa = .8). Intraobserver agreement was lowest for mass echo texture (kappa = .24) and greatest for mass shape (kappa = .79). Variability in descriptions of lesions contributed to interobserver (kappa = .51) and some intraobserver (kappa = .66) inconsistency in assessing the likelihood of malignancy. CONCLUSION: Lack of uniformity among observers' use of descriptive terms for solid breast masses resulted in inconsistent diagnoses. The need for improved definitions and additional illustrative examples could be addressed by developing a standardized lexicon similar to that of the Breast Imaging Reporting and Data System.

Stereotactic biopsy of noncalcified breast lesions: utility of vacuum-assisted technique compared to multipass automated gun technique.

The purpose of this study was to evaluate the stereotactic 14-gauge, vacuum-assisted biopsy technique in diagnosing noncalcified breast lesions. Stereotactic biopsy of 116 noncalcified breast lesions was performed with either 14-gauge, vacuum-assisted technique or multipass, automated large-core technique. The number of core samples and time required for each biopsy were compared. Outcome for each technique was compared based on recommendations after the mammographic-histologic review process. Results from surgical excision and mammographic follow-up were reviewed. The vacuum-assisted technique obtained more tissue cores per lesion than the automated gun technique, showed marginal decrease in number of repeat biopsies for discordant results, and required fewer short-term follow-up mammograms, although the difference did not achieve statistical significance. The vacuum-assisted technique can be used successfully to sample noncalcified breast masses, with marginal improvement over the automated gun technique.

Imaging-guided core biopsies in the breast.

Screening mammography programs have contributed to an overall decline in breast cancer mortality. The screening process, however, also results in detection and biopsy of many nonpalpable lesions that eventually prove to be benign, contributing to the burden of costs to our health care system. Percutaneous imaging-guided core biopsy has proven to be a safe and accurate technique for obtaining a histologic diagnosis in most patients who have screening-detected lesions; it is done at lower cost with lower resultant morbidity to the patient compared with traditional surgical excisional biopsy. I review the indications, techniques, method of correlating the histology with mammographic findings, and accreditation requirements for imaging-guided core biopsies of the breast done under mammographic (ie, stereotactic) or sonographic guidance.

Fat necrosis in the breast: sonographic features.

PURPOSE: To evaluate the ultrasonographic (US) features and evolution of fat necrosis in the breast. MATERIALS AND METHODS: The US features of 31 breast masses in 23 patients were reviewed. Fat necrosis was diagnosed on the basis of histologic (n = 20) and initial or follow-up (minimum follow-up, 15 months) mammographic (n = 11) findings. RESULTS: Sonograms demonstrated discrete masses in all but one patient. On the basis of the predominant US finding, masses were categorized as solid (n = 15), complex with mural nodules (n = 7), complex with echogenic bands (n = 4), anechoic with posterior acoustic enhancement (n = 2), anechoic with shadowing (n = 2), or no mass visible (n = 1). Distortion of the normal parenchymal architecture was seen in 21 masses. In four six masses, 1-26-month follow-up sonograms showed evolution of the US appearance. One solid mass remained solid appearing. Complex masses tended to evolve: Three became more solid appearing, and one became more cystic. No mass enlarged; two remained stable, and four decreased in size. CONCLUSION: A spectrum of US findings is associated with fat necrosis. If fat necrosis is suspected and mammographic findings are suspicious, knowledge of the US appearance and evolution of these patterns may enable imaging follow-up of these lesions rather than needless biopsy.

Intracapsular implant rupture: MR findings of incomplete shell collapse.

The objective of this study was to determine the frequency and significance of the MR findings of incomplete shell collapse for detecting implant rupture in a series of surgically removed breast prostheses. MR images of 86 breast implants in 44 patients were studied retrospectively and correlated with surgical findings at explantation. MR findings included (a) complete shell collapse (linguine sign), 21 implants; (b) incomplete shell collapse (subcapsular line sign, teardrop sign, and keyhole sign), 33 implants; (c) radial folds, 31 implants; and (d) normal, 1 implant. The subcapsular line sign was seen in 26 implants, the teardrop sign was seen in 27 implants, and the keyhole sign was seen in 23 implants. At surgery, 48 implants were found to be ruptured and 38 were intact. The MR findings of ruptured implants showed signs of incomplete collapse in 52% (n = 25), linguine sign in 44% (n = 21), and radial folds in 4% (n = 2). The linguine sign perfectly predicted implant rupture, but sensitivity was low. Findings of incomplete shell collapse improved sensitivity and negative predictive values, and the subcapsular line sign produced a significant incremental increase in predictive ability. MRI signs of incomplete shell collapse were more common than the linguine sign in ruptured implants and are significant contributors to the high sensitivity and negative predictive values of MRI for evaluating implant integrity.

Axillary lymph nodes: mammographic, pathologic, and clinical correlation.

OBJECTIVE: The purpose of this study was to determine the cause and frequency of axillary abnormalities seen mammographically and to evaluate the imaging characteristics of lymphadenopathy that are associated with malignancy. MATERIALS AND METHODS: Ninety-six axillary abnormalities seen mammographically in 94 patients were retrospectively reviewed and correlated with the clinical diagnoses and pathologic results found in the medical records. For each abnormality, the length, margins, and presence of microcalcifications were noted. Logistic regression was used to determine an association between these findings and status (benign or malignant). RESULTS: Seventy-six of 94 patients had lymphadenopathy. Eighteen of 94 patients had an abnormality other than lymphadenopathy. Because two of these 94 patients had more than one abnormality, a total of 96 abnormalities occurred, 20 of which were due to an abnormality other than lymphadenopathy. Regarding the 76 cases of lymphadenopathy, the most frequent diagnosis was nonspecific benign lymphadenopathy in 29% (n = 22) of cases, followed by metastatic breast cancer in 26% (n = 20) and chronic lymphocytic leukemia or well-differentiated lymphocytic lymphoma in 17% (n = 13). Other causes (n = 21) included collagen vascular disease, lymphomas other than well-differentiated lymphocytic lymphoma, metastatic disease from nonbreast primary site, metastatic disease from unknown primary site, sarcoidosis. HIV-related lymphadenopathy, and reactive lymphadenopathy associated with a breast abscess. An association between length of nonfatty lymph nodes and malignant status was statistically significant at the .001 level. When a length greater than 33 mm was used as a predictor of malignancy, the specificity and sensitivity were 97% and 31%, respectively. We found an association between malignancy and nonfatty lymph nodes with ill-defined or spiculated margins (p = .053). Regarding the 20 abnormalities other than lymphadenopathy, epidermal cysts (n = 7) were most prevalent. CONCLUSION: The most common axillary abnormality revealed on mammography was abnormal lymph nodes. Homogeneously dense (nonfatty) axillary lymph nodes were strongly associated with malignancy when the lymph nodes were longer than 33 mm, had ill-defined or spiculated margins, or contained intranodal microcalcifications. However, our study confirmed that in most cases benign and malignant lymph nodes cannot be distinguished from each other mammographically.