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

Usefulness of four-dimensional noise reduction filtering using a similarity algorithm in low-dose dynamic computed tomography for the evaluation of breast cancer: a preliminary study

PURPOSE

To evaluate the effects of four-dimensional noise reduction filtering using a similarity algorithm (4D-SF) on the image quality and tumor visibility of low-dose dynamic computed tomography (CT) in evaluating breast cancer.

MATERIALS AND METHODS

Thirty-four patients with 38 lesions who underwent low-dose dynamic breast CT and were pathologically diagnosed with breast cancer were enrolled. Dynamic CT images were reconstructed using iterative reconstruction alone or in combination with 4D-SF. We selected the peak enhancement phase image of breast cancer for each patient for quantitative and qualitative evaluations of image quality and measurement of the maximum diameter of breast cancer. The signal-to-noise and contrast-to-noise ratios were calculated for quantitative evaluation. The maximum diameters of the breast cancer were measured from the images obtained with and without 4D-SF (4D-SF ±) (size-4D-SF + and size-4D-SF-) and for the pathological specimen (size-PS) and compared.

RESULTS

The median and interquartile ranges of the signal-to-noise ratio [4D-SF-: 3.03 (2.54-4.17) vs 4D-SF + : 5.52 (4.75-6.66)] and contrast-to-noise ratio [4D-SF-: 2.88 (2.00-3.60) vs 4D-SF + : 7.84 (4.65-10.35)] were significantly higher for 4D-SF + than for 4D-SF- (p < 0.001). The overall image quality (Observer 1, p < 0.001; Observer 2, p < 0.001) and tumor margin sharpness scores (Observer 1, p = 0.003; Observer 2, p < 0.001) were significantly higher for 4D-SF + than for 4D-SF-. The tumor contrast scores for 4D-SF + and 4D-SF- were not significantly different (Observers 1, 2; p = 0.083). Size-4D-SF- was significantly smaller than size-PS (p < 0.001); size-4D-SF + was also smaller than size-PS, but the difference was not significant (p = 0.088). The Spearman's rank correlation coefficient was 0.65 for size-PS and size-4D-SF- and 0.77 for size-PS and size-4D-SF + .

CONCLUSION

The 4D-SF can improve the image quality and tumor visibility of low-dose dynamic CT in evaluating breast cancer extent due to noise reduction.

Virtual monochromatic spectral CT imaging in preoperative evaluations for intraductal spread of breast cancer: comparison with conventional CT and MRI

PURPOSE

To investigate the efficacy of virtual monochromatic spectral computed tomography imaging (VMI) in the preoperative evaluation for intraductal spread of breast cancer.

MATERIALS AND METHODS

Twenty-four women who underwent spectral CT and were pathologically diagnosed with ductal carcinoma with a ≥ 2-cm noninvasive component were retrospectively enrolled in Group 1. Twenty-two women with 22 lesions pathologically diagnosed with ductal carcinoma in situ or microinvasive carcinoma were enrolled in Group 2. We compared the contrast-to-noise ratios (CNRs) of the lesions on conventional 120-kVp CT images and 40-keV VMIs in Group 1. Two board-certified radiologists measured the maximum diameters of enhancing areas on 120-kVp CT, 40-keV VMI, and MRI in Group 2 and compared with histopathological sizes.

RESULTS

The quantitative assessment of Group 1 revealed that the mean ± SD of the CNRs in the 40-keV images were significantly greater than those in the 120-kVp images (5.5 ± 1.9 vs. 3.6 ± 1.5, p < 0.0001). The quantitative assessment of Group 2 demonstrated that the lesion size observed in the conventional 120-kVp CT images by both readers was significantly underestimated as compared to the histopathological size (p = 0.017, 0.048), whereas both readers identified no significant differences between the lesion size measured on 40-keV VMI and the histopathological data. In a comparison with MRI, 40-keV VMI provided measurement within a 10-mm error range in more lesions as compared to the conventional 120-kVp CT.

CONCLUSION

VMI improves the evaluation of intraductal spread and is useful for the preoperative evaluations of breast cancer.

Iodinated Contrast Enhancement of Breast Cancer on Prone Multidetector Computed Tomography-Preliminary Findings

OBJECTIVES

Contrast-enhanced breast imaging has gained increasing importance in the diagnosis and management of breast cancer. The aim of this study was to assess breast cancer enhancement after contrast administration on prone multidetector computed tomography (MDCT).

MATERIALS AND METHODS

This retrospective, unicentric, institutional review board-approved study included patients with newly diagnosed breast cancer who were submitted to contrast-enhanced MDCT in prone position, with image acquisition before and after nonionic iodinated contrast administration.

RESULTS

Sixty breast cancer patients aged between 31 and 74 years (mean, 49 years) were included. Most patients (n = 50, 83.3%) had no special type invasive breast carcinoma and luminal subtype (n = 45, 75%). All index breast tumors were identified on prone MDCT. Forty-three cases (70.5%) presented as mass, 13 (21.3%) as nonmass enhancement and 4 (6.6%) as both mass and nonmass enhancement. Mean tumor density was 37.8 HU and 87.9 HU on precontrast and postcontrast images, respectively. Mean contrast enhancement was 50.2 HU (range, 20-109 HU). There were no statistically significant differences in tumor enhancement according to histological type, molecular subtype, nuclear grade, tumor size, or imaging presentation.

CONCLUSIONS

Our results show that breast cancer usually can be identified and have significant contrast enhancement on prone MDCT images. This method could be used as an alternative when other contrast-enhanced breast imaging methods are not available.

Multi-detector CT chest: can it omit the further need for contrast enhnaced spectral mammography in breast cancer patients candidate for CT staging?

Background

During multi-detector computed tomography (MDCT) of the chest, incidental breast lesions (IBLs) are occasionally encountered. Mammography remains the gold standard for the early detection of breast cancer. However, limitations exist in patients with dense breasts. Contrast spectral mammography (CESM) is widely available compared to MRI; it increases the sensitivity for breast cancer detection without decreasing the specificity.

Results

The study is a prospective study that included 113 female breast cancer patients for CT staging. One hundred and six of the patients had unilateral carcinoma and 7 of them had bilateral cancer with a total of 120 breasts evaluated. The CT findings were correlated with CESM findings regarding the multiplicity and bilaterality of the disease. The sensitivity, specificity, PPV, NPV, and accuracy of the CT in the detection of multiplicity were 97.44%, 100%, 100%, 95.45%, and 98.33%, respectively, and the sensitivity, specificity, PPV, NPV, and accuracy of the CT in the detection of bilateral disease were 68.18%, 97.96%, 88.24%, 93.20%, and 92.50%, respectively.

Conclusions

Breast cancer patients for MDCT chest as a part of their metastatic workup can omit the further need for CESM.

Subjective and Objective Assessment of Monoenergetic and Polyenergetic Images Acquired by Dual-Energy CT in Breast Cancer

Objective

To objectively and subjectively assess and compare the characteristics of monoenergetic images [MEI (+)] and polyenergetic images (PEI) acquired by dual-energy CT (DECT) of patients with breast cancer.

Materials and Methods

This retrospective study evaluated the images and data of 42 patients with breast cancer who had undergone dual-phase contrast-enhanced DECT from June to September 2019. One standard PEI, five MEI (+) in 10-kiloelectron volt (keV) intervals (range, 40–80 keV), iodine density (ID) maps, iodine overlay images, and Z effective (Z_eff) maps were reconstructed. The contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) were calculated. Multiple quantitative parameters of the malignant breast lesions were compared between the arterial and the venous phase images. Two readers independently assessed lesion conspicuity and performed a morphology analysis.

Results

Low keV MEI (+) at 40–50 keV showed increased CNR and SNR_{breast lesion} compared with PEI, especially in the venous phase ([CNR: 40 keV, 20.10; 50 keV, 14.45; vs. PEI, 7.27; p < 0.001], [SNR_{breast lesion}: 40 keV, 21.01; 50 keV, 16.28; vs. PEI, 10.77; p < 0.001]). Multiple quantitative DECT parameters of malignant breast lesions were higher in the venous phase images than in the arterial phase images (p < 0.001). MEI (+) at 40 keV, ID, and Z_eff reconstructions yielded the highest Likert scores for lesion conspicuity. The conspicuity of the mass margin and the visual enhancement were significantly better in 40-keV MEI (+) than in the PEI (p = 0.022, p = 0.033, respectively).

Conclusion

Compared with PEI, MEI (+) reconstructions at low keV in the venous phase acquired by DECT improved the objective and subjective assessment of lesion conspicuity in patients with malignant breast lesions. MEI (+) reconstruction acquired by DECT may be helpful for the preoperative evaluation of breast cancer.

Utility of 70-kV single-energy CT in depicting the extent of breast cancer for preoperative planning

PURPOSE

To evaluate the detectability of breast cancer and visibility of the tumor extent using 70-kV single-energy contrast-enhanced (CE) breast computed tomography (70-kV CECT) compared with CE breast magnetic resonance imaging (CEMR).

METHODS

Between 2013 and 2015, 110 patients with 112 breast cancer lesions who underwent breast surgery after undergoing both 70-kV CECT and CEMR were enrolled. The major axis lengths of the breast lesion were measured and compared with the pathologically determined major axes. Agreement in the measured major axes was evaluated using the intra-class correlation coefficient (ICC).

RESULTS

Both 70-kV CECT and CEMR depicted all breast cancer lesions. The mean major axis was 3.0 (95% confidence interval [CI], 2.5-3.4) cm on CECT and 2.9 (2.6-3.3) cm on CEMR. The mean differences between the pathologically and radiologically measured major axes on 70-kV CECT and CEMR were 0.9 (0.7-1.1) and 1.0 (0.8-1.2) cm, respectively. The accuracy of the radiological major axes compared with the pathological major axes was 82.1% and 80.4% on CECT and CEMR, respectively (p = 0.81). The major axes on the two modalities demonstrated moderate agreement (ICC = 0.69, 95% CI 0.58-0.77). Pathologically and radiologically measured major axes on 70-kV CECT and CEMR demonstrated excellent agreement (ICC = 0.91, 95% CI 0.93-0.96).

CONCLUSIONS

Low-tube voltage (70-kV) CECT is the preferred modality to identify breast cancer lesions and tumor extent for preoperative planning because it has a similar diagnostic ability to CEMR and can be performed in the supine position.

Multidetector Computed Tomography with Dedicated Protocol for Breast Cancer Locoregional Staging: Feasibility Study

BACKGROUND

The aim of this study was to demonstrate the feasibility of performing multidetector computed tomography (MDCT) with a dedicated protocol for locoregional staging in breast cancer patients.

METHODS

This prospective single-center study included newly diagnosed breast cancer patients submitted to contrast-enhanced chest MDCT and breast magnetic resonance imaging (MRI). MDCT was performed in prone position and using subtraction techniques. Fleiss' Kappa coefficient (K) and intraclass correlation coefficient (ICC) were used to assess agreement between MRI, MDCT, and pathology, when available.

RESULTS

Thirty-three patients were included (mean age: 47 years). Breast MRI and MDCT showed at least substantial agreement for evaluation of tumor extension (k = 0.674), presence of multifocality (k = 0.669), multicentricity (k = 0.857), nipple invasion (k = 1.000), skin invasion (k = 0.872), and suspicious level I axillary lymph nodes (k = 0.613). MDCT showed higher number of suspicious axillary lymph nodes than MRI, especially on levels II and III. Both methods had similar correlation with tumor size (MRI ICC: 0.807; p = 0.008 vs. MDCT ICC: 0.750; p = 0.020) and T staging (k = 0.699) on pathology.

CONCLUSIONS

MDCT with dedicated breast protocol is feasible and showed substantial agreement with MRI features in stage II or III breast cancer patients. This method could potentially allow one-step locoregional and systemic staging, reducing costs and improving logistics for these patients.

Dual-energy computed tomography for evaluation of breast cancer: value of virtual monoenergetic images reconstructed with a noise-reduced monoenergetic reconstruction algorithm

PURPOSE

To evaluate the image quality and lesion visibility of virtual monoenergetic images (VMIs) reconstructed using a new monoenergetic reconstruction algorithm (nMERA) for evaluation of breast cancer.

MATERIALS AND METHODS

Forty-two patients with 46 breast cancers who underwent 4-phasic breast contrast-enhanced computed tomography (CT) using dual-energy CT (DECT) were enrolled. We selected the peak enhancement phase of the lesion in each patient. The selected phase images were generated by 120-kVp-equivalent linear blended (M120) and monoenergetic reconstructions from 40 to 80 keV using the standard reconstruction algorithm (sMERA: 40, 50, 60, 70, 80) and nMERA (40 +, 50 +, 60 +, 70 +, 80 +). The contrast-to-noise ratio (CNR) was calculated and objectively analyzed. Two independent readers subjectively scored tumor visibility and image quality each on a 5-point scale.

RESULTS

The CNR at 40 + and tumor visibility scores at 40 + and 50 + were significantly higher than those on M120. The CNR at 50 + was not significantly different from that on M120. However, the overall image quality score at 40 + was significantly lower than that at 50 + and on M120 (40 + vs M120, P < 0.0001 and 40 + vs 50 +, P = 0.0001).

CONCLUSIONS

VMI reconstructed with nMERA at 50 keV is preferable for evaluation of patients with breast cancer.

Mammography, US, and MRI to Assess Outcomes of Invasive Breast Cancer with Extensive Intraductal Component: A Matched Cohort Study

Background An extensive intraductal component (EIC) in breast cancer is an independent risk factor for local recurrence after surgery, especially in young, premenopausal women. Few studies have analyzed long-term outcomes or imaging features of EIC-positive breast cancer. Purpose To assess the prognostic value of EIC on recurrence-free and overall survival in breast cancer and evaluate imaging features of EIC-positive breast cancer by using mammography, US, and MRI. Materials and Methods A retrospective study of 6816 consecutive women with surgically diagnosed invasive breast cancer between January 2007 and December 2012 was performed. After individual matching, women were allocated into either an EIC-positive or an EIC-negative group. Imaging factors associated with prognosis were investigated. The recurrence-free and overall survival rates were compared. Univariable and multivariable analyses were performed to analyze the effect of EIC. Results Among 6136 included women (mean age, 48.9 years ± 9.8), 1800 EIC-positive and 4336 EIC-negative breast cancers were identified. After matching according to EIC presence was performed, 1551 women were allocated into each group. The mean follow-up period was 79.9 months. The local-regional recurrence rate in the EIC-positive group was higher than that in the EIC-negative group (39.4% [63 of 160] vs 25.5% [37 of 145]; P = .001). However, there were no significant differences in total recurrence rate (hazard ratio [HR]: 1.2; 95% confidence interval [CI]: 0.9, 1.4; P = .21) or death (HR: 1.1; 95% CI: 0.8, 1.5; P = .45). EIC was not a significant independent factor for recurrence-free survival (HR: 1.1; 95% CI: 0.9, 1.4; P = .45) or death (HR: 1.1; 95% CI: 0.8, 1.6; P = .44) in multivariable analyses. Calcification and non-mass lesions were more commonly seen at US and MRI in the EIC-positive group than in the EIC-negative group (P < .001). Conclusion The presence of an extensive intraductal component in women with invasive breast cancer did not affect overall survival or recurrence-free survival. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Eby in this issue.

Diagnostic imaging strategy for MDCT- or MRI-detected breast lesions: use of targeted sonography

BACKGROUND

Leading-edge technology such as magnetic resonance imaging (MRI) or computed tomography (CT) often reveals mammographically and ultrasonographically occult lesions. MRI is a well-documented, effective tool to evaluate these lesions; however, the detection rate of targeted sonography varies for MRI detected lesions, and its significance is not well established in diagnostic strategy of MRI detected lesions. We assessed the utility of targeted sonography for multidetector-row CT (MDCT)- or MRI-detected lesions in practice.

METHODS

We retrospectively reviewed 695 patients with newly diagnosed breast cancer who were candidates for breast conserving surgery and underwent MDCT or MRI in our hospital between January 2004 and March 2011. Targeted sonography was performed in all MDCT- or MRI-detected lesions followed by imaging-guided biopsy. Patient background, histopathology features and the sizes of the lesions were compared among benign, malignant and follow-up groups.

RESULTS

Of the 695 patients, 61 lesions in 56 patients were detected by MDCT or MRI. The MDCT- or MRI-detected lesions were identified by targeted sonography in 58 out of 61 lesions (95.1%). Patients with pathological diagnoses were significantly older and more likely to be postmenopausal than the follow-up patients. Pathological diagnosis proved to be benign in 20 cases and malignant in 25. The remaining 16 lesions have been followed up.Lesion size and shape were not significantly different among the benign, malignant and follow-up groups.

CONCLUSIONS

Approximately 95% of MDCT- or MRI-detected lesions were identified by targeted sonography, and nearly half of these lesions were pathologically proven malignancies in this study. Targeted sonography is a useful modality for MDCT- or MRI-detected breast lesions.

Preoperative CT evaluation of intraductal spread of breast cancer and surgical treatment

It is always a challenge to accurately determine the appropriate extent of resection in breast-conserving surgery (BCS), in order to reduce the need for re-excision, prevent local recurrence, and optimize cosmetic results. Detecting intraductal spread alone with high sensitivity may not be enough to realize safe BCS. Computed tomography carried out with the patient in the supine position accompanied by adequate marking is effective for preoperative determination of the optimum extent of BCS.

High-frequency ultrasound for intraoperative margin assessments in breast conservation surgery: a feasibility study

Background

In addition to breast imaging, ultrasound offers the potential for characterizing and distinguishing between benign and malignant breast tissues due to their different microstructures and material properties. The aim of this study was to determine if high-frequency ultrasound (20-80 MHz) can provide pathology sensitive measurements for the ex vivo detection of cancer in margins during breast conservation surgery.

Methods

Ultrasonic tests were performed on resected margins and other tissues obtained from 17 patients, resulting in 34 specimens that were classified into 15 pathology categories. Pulse-echo and through-transmission measurements were acquired from a total of 57 sites on the specimens using two single-element 50-MHz transducers. Ultrasonic attenuation and sound speed were obtained from time-domain waveforms. The waveforms were further processed with fast Fourier transforms to provide ultrasonic spectra and cepstra. The ultrasonic measurements and pathology types were analyzed for correlations. The specimens were additionally re-classified into five pathology types to determine specificity and sensitivity values.

Results

The density of peaks in the ultrasonic spectra, a measure of spectral structure, showed significantly higher values for carcinomas and precancerous pathologies such as atypical ductal hyperplasia than for normal tissue. The slopes of the cepstra for non-malignant pathologies displayed significantly greater values that differentiated them from the normal and malignant tissues. The attenuation coefficients were sensitive to fat necrosis, fibroadenoma, and invasive lobular carcinoma. Specificities and sensitivities for differentiating pathologies from normal tissue were 100% and 86% for lobular carcinomas, 100% and 74% for ductal carcinomas, 80% and 82% for benign pathologies, and 80% and 100% for fat necrosis and adenomas. Specificities and sensitivities were also determined for differentiating each pathology type from the other four using a multivariate analysis. The results yielded specificities and sensitivities of 85% and 86% for lobular carcinomas, 85% and 74% for ductal carcinomas, 100% and 61% for benign pathologies, 84% and 100% for fat necrosis and adenomas, and 98% and 80% for normal tissue.

Conclusions

Results from high-frequency ultrasonic measurements of human breast tissue specimens indicate that characteristics in the ultrasonic attenuation, spectra, and cepstra can be used to differentiate between normal, benign, and malignant breast pathologies.

Intracystic Papillary Carcinoma of the Breast in Males. In Search of the Optimal Treatment for this Rare Disease

Intracystic papillary carcinoma (IPC) of the breast in men is an extremely infrequent disease, and it appears to have a good prognosis. Because of this, histological findings are of great importance in the decision-making process regarding treatment. Clinical examination, radiological and histological assessments are required for early detection. Adequate surgical excision with negative margins is mandatory. However, the role of sentinel node biopsy has not been evaluated in male IPC. It appears that sentinel node biopsy may be an excellent alternative to radical axillary dissection in patients with IPC and associated ductal carcinoma in situ or invasive carcinoma. Nevertheless, due to the rarity of IPC and its confusing histopathological classification and staging, there are still no clear guidelines as far as IPC treatment is concerned.

Radiologic-pathologic correlation of ductal carcinoma in situ

Ductal carcinoma in situ (DCIS) accounts for 20%-25% of breast cancers detected at screening mammography. The lesions are diverse and commonly are classified on the basis of their mammographic features and histologic characteristics such as nuclear grade and presence or absence of necrosis. The most common mammographic finding in DCIS is microcalcifications, but a low-grade lesion without necrosis is less likely to manifest with calcifications than either an intermediate- or a high-grade lesion. Other mammographic findings might include a mass or architectural distortion. Magnetic resonance (MR) imaging has higher sensitivity than mammography for the detection of DCIS and greater accuracy for depicting the extent of disease. The MR imaging appearance of DCIS depends primarily on the presence and extent of abnormal periductal or stromal vascularity. Nonmasslike enhancement, the most common MR imaging finding, is often seen in association with clumped internal enhancement. The enhancement kinetics in dynamic MR studies vary, and no kinetic pattern is pathognomonic of a particular nuclear grade of DCIS. However, the kinetic pattern at delayed imaging does appear to be correlated with the mammographic findings: Mass lesions show strong washout; fine pleomorphic, fine linear, and fine linear-branching calcifications demonstrate a plateau enhancement pattern; and amorphous calcifications exhibit persistent enhancement. Multidetector computed tomography might be a useful adjunct to MR imaging for preoperative mapping.

Successful use of multi-detector row computed tomography for detecting contralateral breast cancer

OBJECTIVE

We retrospectively evaluated whether multi-detector row computed tomography (MDCT) could contribute to the early detection of contralateral breast cancer in women with a diagnosis of breast cancer and no suspicious lesions on a mammogram or an ultrasonogram of the contralateral breast.

METHODS

A total of 518 women with newly diagnosed unilateral breast cancer underwent MDCT. Multi-detector row CT was performed using a 16-detector row CT scanner set for 2-mm collimation, 120 kilovolt (peak), and 180 mA. Axial images of the contralateral breast were evaluated.

RESULTS

Four hundred fifty-nine women were eligible for this study. There were suspicious malignant lesions only on MDCT in 21. Multi-detector row CT contributed to the diagnosis of contralateral occult breast cancer in 12 women (2.6%), including 1 in whom breast cancer was later diagnosed at another institution.

CONCLUSIONS

Multi-detector row CT has a potential role in detecting contralateral breast cancer in women who are at high risk.

Diagnosis of breast cancer with multidetector computed tomography: analysis of optimal delay time after contrast media injection

PURPOSE

The aim of this study was to investigate the optimal delay time after a contrast media injection for multidetector computed tomography (MD-CT) images in the diagnosis of breast cancer patients.

MATERIALS AND METHODS

Thirty-one patients who underwent MD-CT for their preoperative examination and who had postoperatively confirmed pathology were enrolled. Four-phase images of dynamic contrast enhanced study were acquired using four-detector MDCT. All cases were mammographically classified into two groups according to BI-RADS: nondense and dense groups. The CT value of the background mammary gland, background breast enhancement (BBE), and tumor-background mammary gland contrast (TBC) were compared between the two groups.

RESULTS

The CT value of the dense group was significantly higher than that of the nondense group in all phases. BBE in both nondense and dense groups showed no significant differences in any of the phases. In the nondense group, TBC was significantly higher in both the second and the third phases than in the first phase, while in the dense group, TBC was significantly higher in the second phase than in the first and third phases.

CONCLUSION

The optimal delay time to depict breast cancer is 80 s after a contrast media injection, regardless of the density level of the background mammary gland.

Real-time 3-dimensional virtual reality navigation system with open MRI for breast-conserving surgery

BACKGROUND

The aim of this study was to report on the early experiences using a real-time 3-dimensional (3D) virtual reality navigation system with open MRI for breast-conserving surgery.

STUDY DESIGN

We developed a real-time 3D virtual reality navigation system with open MRI, and evaluated the mismatch between the navigation system and real distance using a 3D phantom. Two patients with nonpalpable MRI-detected breast tumors underwent breast-conserving surgery under the guidance of the navigation system. An initial MRI for the breast tumor using skin-affixed markers was performed immediately before excision. A percutaneous intramammary dye marker was applied to delineate an excision line, and the computer software "3D Slicer" generated a real-time 3D virtual reality model of the tumor and the puncture needle in the breast. Excision of the tumor was performed in the usual manner along the excision line indicated with the dye. The resected specimens were carefully examined histopathologically.

RESULTS

The mean mismatch between the navigation system and real distance was 2.01 +/- 0.32 mm when evaluated with the 3D phantom. Under guidance by the navigation system, a percutaneous intramammary dye marker was applied without any difficulty. Fiducial registration errors were 3.00 mm for patient no. 1, and 4.07 mm for patient no. 2. Histopathological examinations of the resected specimens of the 2 patients showed noninvasive ductal carcinoma in situ. The surgical margins were free of carcinoma cells.

CONCLUSIONS

Real-time 3D virtual reality navigation system with open MRI is feasible for safe and accurate excision of nonpalpable MRI-detected breast tumors. Long-term outcomes of this technique should be evaluated further.

Fusion of MRI and sonography image for breast cancer evaluation using real-time virtual sonography with magnetic navigation: first experience

OBJECTIVE

We recently developed a real-time virtual sonography (RVS) system that enables simultaneous display of both sonography and magnetic resonance imaging (MRI) cutaway images of the same site in real time. The aim of this study was to evaluate the role of RVS in the management of enhancing lesions visualized with MRI.

METHODS

Between June 2006 and April 2007, 65 patients underwent MRI for staging of known breast cancer at our hospital. All patients were examined using mammography, sonography, MRI and RVS before surgical resection. Results were correlated with histopathologic findings. MRI was obtained on a 1.5 T imager, with the patient in the supine position using a flexible body surface coil. Detection rate was determined for index tumors and incidental enhancing lesions (IELs), with or without RVS.

RESULTS

Overall sensitivity for detecting index tumors was 85% (55/65) for mammography, 91% (59/65) for sonography, 97% (63/65) for MRI and 98% (64/65) for RVS. Notably, in one instance in which the cancer was not seen on MRI, RVS detected it with the supplementation of sonography. IELs were found in 26% (17/65) of the patients. Of 23 IELs that were detected by MRI, 30% (7/23) of IELs could be identified on repeated sonography alone, but 83% (19/23) of them were identified using the RVS system (P = 0.001). The RVS system was able to correctly project enhanced MRI information onto a body surface, as we checked sonography form images.

CONCLUSIONS

Our results suggest that the RVS system can identify enhancing breast lesions with excellent accuracy.

Magnetic resonance imaging of ductal carcinoma in situ: what is its clinical application? A review

BACKGROUND

After breast-conserving surgery of ductal carcinoma in situ (DCIS) of the breast or invasive breast carcinoma with an extensive intraductal component, tumor-positive surgical margins are frequently found. Therefore, the extent of the intraductal disease needs to be accurately determined preoperatively.

METHODS

Data for this review were identified by search of PubMed. Reference lists of selected articles were cross-searched for additional literature.

RESULTS

DCIS is accurately detected with magnetic resonance imaging (MRI), but the typical malignant features are inconsistently seen and most often in high-grade DCIS or in DCIS with a small invasive component. The histopathologic extent of DCIS is more accurately demonstrated with MRI. However, overestimation due to benign proliferative lesions does frequently occur. An improved depiction of DCIS could lead to improved preoperative staging. Conversely, the identification of more extensive disease on MRI could give rise to unnecessary interventions. Therefore, MRI should be used carefully and preferable in specialized and experienced centers.

CONCLUSION

[corrected] To date, there is no evidence that the use of MRI improves outcomes (ie, decreases recurrence rates) in patients with DCIS.

Magnetic resonance imaging in size assessment of invasive breast carcinoma with an extensive intraductal component

Background

Breast-conserving treatment of invasive breast carcinoma with an extensive intraductal component (EIC) is associated with DCIS-involved surgical margins and therefore it has an increased recurrence rate. EIC is a non-palpable lesion of which the size is frequently underestimated on mammography. This study was undertaken to evaluate the accuracy of MRI in size assessment of breast cancer with EIC.

Methods

23 patients were identified and the mammographic (n = 21) and MR (n = 23) images were re-reviewed by a senior radiologist. Size on MR images was compared with histopathological tumour extent.

Results

The correlation of radiological size with histopathological size was r = 0.20 in mammography (p = 0.39) compared to r = 0.65 in MRI (p < 0.01). Mammography underestimated histopathological tumour size in 62%. MR images over- or underestimated tumour size in 22% and 30% of the cases, respectively. In poorly differentiated EIC, MRI adequately estimated the extent more often compared to moderately differentiated EIC (60% versus 25%, respectively).

Conclusion

Size assessment of MRI imaging was more accurate compared to mammography. This was predominantly true for poorly differentiated EIC.

Diagnosis of breast cancer: MDCT versus MRI

In Japan, helical CT has been applied to breast cancers for the accurate determination of cancer extent before surgery. In recent years, multidetector CT (MDCT) has become commercially available. Compared with mammography and ultrasonography, MDCT of the breast is thought to be useful for preoperative assessment of breast-conserving surgery. In contrast, magnetic resonance imaging (MRI) is extremely accurate in the diagnosis of intraductal carcinoma and multicentricity of breast cancer. A real problem related to the use of CT is X-ray exposure. Therefore, it is controversial whether the use of CT for the patients with breast cancer is appropriate or not. Recent studies that compared the use of MDCT and MRI in the same patients concluded that MRI was more accurate for the detection and evaluation of the extent of intraductal carcinoma. We should consider the pitfalls and limitations of CT for assessing the breast cancer extent.

Usefulness of lesion image mapping with multidetector-row helical computed tomography using a dedicated skin marker in breast-conserving surgery

To investigate the usefulness of computed tomography (CT) with skin-marker placement in determining the excision area and decreasing the positive or close margin rates in breast-conserving surgery (BCS). Multidetector-row helical computed tomography (MDCT) mapping images were reconstructed in subjects (n = 117) diagnosed with primary breast cancer who had undergone MDCT using CT skin markers. Serial 5-mm-thick slices prepared from the surgical specimen were used for pathological analyses. A "positive margin" was defined as the presence of malignant cells at the surgical margin, and a "close margin" as a tumor within 5 mm of the surgical margin. The rates of positive and close margins were calculated. We identified the lesions in 111 of 117 cases (94.9%) on MDCT. Of these, 93 underwent BCS under the guidance of MDCT mapping and the remaining 18 underwent mastectomy. Among the 93 cases, 6 (6.5%) had positive or close margins and were diagnosed with ductal carcinoma in situ of low nuclear grade. MDCT mapping with a CT skin marker is feasible for simulating surgical positioning and determining the excision area. MDCT mapping could decrease the positive and close margin rates in BCS.

Clinical application of multidetector row computed tomography in patient with breast cancer

Although multidetector row computed tomography is not the primary method of evaluating breast cancer, it could be performed as an excellent alternative, especially in the presence of magnetic resonance contraindications. Moreover, computed tomography can still have an important role in evaluation of nodal status, thoracic invasion, and distant metastasis because of the large area covered in a single examination. Our experience together with literature indicates that multidetector row computed tomography is a powerful supplementary method for evaluation of patients with breast cancer.

A case of intracystic papillary carcinoma accompanying widespread ductal carcinoma in situ

A 39-year-old Japanese woman noticed a right breast tumor in July 2004. Mammography (MMG) demonstrated an oval tumor without calcification. Dynamic Magnetic Resonance Imaging (D-MRI) demonstrated a high-intensity mass on T2-weighted images, showing mild enhancement during the arterial phase and persistent enhancement during the arterial late phase. Core needle biopsy revealed papillary carcinoma suggestive of Intracystic Papillary Carcinoma (IPC). Auchincloss operation was performed following a partial mastectomy, as the surgical margin after partial mastectomy was positive for carcinoma. Histopathologic mapping of her right breast revealed wide and extensive intraductal spread of DCIS around the IPC. IPC was originally reported to be a localized non-invasive mammary carcinoma. But approximately, half of IPC cases are associated with invasive carcinoma or DCIS beyond the tumor. Careful selection of operative procedure is needed after localized non-invasive IPC or IPC associated with DCIS around the main tumor or invasive carcinoma is diagnosed.

Breast CT

Breast cancer is a serious disease that accounts for approximately 40,000 deaths per year in the United States. Unfortunately, there is no known cause of breast cancer, and therefore the best way to prevent mortality is early detection. In the past 15 years, breast cancer mortality has been reduced significantly, which is in part due to screening with film-screen mammography. Nonetheless, conventional mammography lacks sensitivity, especially for certain subgroups of women such as those with dense breast tissue, those under 50 years old, and pre- or perimenopausal women. In addition, mammography has a very poor positive predictive value for biopsy, with 70%-90% of biopsies performed turning out negative. By improving visualization of breast tissue, X-ray computerized tomography (CT) of the breast can potentially provide improvements in diagnostic accuracy over conventional mammography. Owing to recent technological developments in digital detector technology, flat-panel CT imagers dedicated to imaging of the breast are now feasible. A number of academic groups are currently researching dedicated breast CT and prototype systems are currently being evaluated in the clinical setting.