Differentiating between benign and malignant breast lesions using dual-energy CT-based model: development and validation

OBJECTIVES

To develop and validate a dual-energy CT (DECT)-based model for noninvasively differentiating between benign and malignant breast lesions detected on DECT.

MATERIALS AND METHODS

This study prospectively enrolled patients with suspected breast cancer who underwent dual-phase contrast-enhanced DECT from July 2022 to July 2023. Breast lesions were randomly divided into the training and test cohorts at a ratio of 7:3. Clinical characteristics, DECT-based morphological features, and DECT quantitative parameters were collected. Univariate analyses and multivariate logistic regression were performed to determine independent predictors of benign and malignant breast lesions. An individualized model was constructed. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic ability of the model, whose calibration and clinical usefulness were assessed by calibration curve and decision curve analysis.

RESULTS

This study included 200 patients (mean age, 49.9 ± 11.9 years; age range, 22-83 years) with 222 breast lesions. Age, lesion shape, and the effective atomic number (Zeff) in the venous phase were significant independent predictors of breast lesions (all p < 0.05). The discriminative power of the model incorporating these three factors was high, with AUCs of 0.844 (95%CI 0.764-0.925) and 0.791 (95% CI 0.647-0.935) in the training and test cohorts, respectively. The constructed model showed a preferable fitting (all p > 0.05 by the Hosmer-Lemeshow test) and provided enhanced net benefits than simple default strategies within a wide range of threshold probabilities in both cohorts.

CONCLUSION

The DECT-based model showed a favorable diagnostic performance for noninvasive differentiation between benign and malignant breast lesions detected on DECT.

CRITICAL RELEVANCE STATEMENT

The combination of clinical and morphological characteristics and DECT-derived parameter have the potential to identify benign and malignant breast lesions and it may be useful for incidental breast lesions on DECT to decide if further work-up is needed.

KEY POINTS

It is important to characterize incidental breast lesions on DECT for patient management. DECT-based model can differentiate benign and malignant breast lesions with good performance. DECT-based model is a potential tool for distinguishing breast lesions detected on DECT.

Assignment of the biological value of solid breast masses based on quantitative evaluations of spectral CT examinations using electron density mapping, Zeffective mapping and iodine mapping

OBJECTIVE

We aimed to asses, in a clinical setting, whether the newly available quantitative evaluation of electron density (ED) in spectral CT examinations of the breast provide information on the biological identity of solid breast masses and whether ED maps yield added value to the diagnostic information of iodine maps and Zeff maps calculated from the same CT image datasets.

METHODS

All patients at the University Breast Cancer Center who underwent a clinically indicated Dual Layer Computed Tomography (DLCT) examination for staging of invasive breast cancer from 2018 to 2020 were prospectively included. Iodine concentration maps, Zeff maps and ED maps were automatically reconstructed from the DLCT datasets. Region of interest (ROI) based evaluations in the breast target lesions and in the aorta were performed semi-automatically in identical anatomical positions using dedicated evaluation software. Case-by-case evaluations were carried independently by 2 of 4 radiologists for each examination, respectively. Statistical analysis derived from the ROIs was done by calculating ROC/AUC curves and Youden indices.

RESULTS

The evaluations comprised 166 DLCT examinations. In the ED maps the measurements in the breast target lesions yielded Youden cutpoints of 104.0% (reader 1) and 103.8% (reader 2) resulting in AUCs of 0.63 and 0.67 at the empirical cutpoints. The variables "Zeff" and "iodine content" derived from the target lesions showed superior diagnostical results, with a Youden cutpoint of 8.0 mg/ml in the iodine maps and cutpoints of 1.1/1.2 in the Zeff maps the AUCs ranging from 0.84 to 0.85 (p = 0.023 to <0.000). The computational combination of Zeff and ED measurements in the target lesions yielded a slight AUC increase (readers 1: 0.85-0.87; readers 2: 0.84-0.94). The ratios of the measured values in the target lesions normalized to the values measured in the aorta showed comparable results. The AUCs of ED derived from the cutpoints showed inferior results to those derived from the Zeff maps and iodine maps (ED: 0.64 and 0.66 for reader 1 and 2; Zeff: 0.86 for both readers; iodine content: 0.89 and 0.86 for reader 1 and 2, respectively). The computational combination of the ED results and the Zeff measurements did not lead to a clinically relevant diagnostic gain with AUCs ranging from 0.86 to 0.88.

CONCLUSIONS

Quantitative assessments of Zeff, iodine content and ED all targeting the physical and chemical aspects of iodine uptake in solid breast masses confirmed diagnostically robust cutpoints for the differentiation of benign and malignant findings (Zeff < 7.7, iodine content of <0.8 mg/ml). The evaluations of the ED did not indicate any added diagnostic value beyond the quantitative assessments of Zeff and iodine content. Further research is warranted to develop suitable clinical indications for the use of ED maps.

Missed and Detected Incidental Breast Cancers on Contrast Enhanced Chest CT: Detection Rates and CT Features

This study investigated the rate at which radiologists miss or detect incidental breast cancers on chest CT and to compare the CT features between the two groups. This retrospective study evaluated chest CT examinations and medical records of patients who registered with the diagnosis code of "breast cancer" between January 2016 and December 2020, and who had undergone contrast enhanced chest CT 3-18 months before registration, during which they were unaware of any breast lesions. This study found that out of 84 patients, incidental breast cancer lesions were missed in 54 (64.3%) and detected in 30 (53.7%). The initial treatment was delayed in the missed breast lesions group (p = 0.004). Breast lesions of smaller sizes (<9.0 mm, p = 0.01), or with lower enhancement ratios (<1.4, p = 0.009), were more likely to be missed. When three radiologists re-read the CTs with more attention to breast area, they detected breast cancers with higher accuracies (90.1%, 87.9%, and 81.3%). In summary, this study revealed that radiologists miss 64.3% of incidental breast cancers on chest CT, especially those of sub-centimeter sizes and weak enhancements.

Correlation of CT-data derived from multiparametric dual-layer CT-maps with immunohistochemical biomarkers in invasive breast carcinomas

OBJECTIVE

To examine the correlation of quantitative measurements from material decomposition maps calculated from dual-layer CT (DLCT)-image datasets with immunohistochemical biomarkers of invasive breast carcinomas.

MATERIAL AND METHODS

All patients at the University Breast Cancer Center who underwent a clinically indicated dual-layer CT-scan for staging of invasive ductal breast carcinoma from 01/2016 to 07/2020 were prospectively included. Iodine concentration maps and maps of the effective atomic numbers (Zeffective) were reconstructed from the image datasets. ROI-based evaluations of the index tumors and predefined references tissues for normalization were performed semi-automatically in identical anatomical positions using dedicated evaluation software. Statistical analysis was essentially descriptive using Spearmańs rank correlation and (multivariable) partial correlation.

RESULTS

Bivariate showed statistically significant correlations of iodine contents (r = -0.154/-0.202/0.180, p = 0.039/0.006/0.015), and Zeffective-values (r = -0.158/-0.199/0.179, p = 0.034/0.007/0.016) for all 184 carcinomas and the subgroup of 168 invasive ductal carcinomas. The results were confirmed by multivariate analyses with "age", "diameter" and "ACR-grade" as possible confounders. Normalization of the measured target values with those in the aorta confirmed significant correlations of iodine content and Zeffective compared to Estrogen (r = 0.174, p = 0.019), Progesteron (r = 0.168/0.177, p = 0.024/0.017), and HER2 receptor expression (r = -0.222/-0.184, p = 0.003/0.013). All CT-parameters showed significant correlations with immunohistochemical subtyping (r = 0.191/0.192, p = 0.010).

CONCLUSIONS

Our preliminary results indicate that iodine content and Zeffective-values derived from DLCT-examinations correlate with hormone receptor expression in invasive breast carcinomas. Assignments to benign entities already seam feasible in clinical routine CT-diagnostics. After further investigations iodine content and Zeffective may be translated as diagnostical and prognostical biomarkers into clinical routine in the long term.

Chest calcifications beyond the lung parenchyma-A review

OBJECTIVE

Thoracic calcifications are frequently found in chest radiographs and CTs, occurring in a wide variety of disorders. Although most calcifications are harmless sequelae of previous disease, they provide important information to establish the diagnosis. This article reviews the different types of calcified lesions found in the chest, focusing on lesions outside the lung parenchyma. A location-based approach to the differential diagnosis is used, while providing the reader with diagnostic pearls and discussing the clinical importance of the different types of calcifications.

CONCLUSION

Chest calcifications are a common finding in routine chest imaging. Understanding the different etiologies and radiologic manifestations provide the radiologist with the necessary tools to elaborate a differential diagnosis, as well as to correctly differentiate the findings that need further work-up from the ones that can be dismissed.

Acute lymphoblastic leukemia simulating breast carcinoma

Background

Breast metastasis in hematological malignancies is a rare phenomenon, and it is primarily seen in acute myeloid leukemia (AML). In patients with acute lymphoblastic leukemia (ALL), this condition is even rarer.

Case presentation.

We present a case of a precursor B cell ALL involving breast in a 40-year-old female and its imaging features on mammography and ultrasound. Histopathology of core needle biopsy (CNB) specimen allowed us to diagnose ALL with extramedullary metastases. The patient was referred to oncology for further management.

Conclusion

To conclude, ALL infiltrating breast is rare but should be given due consideration, especially in the cases of known primary hematopoietic malignancy, particularly in patients presenting with a history of sudden lumps in the breast. A CNB can give reliable results in combination with flow cytometry and immunocytochemistry, circumventing the need for an excisional biopsy and allowing the commencement of early treatment.

Rare Papillary Breast Carcinoma Incidentally Discovered After Trauma-Induced Hematoma

Papillary carcinoma of the breast is rare, comprising only 0.5% incidence of all breast cancers. Clinically the disease presents in postmenopausal women as a painless breast lump with possible bloody nipple discharge. Prognosis is favorable due to its slow growth. We present a 61-year-old woman incidentally diagnosed with papillary breast carcinoma after presenting with a trauma-induced hematoma of the right breast. The patient presented to our surgery oncology clinic for persistent right breast swelling secondary to a fall, despite initial incision and drainage (I&D) six weeks prior. She had no history of breast cancer. On presentation, her right breast was distended demonstrating an approximately 20cm ill-defined solid mass with skin changes consistent with a tense hematoma. CT scan demonstrated a large complex cystic and solid breast mass measuring 15.2cmx11.8cmx15.2cm with irregular peripheral solid hyperdense polypoid components. She then underwent a right breast incisional biopsy and hematoma evacuation. Frozen sections of the mass outer cavity wall and papillary projections were consistent with encapsulated papillary carcinoma (EPC). The patient was lost to follow-up and did not obtain definitive treatment. Breast cancer rarely presents as a breast hematoma. However, as in this case, if the hematoma fails to resolve, further investigation is warranted. The prognosis of EPC is excellent when identified and treated appropriately.

Possibility to discriminate benign from malignant breast lesions detected on dual-layer spectral CT-evaluation

OBJECTIVES

Intramammary mass lesions are reportedly present in up to 5.8% of all contrast enhanced CT-examinations of the female chest. We aimed to assess whether their biological relevance can be estimated using spectral CT-datasets.

METHODS

In this bicentric retrospective study patients with breast masses visualized on spectral CT-examinations from 07/2017 to 06/2019 were included. Lesions were characterized as malignant or benign based on histology and/or a stable follow-up of >2 years. Conventional CT-images, iodine density-maps, virtual monoenergetic-images (40 keV, 100 keV) and Zeffective-maps were evaluated by two independent readers. Statistical analysis derived from the Regions of interest (ROIs) was done by calculating the Areas under the Receiver operating characteristic (ROC) curve (AUC) and Youden-indices.

RESULTS

106 breast masses (malignant/benign: 81/25, 76.4%/23.6%) were included. The mean AUCs of the variables "iodine content" (reader 1/2:0.97;0.98), "monoenergetic curve-slope" (0.97;0.96) and "Zeffective" (0.98;0.98) measured in the target lesions (TL) showed superior results compared to those derived from the variable "density" (0.92;0.93) (p < 0.001). The ratios "TL to aorta" calculated for the variables "iodine content", "monoenergetic curve-slope" and "Zeffective" showed superior results compared to normal breast tissue and muscle (p < 0.001). The optimal cutpoint for the "iodine content" in the TL was 0.7-0.9 mg/ml (sensitivity 96.6%, specificity 91.7%). The best diagnostic results were achieved by normalizing the iodine content in the TL to that in the aorta (optimal cutpoint 0.1, sensitivity 95.5%, 98.9%, specificity 91.7%).

CONCLUSIONS

Our preliminary results suggest that spectral CT-datasets might allow to estimate the biological dignity of breast masses detected on clinically indicated chest-examinations.

Suspicious breast lesions incidentally detected on chest computer tomography with histopathological correlation

OBJECTIVE

To evaluate incidental breast lesions on chest computed tomography with histopathological correlation. It is important for general radiologist to characterize a breast lesion as benign, indetermined, or sufficiently suspicious to warrant further work-up.

METHODS

A total of 35.000 chest CT examinations were performed between January 2016 and December 2020. 27 patients (mean age 70 years, age range 48-87 years) with incidental breast lesions were identified in this retrospective study. Two radiologists scored incidental breast lesions independently regarding their morphology, and the results were compared to histopathology which was obtained by an ultrasound-guided core needle biopsy or a surgical excision.

RESULTS

Out of 35.000 chest CT examinations, a total of 31 incidental breast lesions in 27 patients were detected. Among the 31 lesions, 23 were malignant and 8 benign. The malignant lesions included 17 carcinomas and 6 metastases (4 lymphomas and 2 melanomas). The benign lesions contained 2 hematomas, 4 fat necrosis, and 2 fibrosis lumps.

CONCLUSION

Chest computed tomography as a standard imaging technique is helpful for evaluation of suspicious breast lesions. This may ultimately influence patient management and lead to further imaging.

Incidental Breast Findings on Computed Tomography and MR Imaging

Computed tomography (CT) and magnetic resonance (MR) imaging may demonstrate a wide variety of incidental findings in the breast, including primary breast carcinoma, the second most common cancer in women. It important to recognize the spectrum of pathologic conditions in order to properly assess the need for further workup. Some findings may be diagnosed as benign on the basis of CT/ MR imaging and clinical history alone, whereas others will require evaluation with dedicated breast imaging and possibly biopsy. This article serves to guide radiologists' management of the wide spectrum of incidental breast findings encountered on cross-sectional imaging.

Breast Metastases: Updates on Epidemiology and Radiologic Findings

Purpose The aim of this study was to report the prevalence of secondary breast malignancies and analyze their radiological characteristics. Materials and methods We collected 42,505 pathological reports of mammary biopsies performed from January 2000 to January 2019 in our hospital database, from which we screened reports of secondary cancer of the breast. We collected and analyzed imaging data from computed tomography (CT), ultrasound (US), and mammography. Mammograms, CT scans, and US images were reviewed by two breast radiologists. Prevalence of secondary breast malignancy among suspicious breast masses and all breast malignancies were calculated. Results Out of 42,505 histopathology reports from mammary biopsies, we found 19,354 malignancies. We identified 33 cases of secondary breast cancers (0.08% of suspicious breast lesions, 0.17% of breast malignancies). Most common metastases were from lymphoma (23 cases, 0.05% of suspicious breast lesions, 0.12% of breast malignancies) and melanoma (six cases, 0.01% of suspicious breast lesions, 0.03% of breast malignancies). All secondary lesions were hypoechoic on US and showed high density on mammogram. On CT, 83% of the lesions appeared solid/dense, and 17% were mixed, alternating areas of iso/hyperdensity with areas of hypodensity. Conclusion Secondary breast cancer had a prevalence of 0.17% among all breast malignancies. No specific imaging features, characteristic of secondary breast cancer, were found.

Latissimus Dorsi flap enhancement by lipofilling as an immediate breast reconstruction technique for skin-preserving mastectomy

AIM

To evaluate Latissimus Dorsi flap (LD) enhancement by lipofilling as an immediate breast reconstruction technique, for skin-preserving mastectomy regarding oncological safety, fat graft resorption after radiotherapy, and patients' satisfaction.

PATIENTS AND METHODS

This is a prospective study that included female patients complaining of breast cancer. Patients were subjected to skin-preserving mastectomy associated with Latissimus Dorsi flap enhancement by lipofilling using the multisite, and multilayer fat grafting technique of injection. Patients were followed up for early and late postoperative complications including recurrence. Volumetric CT was performed before and after the radiotherapy to detect the percentage of fat resorption. Postoperative patients' satisfaction was assessed using the Kyungpook National University Hospital (KNUH) Breast Reconstruction Satisfaction Questionnaire.

RESULTS

The study included 25 female patients with a mean age of 36.48 ± 5.87 years. The mean period of follow-up was 30.32 ± 5.82 months. Local recurrence was encountered in 1 patient (4%). The mean volume reduction of the injected fat graft was 27.36 ± 8.58%. Twenty-three patients (92%) declared their satisfaction after the operation, one of them was satisfied only after she underwent a second session of lipofilling.

CONCLUSIONS

Skin-preserving mastectomy with the enhancement of the LD by lipofilling for immediate reconstruction of the breast seems to be a safe and simple technique for the achievement of autologous breast reconstruction. It has an acceptance rate of locoregional recurrence and minor postoperative complications. The procedure showed high postoperative patients' satisfaction and a reasonable percentage of fat resorption as confirmed by volumetric CT imaging techniques.

A Case of Asymmetric Nipple Enhancement as an Imaging Precursor to Invasive Ductal Carcinoma

On multidetector computed tomography (CT), it is important to scrutinize the imaged portions of the breasts. In recent years, the dramatic rise in CT imaging has led to the increased detection of incidental breast lesions. We describe a case of invasive ductal carcinoma that presented as stage IV cancer, and retrospective review of prior imaging study revealed asymmetric nipple enhancement on a trauma protocol CT chest acquired three years earlier. This report highlights the importance of being attentive to breast abnormalities on CT performed for indications other than breast disease and additionally focuses on the approach to address abnormal enhancement of the nipple areolar complex (NAC).

Hematoma Mimicking Breast Cancer on CT Scan and Breast Ultrasound

There are many benign breast lesions that mimic breast cancer on breast imaging. Postlumpectomy scar, hematoma, fat necrosis, diabetic mastopathy, and granulomatous mastitis are examples of benign breast lesions that have suspicious breast imaging findings. Mammogram and breast ultrasound are the imaging studies to evaluate breast findings. CT scan is not used to evaluate breast findings because it delivers high radiation dose to the breast, and breast tissue is often confused as breast masses on CT scan. The following case demonstrates an incidentally detected breast mass on CT scan performed to assess for pulmonary embolism. The CT scan and subsequent breast ultrasound both demonstrated suspicious breast imaging findings. Final pathology from ultrasound-guided biopsy revealed hematoma. This benign finding was concordant with the patient’s medical history of cirrhosis with low platelet count and medication history of warfarin.

Breast mass assessment on chest CT: Axial, sagittal, coronal or maximal intensity projection?

OBJECTIVES

The goal of this work is to determine the optimal projection to detect breast masses on Chest CT.

METHODS

Institutional Review Board (HIPPA compliant) approval was obtained with a waiver of consent. 10 image pairs of Chest CT images containing breast masses were selected for review by 10 chest radiologists: the pairs consisted of axial, sagittal, coronal and axial MIP images (MIP images) with each projection compared to a MIP and with one another. For each pair, the image where the mass was most conspicuous was recorded.

RESULTS

MIPs were preferred to any cross sectional projection 82% of the time; sagittal (63%) or coronal (63%) images were preferred to the axial projection. When sagittal and coronal images were compared there was no preference.

CONCLUSIONS

MIP images should be obtained and reviewed for breast pathology; sagittal or coronal projections may provide additional information.

Value of tomography in detecting breast masses and discriminating malign and benign lesions

Objectives

The main purpose of the present study was to determine the effectivity of computerized tomography (CT) in detecting breast masses and discriminating masses as malignant or benign.

Material and Methods

After having received the institutional local ethics committee approval, an experienced radiologist who did not participate in the study created a patient pool by searching our health center's Pathology department database between 2010 and 2018. The group created consisted of dense and non-dense breast types equally and included approximately similar percentages of benign and malignant breast mass sizes. Finally, 70 subjects were included: 30 females with definite malign, 20 with definite benign breast masses, and 20 without any breast pathology based on mammography and ultrasonography results, who were considered as the control group. Three experienced Radiologists (R1, R2, R3) who were not aware of the final diagnosis evaluated all images independently. Radiologist performance was assessed by calculating the area under the receiver operating characteristic curve (AUC) and interobserver reliability values were estimated by intraclass correlation coefficient (ICC) analysis.

Results

The diagnostic accuracy suitability of CT according to BI-RADS scores for R1, R2 and R3 were found as p <0.001, p <0.001 and p <0.001, respectively. There were significant interobserver reliability rates between all investigators (p= 0.0001).

Conclusion

CT may be used as a valuable diagnostic tool in discriminating breast masses with further training in widely varying appearances of normal breast tissues leading to false positive findings.

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.

A practical guide to managing CT findings in the breast

While it is well accepted that CT is not an optimal imaging study to evaluate the breasts, findings on chest CT may be the first indication of an occult malignancy. The nonspecific appearance of breast findings and the lack of consensus guidelines for managing incidental breast findings may dissuade radiologists from thoroughly evaluating the breasts on CT. We review commonly encountered breast findings on CT and present an algorithm for managing incidentally detected breast findings.

Abdominal-pelvic scanning parameters revisited: a case for Z-axis reduction in patients with clinical suspicion for acute appendicitis

PURPOSE

The purpose of this study was to determine if CT for appendicitis can be abbreviated to begin at the top of the L2 vertebral body level and still maintain the detection rate of appendicitis and other symptomatic pathology without omitting significant incidental findings.

METHODS

Retrospective review of CT abdomen-pelvis exams for suspected appendicitis over a 5-month period was performed. The Z-axis scan length of the original full scans and theoretical limited scans from the top of L2 were recorded and calculated. Images were reviewed for incidental findings above the L2 vertebral body level and categorized by severity per American College of Radiology (ACR) white paper guidelines. Final diagnoses based on imaging findings were also recorded.

RESULTS

One hundred nineteen patients (46 males, 73 females, mean age 29 ± 14) were included. Appendicitis was present in 26 cases (22%). Using a theoretical scan beginning at the top of the L2 vertebral body, none of the findings leading to diagnosis of appendicitis would have been missed. A total of 30 incidental findings were found above the L2 vertebral body. Per ACR white paper guidelines, 26 of these findings did not require additional imaging follow-up. Additional follow-up imaging was recommended for 3 of the findings above L2, and 1 right adrenal metastasis was found above L2 in a patient with previously undiagnosed NSCLC. This patient coincidentally also had appendicitis. No symptomatic pathology would have been missed had the scans begun at the top of the L2 vertebral body. Such an abbreviated scan would have resulted in a mean Z-axis reduction of 12.9 cm (30.3%).

CONCLUSIONS

CT using abbreviated Z-axis scan length can reduce radiation dose and provide necessary imaging needed to diagnose appendicitis or other symptomatic pathology without omitting significant incidental findings.

Semi-automated enhanced breast tumor segmentation for CT image

Accurate detection of breast cancer region is essential for treatment. X-ray computed tomography (CT) is an effective diagnostic method of breast cancer besides MRI and ultrasound. In this paper, a semi-automated breast cancer segmentation method was proposed to CT images. First, maximum region searching was used to find the rough boundary of the lesion. Then, a modified Histogram Equalization with Iterative-Filling was adopted to enhance the lesion and avoid the unbalanced intensity in the target region. Finally, a four-seeds Random Walk was used for accurate segmentation. The method was validated on a clinical dataset with 50 cases containing 630 slices in total. The experiments showed that the Dice Coefficient of our method was 88.6%, which was higher than that of Random Walk (76.9%) and Graph-Cut (79.8%).

Incidentally detected breast lesions on chest CT with US correlation: a pictorial essay

With the increasing use of computed tomography (CT), incidental breast lesions are detected more frequently. When interpreting chest CT findings, it is important for radiologists to carefully review the breast to recognize any abnormal findings that could affect patient management. The purpose of this study is to discuss incidental breast lesions on chest CT with ultrasonography correlation that may be encountered in routine clinical practice.

Breast Fibroadenoma With Increased Activity on 68Ga DOTATATE PET/CT

Fibroadenoma is the most common benign breast tumor in women of reproductive age, carrying little to no risk of breast cancer development. We report on a case of a woman with history of neuroendocrine tumor who on follow-up imaging tests underwent whole-body PET/CT study using Ga DOTATATE. The scan showed increased focal activity in the right breast, which was biopsied revealing a fibroadenoma. The presented data suggests cell surface overexpression of somatostatin receptors by this benign breast tumor. Moreover, this finding emphasizes the need for cautious interpretation of Ga DOTATATE-avid breast lesions that could mimic malignancy in neuroendocrine tumor patients.

Spectrum of the Breast Lesions With Increased 18F-FDG Uptake on PET/CT

Interpretation of ¹⁸F-FDG PET/CT studies in breast is challenging owing to nonspecific FDG uptake in various benign and malignant conditions. Benign conditions include breast changes in pregnancy and lactation, gynecomastia, mastitis, fat necrosis, fibroadenoma, intraductal papilloma, and atypical ductal hyperplasia. Among malignancies, invasive ductal carcinoma and invasive lobular carcinoma are common histological types of breast carcinoma. Rarely, other unusual histological types of breast carcinomas (eg, intraductal papillary carcinoma, invasive micropapillary carcinoma, medullary carcinoma, mucinous carcinoma, and metaplastic carcinoma), lymphoma, and metastasis can be the causes. Knowledge of a wide spectrum of hypermetabolic breast lesions on FDG PET/CT is essential in accurate reading of FDG PET/CT. The purpose of this atlas article is to demonstrate features of various breast lesions encountered at our institution, both benign and malignant, which can result in hypermetabolism on FDG PET/CT imaging.

Characterization of a murine xenograft model for contrast agent development in breast lesion malignancy assessment

Background

The aim of the study was to develop a nude mouse xenograft model implanted with both benign and malignant xenografts as the preliminary candidate screening tool for contrast agent development in lesion malignancy indication.

Results

A malignant xenograft (either MCF-7 cell/matrigel™ or MDA-MB 231 cell/matrigel) and a benign xenograft (culture medium/matrigel) with cleft and slit-like features of intracanaliculer fibroadenoma were implanted subcutaneously into flanks of individual nu/nu nude mouse with >90 % successful inoculation rate. Both malignant and benign xenografts with volume up to 4 cm³ and (size up to 2 cm) after 5^th week were characterized in vivo by sonogram (exhibiting endogenous morphological contrast features between benign and malignant xenografts), dynamic contrast enhanced multi-detector computed tomography (presenting non-targeting exogenous morphological and dynamic contrast features between benign and malignant xenografts), and then were harvested for histological and immunohistochemistry (revealing example of targeting/molecular contrast features, such as expression of cancer vascular markers of malignant xenografts). Malignant xenografts appeared morphologically taller than wide (axis parallel to skin) with angular/ill-defined margin under sonogram observations, revealed more evident rim enhancement, angular margin and washout pattern in the time-density curve from dynamic contrast enhance multi-detector computed tomography images, and had more visible cancer vascular markers (CD31 and VEGF) expression. With limited number of subjects (5–27 for each group of a specific imaging contrast feature), those imaging contrast features of the xenograft model had larger than 85 % sensitivity, specificity, accuracy, positive and negative prediction values in indicating xenograft malignancy except for results from color Doppler detections.

Conclusions

The murine xenograft model might provide an earlier efficacy evaluation of new contrast agent candidate for lesion malignancy interrogation with qualitative and quantitative indication before a human study to reduce the risk and conserve the resources (time, finance and manpower).

Differentiation of Malignant and Benign Incidental Breast Lesions Detected by Chest Multidetector-Row Computed Tomography: Added Value of Quantitative Enhancement Analysis

To retrospectively determine the association between breast lesion morphology and malignancy and to determine the optimal value of lesion enhancement (HU, Hounsfield units) to improve the diagnostic accuracy of breast cancer in patients with incidental breast lesions (IBLs). A total of 97 patients with 102 IBLs detected from July 2009 to December 2012 were enrolled in this study. Two radiologists analyzed CT images for the presence of malignancy based on the morphology of the lesions alone and in combination with an enhancement value (HU) analysis. There were 36 malignant and 66 benign IBLs. When the morphology and enhancement values were combined, the sensitivity, specificity, and accuracy were 92%, 97%, and 95%, respectively, for reader 1 and 89%, 94%, and 92%, respectively, for reader 2. The addition of HU values led to correct changes in the diagnosis; specifically, the accuracy of the diagnosis of reader 1 and reader 2 improved by 6.9% and 11.8%, respectively. The addition of the enhancement value (HU) to the CT morphology improved the diagnostic accuracy in the differentiation of malignant from benign IBLs by using the region of interest (ROI) to measure the HU within the most suspicious part of the lesion.

Incidental Breast Lesions Detected on Computed Thorax Tomography

OBJECTIVE

Although mammography is the primary imaging method of the breast, incidental benign and malignant breast lesions are increasingly being detected on computed tomographies (CTs) performed to detect different pathologies. Therefore, the detection and accurate identification of these lesions is important. In this study, we aimed to evaluate the frequency, morphological features, and results of incidental breast lesions on CTs performed for the detection of extramammarian pathologies.

MATERIALS AND METHODS

Incidental breast lesions on CTs performed in our department between 2011 and 2013 were evaluated. Patients who had previously diagnosed breast lesions were excluded from the study. The inclusion criteria were histopathologic diagnose and being followed-up for at least 2 years.

RESULTS

The study population consisted of 33 women whose mean age was 55±1.38 (37-78) years. Of the 33 women, 12 (36%) had malignant and 21 (64%) had benign or normal findings. The most common malignant lesion was invasive ductal carcinoma, and the most common benign lesion was fibroadenoma. Ill-defined contour and lymphadenopathy in malignant lesions and well-defined contour in benign lesions were the most important CT findings.

CONCLUSION

Breast must be carefully evaluated if it is included in the scans. An accurate report of breast lesions gives an opportunity for early diagnosis and treatment.

Targeted sonography using an image fusion technique for evaluation of incidentally detected breast lesions on chest CT: a pilot study

BACKGROUND

With increasing use of computed tomography (CT), incidentally detected breast lesions are being encountered more frequently. The aim of our study was to verify the utility of targeted sonography using an image fusion technique, real-time virtual sonography (RVS) that coordinates real-time sonography images with previously obtained CT images using a magnetic position tracking system, for evaluation of incidentally detected breast lesions on chest CT.

METHODS

Eleven lesions in 11 women with no history of breast cancer who were referred to our unit for assessment of breast lesions incidentally detected on CT were enrolled in this study. To assess the efficacy of targeted sonography using RVS, we analyzed the frequency of sonographic detection of incidentally detected breast lesions and the difference between sonography- and CT-determined diameters.

RESULTS

Using RVS guidance, all 11 lesions were sonographically detected. Ten (91 %) of 11 lesions underwent sonography-guided biopsy, yielding a success rate of 90 % (9/10). The remaining sonography-guided biopsy failure lesion required surgical biopsy for definitive diagnosis; this was performed after RVS was used to mark CT imaging information onto the breast surface. Four (36 %) lesions subsequently proved to be malignant. The mean diameters provided by RVS were 14.9 ± 6.7 mm for sonography and 16.8 ± 7.5 mm for CT (p = 0.538).

CONCLUSION

Using RVS, a sonographic probe was precisely guided to the lesions. Our results suggest that targeted sonography using RVS is a useful technique for identifying incidentally detected breast lesions on chest CT.

Benign breast lesions detected by positron emission tomography-computed tomography

(18)F-fluorodeoxyglucose positron emission computed tomography (FDG PET-CT) is widely used in the initial staging and response evaluation of patients with malignancy. This review describes a spectrum of benign breast findings incidentally detected by FDG PET-CT at staging that may be misinterpreted as malignancy. We describe the pattern of distribution and intensity of FDG uptake in a spectrum of benign breast diseases with their corresponding typical morphological imaging characteristics to help the nuclear medicine physician and/or general radiologist identify benign lesions, avoiding unnecessary breast imaging work-up and biopsies.

Nodular fasciitis in the axillary tail of the breast

Nodular fasciitis is a benign proliferation of myofibroblasts which presents clinically as a rapidly growing mass with nonspecific features on imaging and high cellular activity on histopathology. Nodular fasciitis can be mistaken for malignant fibrous lesions such as soft tissue sarcoma or breast carcinoma when located within breast tissue. This presents a problem for appropriate treatment planning as the natural history of nodular fasciitis is spontaneous regression. We present the mammographic, sonographic, computed tomography, and histopathologic characteristics of nodular fasciitis in a 68 year female initially presenting with a rapidly enlarging right axillary mass.

Comparison between incidental malignant and benign breast lesions detected by computed tomography: a systematic review

INTRODUCTION

With increasing use of CT for a variety of diagnostic pathways, breast incidentalomas will be identified more frequently. Therefore, it is important for radiologists to know typical CT appearances of malignant and benign breast lesions. The aim of this study was to compare radiological features of benign and malignant incidental breast findings on CT reported in the literature.

METHODS

A search for appropriate studies published between 1988 and 2012 yielded five results with a total of 214 patients/257 lesions. Morphological features of the described breast masses, such as shape, margins, enhancement, axillary lymphadenopathy and calcifications, were analysed.

RESULTS

The prevalence of incidental breast carcinoma varied from 9.2% to 60.9% of the lesions. The frequency of benign lesions was 30.4-71.8%. The remaining incidental findings were intramammary metastases and primary or secondary breast lymphomas. Malignant lesions were larger in size, were round in shape and demonstrated a higher density compared with benign lesions. There was no significant difference in the margin characteristics of the masses between the groups. The morphological features previously postulated as typical for malignancy turned out to be non-specific.

CONCLUSIONS

Benign and malign breast incidentalomas are not safely distinguished from each other on standard chest CT. Therefore, all breast incidentalomas should be evaluated by further radiological/histological investigations.

Technical parameters and interpretive issues in screening computed tomography scans for lung cancer

Lung cancer screening computed tomographies (CTs) differ from traditional chest CT scans in that they are performed at very low radiation doses, which allow the detection of small nodules but which have a much higher noise content than would be acceptable in a diagnostic chest CT. The technical parameters require a great deal of attention on the part of the user, because inappropriate settings could result in either excess radiation dose to the large population of screened individuals or in low-quality images with impaired nodule detectability. Both situations undermine the main goal of the screening program, which is to detect lung nodules using as low a radiation dose as can reasonably be achieved. Once an image has been obtained, there are unique interpretive issues that must be addressed mainly because of the very high noise content of the images and the high prevalence of incidental findings in the chest unrelated to the sought-after pulmonary nodules.

Incidentally detected enhancing breast lesions on chest computed tomography

Objective

To evaluate the nature and imaging appearance of incidental enhancing breast lesions detected on a routine contrast-enhanced chest CT.

Materials and Methods

Twenty-three patients with incidental enhancing breast lesions on contrast-enhanced chest CT were retrospectively reviewed. The breast lesions were reviewed by unenhanced and enhanced CT, and evaluated by observing the shapes, margins, enhancement patterns and backgrounds of breast lesions. A histopathologic diagnosis or long-term follow-up served as reference standard.

Results

Sixteen (70%) patients had malignant breast lesions and seven (30%) had benign lesions. In 10 patients, the breast lesions were exclusively detected on contrast-enhanced CT. Using unenhanced CT, breast lesions with fibroglandular backgrounds were prone to be obscured (p < 0.001). Incidental primary breast cancer showed an non-significant trend of a higher percentage irregular margin (p = 0.056). All of the four incidental breast lesions with non-mass-like enhancement were proven to be malignant.

Conclusion

Routine contrast-enhanced chest CT can reveal sufficient details to allow for the detection of unsuspected breast lesions, in which some cases may be proven as malignant. An irregular margin of incidental enhancing breast lesion can be considered a suggestive sign of malignancy.

The incidence and outcome of incidental breast lesions detected by computed tomography

INTRODUCTION

In the UK, the majority of breast cancers are diagnosed through symptomatic breast clinics and the breast screening programmes. With increased use of computed tomography (CT) to assess various pathologies, breast lesions are picked up incidentally. The aim of this study was to investigate the incidence and outcomes of breast lesions detected incidentally on CT scans.

PATIENTS AND METHODS

A retrospective study was conducted to assess the incidence and outcome of incidentally found breast lesions, which were detected on chest CT scans that were conducted for other pathologies during the period from February 2007 to October 2008.

RESULTS

A total of 432 chest CT scans were performed over 18 months. Thirty-three (7.63%) patients were found to have an incidental breast lesion. The mean age was 73 years (range, 50-86 years). Of these, 17 (52%) were benign, eight (24%) were primary breast cancer and the remaining eight (24%) had no definite pathology. The detection rate of breast cancer was 1.85%.

CONCLUSIONS

CT is emerging as an important contributor to the detection of occult breast lesions. Radiological awareness of incidental breast lesions is important so that appropriate referral to a specialised breast unit is made.

Incidental breast lesions detected on CT: what is their significance?

An increasing number of breast lesions are being detected incidentally on CT. The aim of this study was to investigate the rate of referrals to the breast unit for assessment of lesions identified on CT and the resulting yield of previously undiagnosed breast malignancies from this pathway. A retrospective review was undertaken of CT examinations conducted over a period of 14 years. All patients (with no previous history of breast cancer) whose report contained the keyword "breast" and who were referred to a specialist breast unit for assessment were reviewed. CT lesion morphology and enhancement pattern were identified and compared with the final diagnostic outcome. 70 patients were identified by retrospective analysis, yielding 78 incidental breast lesions, of which 22 (28.2%) were malignant (category B5). This gave a positive predictive value (PPV) for malignancy of 28.2%. The best morphological predictor of malignancy was spiculation (PPV, 76%) and irregularity (PPV, 58%), whereas calcification patterns (PPV, 36%) were diagnostically unhelpful. Malignant lesions were likely to be larger (mean, 28.5 mm) than benign lesions (mean, 20.2 mm; p<0.05). In conclusion, 30% of incidental breast lesions in this large series of patients proved to be unsuspected breast cancers, particularly irregular spiculated masses. Referral for formal triple assessment of CT-diagnosed breast lesions is worthwhile, and careful examination of the breast should be a routine part of CT examinations.