Magnetic resonance imaging for preoperative evaluation of breast cancer: a comparative study with mammography and ultrasonography

Image-guided focused ultrasound ablation of breast cancer: current status, challenges, and future directions

Image-guided focussed ultrasound (FUS) ablation is a non-invasive procedure that has been used for treatment of benign or malignant breast tumours. Image-guidance during ablation is achieved either by using real-time ultrasound (US) or magnetic resonance imaging (MRI). The past decade phase I studies have proven MRI-guided and US-guided FUS ablation of breast cancer to be technically feasible and safe. We provide an overview of studies assessing the efficacy of FUS for breast tumour ablation as measured by percentages of complete tumour necrosis. Successful ablation ranged from 20% to 100%, depending on FUS system type, imaging technique, ablation protocol, and patient selection. Specific issues related to FUS ablation of breast cancer, such as increased treatment time for larger tumours, size of ablation margins, methods used for margin assessment and residual tumour detection after FUS ablation, and impact of FUS ablation on sentinel node procedure are presented. Finally, potential future applications of FUS for breast cancer treatment such as FUS-induced anti-tumour immune response, FUS-mediated gene transfer, and enhanced drug delivery are discussed. Currently, breast-conserving surgery remains the gold standard for breast cancer treatment.

Relationship of Breast Magnetic Resonance Imaging to Outcome After Breast-Conservation Treatment With Radiation for Women With Early-Stage Invasive Breast Carcinoma or Ductal Carcinoma in Situ

Purpose

To determine the relationship of breast magnetic resonance imaging (MRI) to outcome after breast-conservation treatment (BCT) with radiation for women with early-stage invasive breast carcinoma or ductal carcinoma in situ.

Patients and Methods

A total of 756 women with early stage invasive breast carcinoma or ductal carcinoma in situ underwent BCT including definitive breast irradiation during 1992 to 2001. At the time of initial diagnosis and evaluation, routine breast imaging included conventional mammography. Of the 756 women, 215 women (28%) had also undergone a breast MRI study, and 541 women (72%) had not undergone a breast MRI study. The median follow-up after treatment was 4.6 years (range, 0.1 to 13.5 years).

Results

For the women with a breast MRI study compared with the women without a breast MRI study, there were no differences in the 8-year rates of any local failure (3% v 4%, respectively; P = .51) or local-only first failure (3% v 4%, respectively; P = .32). There were also no differences between the two groups for the 8-year rates of overall survival (86% v 87%, respectively; P = .51), cause-specific survival (94% v 95%, respectively; P = .63), freedom from distant metastases (89% v 92%, respectively; P = .16), or contralateral breast cancer (6% v 6%, respectively; P = .39).

Conclusion

The use of a breast MRI study at the time of initial diagnosis and evaluation was not associated with an improvement in outcome after BCT with radiation.

Diagnosis of the intraductal component of invasive breast cancer: assessment with mammography and sonography

OBJECTIVE

The aim of this study was to investigate mammographic and sonographic features and their sensitivities for depiction of the intraductal component associated with invasive ductal carcinoma (IDC).

METHODS

During a 1-year period, 132 patients with IDC underwent surgical treatment. All patients underwent mammography and high-resolution sonography, and the findings were reported according to the American College of Radiology's Breast Imaging Reporting and Data System lexicon. Tumors were classified as "pure IDC" and "IDC with an intraductal component" by histopathologic evaluation. We compared mammographic and sonographic features between the above 2 groups and attempted to correlate them with histopathologic findings. We also investigated separate and combined sensitivities, specificities, and accuracies of both mammography and breast sonography for showing intraductal components. Finally, imaging measurements were compared with pathologic measurements.

RESULTS

One hundred four (79%) of the 132 IDCs contained an intraductal component. Patients with IDC with an intraductal component showed calcifications on mammography and showed an echogenic halo, duct dilatation, calcifications, and increased vascularity in surrounding tissue on sonography more frequently than patients with pure IDC. The sensitivities of mammography, sonography, and their combined assessment for detection of an intraductal component were 55%, 80%, and 86%, respectively. The combined assessment (r = 0.90) measured the extent of the tumor more accurately than mammography (r = 0.71) or sonography (r = 0.79) separately.

CONCLUSIONS

Combined assessment with mammography and sonography offers more accurate information for the presence of an intraductal component and the extent of a tumor than each separate assessment.

Influence of preoperative MRI on the surgical management of patients with operable breast cancer

PURPOSE

Evaluation of the impact of preoperative magnetic resonance imaging (MRI) of the breast on the clinical management of patients with operable breast cancer (BC).

METHODS

Retrospective analysis of 160 patients with operable breast cancer (stages Tis through T4), treated from 2002 through 2004. All patients underwent a full mammographic assessment, high frequency breast ultrasound, and breast MRI. The impact of preoperative MRI was evaluated for each patient with regard to changes in the therapeutic procedure. Patient and tumor characteristics were analyzed to identify possible patient subgroups that predominantly would benefit from preoperative MRI.

RESULTS

Preoperative MRI affected the clinical management in 44 of 160 patients (27.5%). In 30 cases (18.75%) additional in situ or invasive cancers or a more widespread tumor extent were diagnosed correctly which went undetected by clinical palpation, mammography, and breast ultrasound. In 14 cases (8.75%) additional surgical procedures were performed based on suspicious MRI findings that turned out to be benign in final pathology. Age, menopausal status, breast density, tumor characteristics (type, tumor size, grading), ER-, PR- and HER2-receptor features did not significantly differ between patients in which breast MRI affected the clinical management and patients that experienced no additional information from MRI.

CONCLUSIONS

Preoperative breast MRI changes surgical management of patients with operable breast cancer. MRI detects additional invasive carcinoma and proves to be a powerful supplement to the conventional work-up in the clinical management of breast cancer. This advantage is independent from patients- and tumor-specific characteristics.

Contrast-enhanced 3.0-T breast MRI for characterization of breast lesions: increased specificity by using vascular maps

PURPOSE

To assess the diagnostic accuracy of contrast-enhanced 3.0-T breast magnetic resonance imaging (MRI) for differentiating benign from malignant breast masses and subsequently to test if specificity could be further improved by scoring of the overall ipsilateral breast vascularity.

MATERIALS AND METHODS

Fifty-four patients were prospectively enrolled in the study and underwent contrast-enhanced 3.0-T breast MRI. MR images were evaluated and classified according to the MRI BI-RADS lexicon criteria. Lesion size, number of lesions, and localization in the breast were systematically assessed. Maximum intensity projections (MIPS) were obtained by using high-resolution contrast-enhanced (0.1 mmol/kg gadobutrol) fat-saturated T1-weighted images. Breast vascularization was scored according to the methods from Sardanelli et al. by measuring the number, diameter, and length of the vessels on the MIPS. The score ranged from 0 (indicating absent or low breast vascularity) to 3 (indicating high breast vascularity).

RESULTS

Final analysis of 56 lesions revealed 25 (45%) malignant lesions and 31 (55%) benign lesions. Correlation with the MRI BI-RADS classification revealed cancer in none (0%) of the BI-RADS II lesions, in 1 (12%) of the BI-RADS III lesions, in 5 (83%) of the BI-RADS IV lesions, and in 19 (100%) of the BI-RADS V lesions. Based on morphologic and kinetic data analysis, the sensitivity and specificity of 3.0-T breast MRI was 100% (25/25) and 74% (23/31), respectively. After adjustment for the breast vascularity score, specificity significantly (p = 0.048) increased to 87% (27/31) without affecting sensitivity.

CONCLUSION

Diagnostic accuracy of contrast-enhanced 3.0-T breast MRI increased significantly when the vascularity score was added to the standard morphologic and kinetic data analysis, resulting in a specificity of 87% without affecting sensitivity, which remained 100%.

Breast MRI Wire-Guided Excisional Biopsy: Specimen Size as Compared to Mammogram Wire-Guided Excisional Biopsy and Implications for Use

BACKGROUND

Breast magnetic resonance imaging (MRI) has been implemented as a screening tool for early detection and as a diagnostic test in the management of breast cancer. Lesions identified by MRI but not amenable to conventional biopsy techniques require MRI wire-guided excisional biopsy (MRIbx). We hypothesized that more tissue would be resected with MRIbx compared to Mammobx. We also sought to evaluate factors that might predict the presence of breast cancer in patients undergoing MRIbx.

METHODS

We reviewed consecutive cases of breast MRIbx from 2004 to 2006 performed by seven surgeons. MRI was performed in patients with either a synchronous breast cancer or significant risk factors. Lesions visualized only by MRI underwent diagnostic MRIbx. The control group was comprised of consecutive cases that underwent diagnostic Mammobx during the same time period. The volumes of tissue resected, overall and by pathologic outcome, were compared.

RESULTS

Seventy-one patients, with a mean age of 48, underwent MRIbx. Eleven (15.5%) invasive breast cancers and eight cases (11.3%) of ductal carcinoma in situ (DCIS) were identified. The median volume of tissue resected was significantly greater than that in the Mammobx group (28.8 cm3 vs 21.1 cm3, respectively). DCIS-containing MRIbx specimens were significantly larger than benign or invasive cancer-containing specimens. There was no significant overall association between either the indication for MRIbx or the size of the MRI lesion and the frequency of cancer.

CONCLUSIONS

In patients undergoing breast MRIbx, 27% were found to have DCIS or invasive breast cancer. MRIbx was associated with significantly larger specimen volumes than Mammobx.

Fusion of Magnetic Resonance and Scintimammography Images for Breast Cancer Evaluation: A Pilot Study

BACKGROUND

To achieve a more specific method to estimate the real size of breast cancer, we have developed a method to fuse magnetic resonance imaging (MRI) and scintimammography (SM) images. The aim of this study was to assess the feasibility of this method and to evaluate its accuracy to measure the size of breast cancer compared with MRI alone, mammography, and clinical examination, employing pathologic size as the gold standard.

METHODS

Twenty consecutive breast cancer women at stages IIA-IIIA, scheduled for mastectomies, underwent SM with (99m)Tc-sestamibi and MRI with gadolinium 2-10 days before surgery. All patients had had recent mammographies and were examined clinically. Software was developed in visual language to perform the fusion between MRI and SM images and tumor measurements (MRI/SM). The tumor size, in 3 diameters (anteroposterior, longitudinal, and transverse), for each examination was correlated with pathological measurements using linear regression.

RESULTS

The MRI/SM technique was successfully performed in all patients, and the principal tumor was measured by this method. The MRI/SM cancer measurements correlated better with pathology than MRI, mammography, and clinical exam in all diameters analyzed (r = 0.88, 0.81, 0.81; SE = 0.11, 0.14, 0.11 in anteroposterior, longitudinal, and transverse diameters, respectively).

CONCLUSIONS

The MRI/SM is a feasible technique and appears to be more accurate than other examinations (MRI alone, mammography, and clinical exam) to measure breast cancer size.

MRI of the breast for the detection and assessment of the size of ductal carcinoma in situ

OBJECTIVE

The aim of the study was to compare the accuracy of magnetic resonance imaging (MRI) and mammography for the detection and assessment of the size of ductal carcinoma in situ (DCIS).

MATERIALS AND METHODS

The preoperative contrast-enhanced MRI and mammography were analyzed in respect of the detection and assessment of the size of DCIS in 72 patients (age range: 30-67 years, mean age: 47 years). The MRI and mammographic measurements were compared with the histopathologic size with using the Pearson's correlation coefficients and the Mann-Whitney u test. We evaluated whether the breast density, the tumor nuclear grade, the presence of comedo necrosis and microinvasion influenced the MRI and mammographic size estimates by using the chi-square test.

RESULTS

Of the 72 DCIS lesions, 68 (94%) were detected by MRI and 62 (86%) were detected by mammography. Overall, the Pearson's correlation of the size between MRI and histopathology was 0.786 versus 0.633 between mammography and histopathology (p < 0.001). MRI underestimated the size by more than 1 cm (including false negative examination) in 12 patients (17%), was accurate in 52 patients (72%) and overestimated the size by more than 1 cm in eight patients (11%) whereas mammography underestimated the size in 25 patients (35%), was accurate in 31 patients (43%) and overestimated the size in 16 patients (22%). The MRI, but not the mammography, showed significant correlation for the assessment of the size of tumor in noncomedo DCIS (p < 0.001 vs p = 0.060). The assessment of tumor size by MRI was affected by the nuclear grade (p = 0.008) and the presence of comedo necrosis (p = 0.029), but not by the breast density (p = 0.747) or microinvasion (p = 0.093).

CONCLUSION

MRI was more accurate for the detection and assessment of the size of DCIS than mammography.

Role of ultrasonography and MRI in the detection of wide intraductal component of invasive breast cancer—a prospective study

AIM

To compare the role of ultrasound (US) and magnetic resonance imaging (MRI) in the detection of extent and direction of intraductal components around invasive breast cancer in comparison with histopathological findings.

MATERIALS AND METHODS

In 60 invasive breast cancers (59 patients), US features of the intraductal components were classified as: (a) solid ductal dilatation radiating from the tumour, (b) the presence of a satellite lesion in the same segment without ductal dilatation, (c) ductal dilatation between the main tumour and the satellite lesion. The criteria for the detection of intraductal components by MRI were as follows: (a) strand-like enhancement on the margin of the main tumour, (b) satellite lesions around the main tumour, or (c) bridging enhancement between the main tumour and the satellite lesion. The direction of the intraductal components was classified as towards the nipple and towards the periphery.

RESULTS

Wide intraductal components (>or=15 mm) towards the nipple were proven histopathologically in 17 of 59 (28.8%) cancers, and wide intraductal components towards the periphery were proven histopathologically in three out of 60 (5.0%) cancers. One cancer was located too close to the nipple and it was not possible to measure the intraductal component towards the nipple. US and MRI could accurately detect wide intraductal components towards the nipple in 14 and 8 cancers, respectively, out of 17 cancers. Sensitivity, specificity and accuracy for detection of wide intraductal components towards the nipple by US were 87.5, 88.3, and 88.1%, respectively. Sensitivity, specificity and accuracy for detection of wide intraductal components towards the nipple by MRI were 50, 79.1, and 72.1%, respectively. When the results of both diagnostic methods namely US and MRI were combined, sensitivity rose to 93.7%, specificity was 72.1% and accuracy was 78.0%.

CONCLUSION

Although ultrasound is more sensitive than MRI in the delineation of intraductal extension towards the nipple, there is no statistically significant difference in overall accuracy between the two modalities.

The efficacy of breast MRI in predicting breast conservation therapy

BACKGROUND

Breast conservation therapy (BCT) has equal efficacy compared to mastectomy in treating breast cancer. Accurate pre-operative measurement of tumor size can limit re-excision procedures. Breast MRI may improve pre-operative evaluation of extent of disease.

OBJECTIVE

To examine the correlation of extent of disease on breast MRI with pathologic data to determine the utility of breast MRI in surgical planning of BCT.

METHODS

We retrospectively reviewed our prospective database of women undergoing breast MRI. We identified 115 women with breast cancer who underwent a breast MRI and a surgical resection from 2000 to 2003. We compared patients with high-grade tumors (HG, n = 40) to patients with low grade (LG, n = 75).

RESULTS

The size of the tumor on MRI correlated with the pathologic size for HG tumors (HG R = 0.76 vs. LG R = 0.45, P = 0.033). Mastectomy was performed in 53 patients. In 10 patients with LG tumors, the MRI findings overestimated their disease. In 11 out of 115 patients the primary tumor or a second tumor was only seen by MRI.

CONCLUSION

Breast MRI does change surgical management by detecting additional malignancies. Breast MRI is accurate in staging extent of disease in the breast in patients with HG tumors.

Clinical Significance of Multidetector-Row Computed Tomography in Breast Surgery

Several reports support the association of higher ipsilateral breast tumor recurrence rates with positive or intermediate margins compared with negative pathologic margins. Precise evaluation of tumor extension and adequate surgical margin are important factors affecting tumor recurrence after breast-conserving surgery (BCS). Many studies have reported the utility of magnetic resonance imaging (MRI) for diagnosing the tumor extension of breast cancer, but few have evaluated the utility of multidetector-row computed tomography (MDCT). The results of this study show the clinical significance of MDCT for detecting cancer extension and demonstrate the clinical role of MDCT in BCS. Subjects comprised 136 patients grouped into two categories based on whether or not tumor extension was evaluated with MDCT preoperatively. The positive surgical margin rate and breast conservation rate were analyzed in each group and the clinical role of MDCT in BCS was evaluated. Moreover, evaluation of intraductal extension was done both with MDCT and histologically, and computed tomography (CT)-pathologic correlations were examined retrospectively. Finally, the margin-positive cases were analyzed in relation to their clinical characteristics. Sensitivity, specificity, positive predictive value, and negative predictive value for detection of the intraductal component were 71.8%, 85.7%, 82.1%, and 76.9%, respectively. The positive surgical margin rate and conservation rate are 7.46% and 81.9%, respectively, for those who were diagnosed with MDCT preoperatively; their corresponding rates without MDCT were 16.67% and 67.9%. Most margin-positive patients have remarkable lymphatic space invasion. Positive surgical margins were often recognized toward the nipple. For diagnosing the intraductal extension, MDCT shows sufficient diagnosability. Moreover, MDCT can provide appropriate information for the determination of adequate surgical margins and contribute to increases in breast conservation rates.

The value of magnetic resonance imaging in diagnosis and size assessment of in situ and small invasive breast carcinoma

BACKGROUND

The value of magnetic resonance imaging (MRI) in diagnosis and size assessment of ductal carcinoma-in-situ (DCIS) and DCIS with small (<10 mm) invasive carcinoma was evaluated.

METHODS

Fifty-four patients with DCIS and 12 patients with DCIS and small invasive carcinoma were included. Mammographic (N = 64) and MRI (N = 22) images were retrospectively reviewed. Correlation coefficients were calculated to assess differences in size between imaging and histopathologic examination.

RESULTS

Mammographic rate of detection for DCIS was 48/52 (92%) and for DCIS with small invasive carcinoma, 10/12 (83%). MRI revealed 1 false negative case and the rate of detection for DCIS was 16/17 (94%). Correlation of mammographic size with histopathologic size was r = .44 (P < .01) and r = 0.49 (P = .03) for MRI. Mammography underestimated lesion size by 5 mm or more in 47%, whereas with MRI size was adequately assessed in 43% and overestimated in 38%.

CONCLUSIONS

DCIS can be visualised on MRI with high sensitivity, although tumor size can be overestimated.

Chemical mapping of tumor progression by FT-IR imaging: towards molecular histopathology

Fourier-transform infrared (FT-IR) spectro-imaging enables global analysis of samples, with resolution close to the cellular level. Recent studies have shown that FT-IR imaging enables determination of the biodistribution of several molecules of interest (carbohydrates, lipids, proteins) for tissue analysis without pre-analytical modification of the sample such as staining. Molecular structure information is also available from the same analysis, notably for protein secondary structure and fatty acyl chain peroxidation level. Thus, several cancer markers can be identified from FT-IR tissue images, enabling accurate discrimination between healthy and tumor areas. FT-IR imaging applications are now able to provide unique chemical and morphological information about tissue status. With the fast image acquisition provided by modern mid-infrared imaging systems, it is now envisaged to analyze cerebral tumor exereses in delays compatible with neurosurgery. Accordingly, we propose to take FT-IR imaging into consideration for the development of new molecular histopathology tools.

A new automated software system to evaluate breast MR examinations: improved specificity without decreased sensitivity

OBJECTIVE

We sought to compare the accuracy of breast MRI interpretations with and without a new software application (CADstream) that provides automated evaluations of breast MR examinations.

MATERIALS AND METHODS

Thirty-three consecutive lesions seen only on MRI (nine malignant, 24 benign) were evaluated with and without the automated software system. Automated analyses of kinetic enhancement for each lesion were recorded at 50%, 80%, and 100% enhancement thresholds. Computer-assisted analyses included presence or absence of "significant" enhancement and classification of enhancement patterns into percent volumes of washout, plateau, and persistent enhancement. Fisher's exact tests were performed to compare the likelihood of malignancy based on the presence of software-defined significant enhancement at the three thresholds. Enhancement profiles of malignant versus benign lesions were compared using the Student's t test.

RESULTS

All malignant lesions showed significant enhancement at all thresholds. Compared with the unassisted interpretations, the computer-assisted analyses yielded false-positive rates that were reduced by 25% at a 50% threshold (not significant [NS]), 33% at an 80% threshold (p = 0.05), and 50% at a 100% threshold for enhancement (p < 0.01). There were no significant differences between enhancement profiles of benign and malignant lesions, with all lesions showing a wide range of washout, plateau, and persistent patterns of enhancement.

CONCLUSION

New automated software applied to interpret breast MR examinations accurately showed significant enhancement in all the malignant lesions while depicting 12 of 24 benign lesions as showing insignificant enhancement. If these results are validated by a larger study, the number of unnecessary biopsies of MR lesions could be reduced without a concomitant decrease in cancer detection.

Comparison of MDCT and MRI for Evaluating the Intraductal Component of Breast Cancer

OBJECTIVE

The purpose of our study was to compare the accuracy of MDCT and MRI for evaluating the intraductal component of breast cancer.

MATERIALS AND METHODS

Sixty-nine patients with histologically proven invasive carcinoma underwent MDCT and MRI. Retrospectively, two radiologists performed a blinded review of the MDCT and MRI. Cases with intraductal component enhancement were classified into two morphologic types: ductal extension and segmental distribution. The lengths of the main tumor and of the intraductal component were measured in cases with ductal extension. For cases with segmental distribution, only the maximum length of the tumor was measured.

RESULTS

The sensitivity, specificity, and accuracy in detecting the intraductal component were 61%, 88%, and 71%, respectively, using MDCT; and 75%, 88%, and 80%, respectively, using MRI. MRI revealed the presence of the intraductal component with significantly higher sensitivity than did MDCT (p = 0.031). In the analysis of the length of the intraductal component in cases with ductal extension, which had relatively small intraductal components, underestimation by 15 mm or more was significantly less frequent with MRI than with MDCT (p = 0.008). There was no significant difference between MDCT and MRI in the evaluation of the maximum length of tumors in cases with segmental distribution, which had relatively large intraductal components.

CONCLUSION

Compared with MDCT, MRI revealed the presence of the intraductal component with higher sensitivity and equivalent specificity. In cases with ductal extension, MRI is more precise than MDCT for determination of the margin for surgical removal, with less underestimation of the extent of the intraductal component.

A Clinical Oncology Perspective on the Use of Breast MR

MR imaging of the breast detects additional carcinoma in as many as 30% of women thought to have localized disease by clinical examination and mammography. This has led some to advocate its routine use in the preoperative evaluation of breast cancer patients. However, local failure rates in patients selected for breast conservation by conventional methods are less than 5% at 10 years, suggesting that he majority of this disease is controlled with radiotherapy. The potential role of MR in the preoperative evaluation and postoperative follow-up of patients with early-stage breast cancer is discussed.

MRI-guided needle localization of suspicious breast lesions: results of a freehand technique

Magnetic resonance imaging (MRI) can detect clinically and mammographically occult breast lesions. In this study we report the results of MRI-guided needle localization of suspicious breast lesions by using a freehand technique. Preoperative MRI-guided single-needle localization was performed in 220 patients with 304 MRI-only breast lesions at our hospital between January 1997 and July 2004. Procedures were performed in an open 0.5-T Signa-SP imager allowing real-time monitoring, with patient in prone position, by using a dedicated breast coil. MRI-compatible hookwires were placed in a noncompressed breast by using a freehand technique. MRI findings were correlated with pathology and follow-up. MRI-guided needle localization was performed for a single lesion in 150 patients, for two lesions in 56 patients, and for three lesions in 14 patients. Histopathologic analysis of these 304 lesions showed 104 (34%) malignant lesions, 51 (17%) high-risk lesions, and 149 (49%) benign lesions. The overall lesion size ranged from 2.0-65.0 mm (mean 11.2 mm). No direct complications occurred. Follow-up MRI in 54 patients showed that two (3.7%) lesions were missed by surgical biopsy. MRI-guided freehand needle localization is accurate and allows localization of lesions anterior in the breast, the axillary region, and near the chest wall.

Advances in optical spectroscopy and imaging of breast lesions

A review is presented of recent advances in optical imaging and spectroscopy and the use of light for addressing breast cancer issues. Spectroscopic techniques offer the means to characterize tissue components and obtain functional information in real time. Three-dimensional optical imaging of the breast using various illumination and signal collection schemes in combination with image reconstruction algorithms may provide a new tool for cancer detection and treatment monitoring.

Detection of intraductal component around invasive breast cancer using ultrasound: Correlation with MRI and histopathological findings

PURPOSE

The purpose of this study was preoperatively to diagnose the intraductal component, which is indispensable in planning for breast conservation therapy, and also to minimize local recurrence. This study investigated the efficacy of ultrasound (US) in the detection of intraductal component in comparison with magnetic resonance imaging (MRI) and histopathological findings.

PATIENTS AND METHODS

In 47 patients with invasive breast cancer, US features of the intraductal component were classified as (a) solid ductal dilatation radiating from the tumor, (b) presence of satellite lesion in the same segment without ductal dilatation, and (c) ductal dilatation between the main tumor and satellite lesion. MRI depicted intraductal extension as the most enhanced area during the first or second phase of the dynamic study. Other criteria for the detection of the intraductal component by MRI were as follows: (a) a satellite lesion around the main tumor, (b) bridging enhancement between the main tumor and satellite lesions. The extent of the intraductal component was measured and classified as mimimal (0-5 mm), moderate (6-15 mm) or wide (>15 mm).

RESULTS

In 28 of 47 (60.0%) patients, a wide intraductal component of more than 15 mm was proved histopathologically. Of 28 patients, US and MRI could accurately detect wide intraductal components in 16 patients and 14 patients, respectively. Sensitivity, specificity, and accuracy were 57.1%, 84.2%, and 68.1% respectively for US and 50.0%, 89.5% and 65.9% for MRI, respectively. When both US and MRI results were combined, sensitivity, specificity, and accuracy were 75.0%, 84.2%, and 78.7%.

CONCLUSION

Current US examination depicted the intraductal component of breast cancer more accurately than MRI. Further, our study suggests that the use of both US and MRI together is complementary and offers more advantage than US alone.

Contrast-enhanced MRI in breast cancer patients eligible for breast-conserving therapy: complementary value for subgroups of patients

The aim of this study was to identify patients prior to breast-conserving therapy (BCT) who have complementary value of contrast-enhanced magnetic resonance imaging (MRI) over conventional imaging in the assessment of tumor extent. All patients were eligible for BCT according to conventional imaging, and underwent preoperative MRI as part of this study. One hundred and sixty-five patients (166 tumors) were included. MRI was defined to have complementary value if conventional imaging underestimated or overestimated tumor extent (by more than 10 mm compared to histology) and MRI assessed the extent accurately. Logistic regression was employed to identify characteristics that are predictive of the complementary value of preoperative MRI. MRI had complementary value in 39 cases (23%). Patients <58 years old with irregular lesion margins at mammography and discrepancy in tumor extent by more than 10 mm between mammography and ultrasonography had a 3.2x higher chance of accurate assessment at MRI (positive predictive value 50%, negative predictive value 84%, p=0.0002). Preoperative MRI in patients eligible for BCT is more accurate than conventional imaging in the assessment of tumor extent in approximately one out of four patients. Subgroups of patients in whom MRI has complementary value may be defined by the differences in clinical and imaging features.

MRI detection of distinct incidental cancer in women with primary breast cancer studied in IBMC 6883

BACKGROUND

Prior single institution studies suggest MRI may improve the assessment of the extent of cancer within the breast, and thus reduce the risk of leaving macroscopic disease in the breast following breast conservation therapy. We report on the rate of MRI and mammography detection of foci of distinct incidental cancer in a prospective, multi center trial involving 426 women with confirmed breast cancer at 15 institutions in the US, Canada, and Germany.

METHODS

Women underwent mammography and MRI prior to biopsy of the suspicious index lesion. Additional incidental lesions (IL) greater than 2 cm from the index lesion that were detected by mammography and MRI were noted and characterized. Biopsy recommendations were associated with ILs given an assessment of suspicious or highly suspicous (BiRads 4 and 5). These assessments were considered a positive test.

RESULTS

MRI had a significantly higher yield of confirmed cancer ILs than mammography (0.18 (95%CI: 0.142-0.214) for MRI versus 0.072 (95%CI: 0.050-0.100) for mammography). The cancer ILs detected by MRI alone appeared to be similar to those detected by mammography with respect to size and histology. The percentage of biopsies of ILs that resulted in a cancer diagnosis was similar between the modalities (MRI 0.72(95%CI: 0.6-0.81); Mammography 0.85 (95%CI: 0.62-0.96)).

CONCLUSIONS

These results suggest that consideration needs to be given regarding the integration of breast MRI into the pretreatment evaluation of women seeking breast conservation therapy.

Correlation of targeted ultrasound with magnetic resonance imaging abnormalities of the breast

BACKGROUND

Magnetic resonance imaging (MRI) of the breast is highly sensitive for cancer. However, MRI frequently detects additional lesions that mandate further evaluation. The intent of this study was to assess the ability of targeted ultrasound to identify additional lesions detected on MRI in patients undergoing evaluation for breast cancer.

METHODS

Between January 1, 1999, and July 15, 2004, 270 women underwent breast MRI at Grant Medical Center. MRI was obtained in 191 women during evaluation for documented or suspected breast cancer. Fifty-two patients had additional suspicious lesions on MRI, prompting targeted ultrasound; these patients constituted our study population.

RESULTS

Seventy-five additional suspicious lesions were detected on breast MRI in 52 women. Two women underwent mastectomy without targeted ultrasound. Targeted ultrasound identified 65 of the remaining 73 lesions (89%). Eight lesions (11%) were not visible on targeted ultrasound.

CONCLUSION

Targeted ultrasound can be a reliable method to correlate MRI abnormalities in breast cancer patients.

The Impact of MRI on the Treatment of DCIS

Magnetic resonance imaging (MRI) has been shown to detect occult invasive breast cancers with a sensitivity of 97 per cent to 100 per cent. Mammography and ultrasonography does not accurately assess the extent of ductal carcinoma in situ (DCIS), which results in a high reoperation rate. Breast MRI can improve the surgical planning in women with DCIS, improving the adequacy of initial treatment while reducing reoperation. We examined 54 patients with predominantly DCIS (>50%) who underwent breast MRI from January 2003 to November 2004. MRI altered the surgical management in 14 (26%) patients: unilateral changed to bilateral mastectomy (5); lumpectomy or reexcision to mastectomy (3); unilateral lumpectomy or mastectomy had additional biopsies for lesions detected by MRI in the ipsilateral or contralateral breast (6). There were 8 true-positives and 7 false-positives: sensitivity 86 per cent, positive predictive value 84 per cent. MRI changed the surgical management to more appropriate therapy in 15 per cent of patients avoiding additional surgery, while 11 per cent underwent negative surgical interventions. Breast MRI is a sensitive diagnostic imaging tool in patients with DCIS. However, any suspicious finding should be biopsied before a definitive operation is planned.

Combining near-infrared tomography and magnetic resonance imaging to study in vivo breast tissue: implementation of a Laplacian-type regularization to incorporate magnetic resonance structure

An imaging system that simultaneously performs near infrared (NIR) tomography and magnetic resonance imaging (MRI) is used to study breast tissue phantoms and a healthy woman in vivo. An NIR image reconstruction that exploits the combined data set is presented that implements the MR structure as a soft-constraint in the NIR property estimation. The algorithm incorporates the MR spatially segmented regions into a regularization matrix that links locations with similar MR properties, and applies a Laplacian-type filter to minimize variation within each region. When prior knowledge of the structure of phantoms is used to guide NIR property estimation, root mean square (rms) image error decreases from 26 to 58%. For a representative in vivo case, images of hemoglobin concentration, oxygen saturation, water fraction, scattering power, and scattering amplitude are derived and the properties of adipose and fibroglandular breast tissue types, identified from MRI, are quantified. Fibroglandular tissue is observed to have more than four times as much water content as adipose tissue, almost twice as much blood volume, and slightly reduced oxygen saturation. This approach is expected to improve recovery of abnormalities within the breast, as the inclusion of structural information increases the accuracy of recovery of embedded heterogeneities, at least in phantom studies.

Extracorporeal high intensity focused ultrasound treatment for patients with breast cancer

PURPOSE

To investigate the safety, efficacy and feasibility of using high-intensity focused ultrasound (HIFU) as a non-invasive treatment for patients with breast cancer.

PATIENTS AND METHODS

Twenty-two patients with breast cancer were enrolled into this non-randomized prospective trial. Disease TNM stage was classified as stage I in 4 patients, stage II(A) in 9 patients, stage II(B) in 8 patients, and stage IV in 1 patient. Tumor size ranged from 2 to 4.8 cm in diameter (mean 3.4 cm). All patients received chemotherapy, radiation and tamoxifen, following HIFU for the primary lesions. Outcome measures included radiological and pathologic assessment of the treated tumor, cosmesis, and local recurrence. A cumulative survival rate is calculated by using the Kaplan-Meier method.

RESULTS

No severe complications were encountered after HIFU. Post-operative imaging demonstrated positive response and regression of all treated lesions. Follow-up biopsy revealed coagulation necrosis of target tumor and subsequent replacement by fibroblastic tissue. After a median follow-up of 54.8 months, 1 patient died, 1 was lost to follow-up, and 20 were still alive. Two of 22 patients developed local recurrence. Five-year disease-free survival and recurrence-free survival were 95% and 89%, respectively. Cosmetic result was judged as good to excellent in 94% of patients.

CONCLUSIONS

HIFU treatment is safe, effective, and feasible for patients with breast cancer. But, large-scale, multiple-center clinical trials will be needed to determine the future role of this novel modality.

An improved 1H magnetic resonance spectroscopic imaging technique for the human breast: preliminary results

The high sensitivity but poor specificity of magnetic resonance imaging for detecting breast cancer has stimulated interest in magnetic resonance spectroscopic imaging (MRSI) as a tool to improve specificity and reduce the number of benign biopsies. The challenge of applying 1H MRSI to the diagnosis of cancer in the human breast is the need for robust lipid suppression and a clinically acceptable acquisition time. We present an improved 1H MRSI technique that uses an independently optimized chemical-shift-selective for lipid suppression and weighted elliptical k-space sampling combined with a Hamming filter for improved sampling efficiency.

Rates of reexcision for breast cancer after magnetic resonance imaging-guided bracket wire localization

BACKGROUND

We performed this study to determine rates of close or transected cancer margins after magnetic resonance imaging-guided bracket wire localization for nonpalpable breast lesions.

STUDY DESIGN

Of 243 women undergoing MRI-guided wire localizations, 26 had MRI bracket wire localization to excise either a known cancer (n = 19) or a suspicious MRI-detected lesion (n = 7). We reviewed patient age, preoperative diagnosis, operative intent, mammographic breast density, MRI lesion size, MRI enhancement curve and morphology, MRI Breast Imaging Reporting and Data System (BI-RADS) assessment code, number of bracket wires, and pathology size. We analyzed these findings for their relationship to obtaining clear margins at first operative excision.

RESULTS

Twenty-one of 26 (81%) patients had cancer. Of 21 patients with cancer, 12 (57%) had negative margins at first excision and 9 (43%) had close/transected margins. MRI size > or = 4 cm was associated with a higher reexcision rate (7 of 9, 78%) than those < 4 cm (2 of 12, 17%) (p = 0.009). MRI BI-RADS score, enhancement curve, morphology, and preoperative core biopsy demonstrating ductal carcinoma in situ (DCIS) were not predictive of reexcision. The average number of wires used for bracketing increased with lesion size, but was not associated with improved outcomes. On pathology, cancer size was smaller in patients with negative margins (12 patients, 1.2 cm) than in those with close/transected margins (9 patients, 4.6 cm) (p < 0.001). Reexcision was based on close/transected margins involving DCIS alone (6, 67%), infiltrating ductal carcinoma and DCIS (2, 22%), or infiltrating ductal carcinoma alone (1, 11%). Reexcision pathology demonstrated DCIS (3, 33%), no residual cancer (5, 55%), and 1 patient was lost to followup (1, 11%). Interestingly, cancer patients who required reexcision were younger (p = 0.022), but breast density was not associated with reexcision.

CONCLUSIONS

To our knowledge, this is the first report of MRI-guided bracket wire localization. Patients with MRI-detected lesions less than 4 cm had clear margins at first excision; larger MRI-detected lesions were more likely to have close/transected margins. Reexcision was often because of DCIS and was the only pathology found at reexcision, perhaps because MRI is more sensitive for detecting invasive carcinoma than DCIS.

The role of magnetic resonance imaging in diagnosis and management of breast cancer

A review of the literature on the current applications of breast magnetic resonance imaging (MRI) indications, their rationale and their place in diagnosis and management of breast cancer was given. Contrast-enhanced breast MRI is developing as a valuable adjunct to mammography and sonography. Its high sensitivity for invasive breast cancer establishes its superiority in evaluation of multifocality/multicentricity, tumor response to neoadjuvant chemotherapy, detection of recurrence, and staging. Emerging applications include spectroscopy, usage of new contrast agents, and MRI-guided interventions, including noninvasive treatment of breast cancer. Its potential benefit in screening high-risk women has yet to be established with prospective studies, particularly with regard to false positive results.

Dynamic contrast-enhanced MRI and sonography in patients receiving primary chemotherapy for breast cancer

We compared dynamic contrast-enhanced MRI (DCE-MRI) and sonography (US) for monitoring tumour size in 21 patients with breast cancer undergoing primary chemotherapy (PCT) followed by surgery. The correlation between DCE-MRI and US measurements of tumour size, defined as the product of the two major diameters, was 0.555 (P=0.009), 0.782 (P<0.001), and 0.793 (P<0.001) at baseline, and after two and four cycles of PCT, respectively. The median tumour size was significantly larger when measured by DCE-MRI than by US at baseline (1472 vs 900 mm(2), P<0.001) and after two cycles of PCT (600 vs 400 mm(2), P=0.009). After PCT, the median tumour size measured by the two techniques was similar (256 vs 289 mm(2) for DCE-MRI and US, respectively, P=0.859). The correlation with the histopathological major tumour diameter was 0.824 (P<0.001) and 0.705 (P<0.001) for post-treatment DCE-MRI and US, respectively. Measurements of the final major tumour diameter by DCE-MRI tended to be more precise, including cases achieving a pathological complete response. Randomized trials are warranted to establish the clinical impact of the initial discrepancy in tumour size estimates between DCE-MRI and US, and the trend towards a better definition of the final tumour size provided by DCE-MRI in this clinical setting.

Usefulness of three-dimensional multidetector-row CT images for preoperative evaluation of tumor extension in primary breast cancer patients

PURPOSE

Usefulness of three dimensional (3D) multidetector-row CT (MDCT) images for preoperative evaluation of tumor extension was studied in primary breast cancer patients.

METHODS

3D-MDCT tumor images of 143 tumors in 143 patients with primary breast cancer were created with the volume rendering method. The transverse tumor size (TS) and vertical tumor size (VS) were then measured in an anterior-posterior view of the 3D-MDCT images. The pathological tumor size was determined according to a map of the tumor spread prepared by pathologists using multi-sliced (3-5 mm intervals) surgical specimens and compared with the tumor size on 3D-MDCT images.

RESULTS

First, the optimal method for creating 3D-MDCT tumor images was determined for the first 40 patients (learning set), resulting in a fairly good correlation of tumor size on 3D-MDCT images with pathological tumor size (r = 0.983 for TS and r = 0.958 for VS). We then carried out a validation study on the next 103 patients (validation set). The 3D-MDCT tumor size's strong correlation with the pathological tumor size demonstrated a high rate of accuracy (r = 0.974 for TS and r = 0.977 for VS). Subset analyses according to histological type showed that correlation coefficients were r = 0.979 for TS and r = 0.981 for VS of invasive ductal carcinomas (n = 88), r = 0.948 for TS and r = 0.970 for VS of ductal carcinomas in situ (n = 10), and r = 0.984 for TS and r = 0.976 for VS of invasive lobular carcinomas (n = 5).

CONCLUSION

3D-MDCT images can assess breast cancer tumor extension highly accurately, and thus seems to be useful for planning the extent of resection in breast conserving surgery.

Multidetector row computed tomography for diagnosing intraductal extension of breast carcinoma

OBJECTIVES

Several reports supported the association of higher ipsilateral breast tumor recurrence rates with positive or intermediate margins compared with negative pathologic margins. Precise evaluation of intraductal component and adequate surgical margin are important factors affecting the tumor recurrence after breast conserving surgery. Numerous studies have reported the utility of magnetic resonance imaging for diagnosing developing intraductal extension of breast cancer, but few have investigated multidetector-row computed tomography (MD-CT). The present study evaluated the clinical utility of MD-CT for detecting intraductal extension of breast carcinoma, and analyzed clinical parameters affecting the detection of intraductal extension under MD-CT.

METHODS

Subjects comprised 44 patients grouped into three categories according to degree of intraductal extension of the main tumor under MD-CT (Intraductal spread grade 1 approximately 3: IDS 1 approximately 3). Tumors were also categorized histopathologically (p-IDS 0 approximately 3), and CT-pathological correlations were examined retrospectively. Clinical parameters were evaluated to determine the affect on detection of intraductal components.

RESULTS

MD-CT detected 44 breast lesions (100%). Sensitivity for detection of intraductal component was 81.2%, specificity was 67.8%, and accuracy was 72.7%. Regarding extent of intraductal components, significant correlations were found between histopathological and MD-CT findings. A strong correlation was found in postmenopausal women between T2 tumor and high histological grade.

CONCLUSIONS

MD-CT findings of intraductal extension from breast carcinoma correlate with histological degree of intraductal extension, and MD-CT may be useful for preoperative assessment of breast-conserving surgery, particularly for postmenopausal women with histological high nuclear grade and T2 tumor.

Relationship between tumour growth rate and carbogen-based functional MRI for a chemically induced HCC in mice

We previously performed MRI studies of HCC (hepatocellular carcinomas) in mice showing the feasibility of measuring a carbogen effect. In the present study carbogen response of the whole tumour was compared with growth characteristics during longitudinal follow-up. HCC were chemically induced. The imaging protocol at 4.7 T comprised a fast spin-echo sequence for high-resolution screening and measurement of growth curves, and a fast gradient echo sequence allowing an entire T2*w image acquisition per respiratory cycle to perform fMRI under carbogen breathing. A new parameter, T+, the fraction of tumour voxels with increased intensity under carbogen was measured on manually defined ROIs. Twenty-two HCC were followed for 3-10 weeks. Tumours were divided into two groups, "regularly" and "irregularly" growing tumours. A linear correlation between T+ and tumour growth rate was observed only for "regularly" growing HCC. These results suggest a link between tumour growth rates and tumour fractions exhibiting signal increase upon carbogen breathing. They are compatible with observations by others that rapidly growing tumours are more hypoxic than slowly growing ones. Combined measurement of T+ and tumour growth may become a useful noninvasive follow-up approach for assessment and/or management of therapies involving vasculature-targeting and anti-proliferative drugs.

The choice of the correct imaging modality in breast cancer management

This brief overview discusses which of the diagnostic options are more reliable and effective for breast cancer imaging with a view to avoiding the unjustified use of techniques that are suboptimal. The technological development of diagnostic imaging has been very impressive, and both radiological (mammography, ultrasonography, computed tomography, magnetic resonance imaging) and nuclear medicine tools (bone scan, planar and SPECT scintigraphy, sentinel node biopsy, positron emission tomography) have helped to overcome past limitations in the detection of small lesions. Furthermore, new approaches have been developed that permit successful differential diagnosis of doubtful lesions and rapid identification of systemic metastases, and allow non-invasive characterisation of the biology of cancer tissue. There is evidence that these advances may have helped in optimising therapeutic strategies. Importantly, the metabolic information provided by nuclear medicine procedures may be combined with the anatomical data supplied by radiological techniques in order to assist in predicting tumour response, planning radiotherapy and monitoring patient outcome. It is difficult to formulate conclusive diagnostic guidelines for application in the work-up of breast cancer, because while the role of some examinations, such as mammography and ultrasonography, is well established, that of others, such as magnetic resonance imaging and positron emission tomography, is still a matter of debate. There is a need for further prospective evaluations with appropriate clinical trials designed to evaluate the impact of these approaches in improving survival and quality of life.