Computed diffusion-weighted imaging with a low-apparent diffusion coefficient-pixel cut-off technique for breast cancer detection.

OBJECTIVE: This study aimed to compare the image quality and diagnostic performance of computed diffusion-weighted imaging (DWI) with low-apparent diffusion coefficient (ADC)-pixel cut-off technique (cDWI cut-off) and actual measured DWI (mDWI). METHODS: Eighty-seven consecutive patients with malignant breast lesions and 72 with negative breast lesions who underwent breast MRI were retrospectively evaluated. Computed DWI with high b-values of 800, 1200, and 1500 s/mm2 and ADC cut-off thresholds of none, 0, 0.3, and 0.6 (×10-3 mm2/s) were generated from DWI with two b-values (0 and 800 s/mm2). To identify the optimal conditions, two radiologists evaluated the fat suppression and lesion reduction failure using a cut-off technique. The contrast between breast cancer and glandular tissue was evaluated using region of interest analysis. Three other board-certified radiologists independently assessed the optimised cDWI cut-off and mDWI data sets. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis. RESULTS: When an ADC cut-off threshold of 0.3 or 0.6 (× 10-3 mm2/s) was applied, fat suppression improved significantly (p < .05). The contrast of the cDWI cut-off with a b-value of 1200 or 1500 s/mm2 was better than the mDWI (p < .01). The ROC area under the curve for breast cancer detection was 0.837 for the mDWI and 0.909 for the cDWI cut-off (p < .01). CONCLUSION: The cDWI cut-off provided better diagnostic performance than mDWI for breast cancer detection. ADVANCES IN KNOWLEDGE: Using the low-ADC-pixel cut-off technique, computed DWI can improve diagnostic performance by increasing contrast and eliminating un-suppressed fat signals.

Automatic detection of punctate white matter lesions in infants using deep learning of composite images from two cases.

Punctate white matter lesions (PWMLs) in infants may be related to neurodevelopmental outcomes based on the location or number of lesions. This study aimed to assess the automatic detectability of PWMLs in infants on deep learning using composite images created from several cases. To create the initial composite images, magnetic resonance (MR) images of two infants with the most PWMLs were used; their PWMLs were extracted and pasted onto MR images of infants without abnormality, creating many composite PWML images. Deep learning models based on a convolutional neural network, You Only Look Once v3 (YOLOv3), were constructed using the training set of 600, 1200, 2400, and 3600 composite images. As a result, a threshold of detection probability of 20% and 30% for all deep learning model sets yielded a relatively high sensitivity for automatic PWML detection (0.908-0.957). Although relatively high false-positive detections occurred with the lower threshold of detection probability, primarily, in the partial volume of the cerebral cortex (≥ 85.8%), those can be easily distinguished from the white matter lesions. Relatively highly sensitive automatic detection of PWMLs was achieved by creating composite images from two cases using deep learning.

Quantitative Values from Synthetic MRI Correlate with Breast Cancer Subtypes.

The purpose of this study is to correlate quantitative T1, T2, and proton density (PD) values with breast cancer subtypes. Twenty-eight breast cancer patients underwent MRI of the breast including synthetic MRI. T1, T2, and PD values were correlated with Ki-67 and were compared between ER-positive and ER-negative cancers, and between Luminal A and Luminal B cancers. The effectiveness of T1, T2, and PD in differentiating the ER-negative from the ER-positive group and Luminal A from Luminal B cancers was evaluated using receiver operating characteristic analysis. Mean T2 relaxation of ER-negative cancers was significantly higher than that of ER-positive cancers (p < 0.05). The T1, T2, and PD values exhibited a strong positive correlation with Ki-67 (Pearson's r = 0.75, 0.69, and 0.60 respectively; p < 0.001). Among ER-positive cancers, T1, T2, and PD values of Luminal A cancers were significantly lower than those of Luminal B cancers (p < 0.05). The area under the curve (AUC) of T2 for discriminating ER-negative from ER-positive cancers was 0.87 (95% CI: 0.69−0.97). The AUC of T1 for discriminating Luminal A from Luminal B cancers was 0.83 (95% CI: 0.61−0.95). In conclusion, quantitative values derived from synthetic MRI show potential for subtyping of invasive breast cancers.

Breast Cancer Subtypes and Quantitative Magnetic Resonance Imaging: A Systemic Review.

Magnetic resonance imaging (MRI) is the most sensitive imaging modality for breast cancer detection. This systematic review investigated the role of quantitative MRI features in classifying molecular subtypes of breast cancer. We performed a literature search of articles published on the application of quantitative MRI features in invasive breast cancer molecular subtype classification in PubMed from 1 January 2002 to 30 September 2021. Of the 1275 studies identified, 106 studies with a total of 12,989 patients fulfilled the inclusion criteria. Bias was assessed based using the Quality Assessment of Diagnostic Studies. All studies were case-controlled and research-based. Most studies assessed quantitative MRI features using dynamic contrast-enhanced (DCE) kinetic features and apparent diffusion coefficient (ADC) values. We present a summary of the quantitative MRI features and their correlations with breast cancer subtypes. In DCE studies, conflicting results have been reported; therefore, we performed a meta-analysis. Significant differences in the time intensity curve patterns were observed between receptor statuses. In 10 studies, including a total of 1276 lesions, the pooled difference in proportions of type Ⅲ curves (wash-out) between oestrogen receptor-positive and -negative cancers was not significant (95% confidence interval (CI): [-0.10, 0.03]). In nine studies, including a total of 1070 lesions, the pooled difference in proportions of type 3 curves between human epidermal growth factor receptor 2-positive and -negative cancers was significant (95% CI: [0.01, 0.14]). In six studies including a total of 622 lesions, the pooled difference in proportions of type 3 curves between the high and low Ki-67 groups was significant (95% CI: [0.17, 0.44]). However, the type 3 curve itself is a nonspecific finding in breast cancer. Many studies have examined the relationship between mean ADC and breast cancer subtypes; however, the ADC values overlapped significantly between subtypes. The heterogeneity of ADC using kurtosis or difference, diffusion tensor imaging parameters, and relaxation time was reported recently with promising results; however, current evidence is limited, and further studies are required to explore these potential applications.

Two cases of oligometastatic castration-resistant prostate cancer detected by diffusion-weighted whole-body imaging with background body signal suppression.

INTRODUCTION: Treatment for oligometastasis in prostate cancer has changed from systemic therapy to metastatic lesion-targeted therapy. Early detection of metastatic lesions and assessment of the treatment response have become very important. Therefore, we started to perfume assessments with whole-body magnetic resonance imaging, especially diffusion-weighted imaging with background body signal suppression, as a modality to detect metastasis in patients with prostate cancer. CASE PRESENTATION: We encountered two cases of castration-resistant prostate cancer in which oligometastasis was detected by diffusion-weighted imaging with background body signal suppression. Metastasis-directed therapy was initiated for to treat the lesions in each case. The treatment was effective for disease control and symptom relief. Diffusion-weighted imaging with background body signal suppression could detect new lesions at an early phase and delineate changes in lesions immediately after therapy. CONCLUSION: Diffusion-weighted imaging with background body signal suppression enables early decision-making for metastasis-directed therapy compared with conventional imaging modalities. Further, metastasis-directed therapy targeting oligometastatic lesions detected by diffusion-weighted imaging with background body signal suppression may improve patients' overall survival and quality of life.

Cutaneous Metastases from Testicular Diffuse Large B-cell Malignant Lymphoma and Bowen Disease: 18F-FDG PET-CT Findings.

Here, we report the case of cutaneous metastases from testicular diffuse large B-cell malignant lymphoma (DLBCL) concurrent with Bowen disease evaluated with 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT). A 60-year-old male underwent orchiectomy to remove his left testicle because of DLBCL. Multiple skin lesions appeared 1 month postoperatively. Furthermore, an intractable erythematous plaque localized to the right lower leg was present from 2 years before the operation. 18F-FDG PET-CT images revealed multiple skin lesions with marked FDG uptakes in the face, neck, and thigh of this patient, as well as a lower leg lesion with minimal FDG uptake. Biopsy of both lesions revealed cutaneous metastases from DLBCL and Bowen disease (BD) of the lower leg lesion. 18F-FDG PET-CT images following chemotherapy and resection of BD demonstrated no FDG uptake.

Balanced Turbo Field Echo with Extended k-space Sampling: A Fast Technique for the Thoracic Ductography.

We evaluated the visibility of the thoracic duct by fast balanced turbo field echo with extended k-space sampling (bTFEe). The thoracic duct of 10 healthy volunteers was scanned by bTFEe using a 1.5-T magnetic resonance imaging (MRI), which was acquired in approximately 2 minutes. Three-dimensional (3D) turbo spin-echo (TSE) was obtained for comparison. The thoracic duct including draining location of the venous system was overall well visualized on bTFEe, compared to TSE.

Diagnostic performance of (18)F-fluorodeoxyglucose PET/CT and bone scintigraphy in breast cancer patients with suspected bone metastasis.

BACKGROUND: We prospectively compared the diagnostic accuracies of PET/CT and BS in patients with suspected bone metastases from breast cancer. METHODS: This single-institution prospective study included consecutive patients with suspected bone metastases from biopsy-proven breast cancer seen at Tokai University Hospital between September 2011 and March 2014. Inclusion criteria included suspicions for bone metastases (bone pain, elevated alkaline phosphatase, elevated tumor markers, or suspected bone metastases by BS). Two nuclear medicine physicians evaluated PET/CT and BS images. RESULTS: Thirty patients were initially enrolled in this study. Two were excluded from the analyses because they declined to undergo imaging during follow-up. PET/CT successfully detected bone metastases in all 10 patients finally diagnosed with the condition, whereas BS identified 2. The two methods were not highly concordant in detecting osseous metastases. In 19 of 28 paired studies (68 %), 2 (10 %) were positive for metastasis, and 17 (90 %) were negative. Nine occurrences (32 %) were discordant; of these, 2 were PET/CT positive and BS negative; 5 were PET/CT positive and BS equivocal; one was PET/CT negative and BS equivocal, and one was PET/CT equivocal and BS negative. CONCLUSIONS: Our results indicated that PET/CT was superior to BS for the diagnosis of bone metastases. On the basis of the results of previous studies as well as ours, PET/CT could replace BS as the initial modality to detect bone metastases in patients suspected for the condition.

A case of right renal artery originating from the thoracic aorta.

The renal arteries normally originate from the abdominal aorta between the first and second lumbar vertebrae. The main renal artery arising from the thoracic aorta is an uncommon anomaly. Here we report a rare case of a right renal artery originating above the celiac axis. A 38-year-old male underwent computed tomographic angiography in preparation for being a renal donor, and two right renal arteries were observed. A main renal artery arose from the thoracic aorta at the 11th thoracic vertebral level, and an accessory renal artery originated from the abdominal aorta at the renal hilum.

MRI-guided quadrantectomy in patients with ductal carcinoma in situ detected preoperatively by mammographic calcifications.

BACKGROUND: We designed MRI-guided quadrantectomy using 2-dimensional images reconstructed from MRI to enable virtual simulation of breast-conserving surgery. This study evaluated the efficacy of our approach, which involved projection of the 2-dimensional reconstruction images directly onto the breast to guide planned resection compared with the conventional approach with preoperative localization with hooked wires, for patients with ductal carcinoma in situ (DCIS) detected by mammographic calcifications. STUDY DESIGN: Eighty-six patients with calcifications ≥2 cm in diameter on mammogram who were diagnosed with DCIS on preoperative percutaneous biopsy underwent breast-conserving surgery. In 32 patients, lesion localization was done using the conventional technique of hooked wires. In 54 patients, preoperative planning was performed using supine MRI and projection of reconstructed 2-dimensional images directly onto the breast surface. Surgical outcomes in the 2 groups were compared. In the latter group, we also compared accuracy of DCIS detection between supine MRI and specimen mammography. RESULTS: Final pathologic assessment of the 86 patients was DCIS in 67 and DCIS with microinvasion (T1mic) in 19 patients. The rate of additional intraoperative margin resection and presence of DCIS at the surgical margin were significantly lower with our MRI-guided technique vs the hooked-wire approach. Supine MRI detected a considerably larger area of DCIS than did specimen mammography. CONCLUSIONS: Compared with a conventional approach using hooked wires, our MRI-guided quadrantectomy might be useful for patients with DCIS and DCIS with T1mic detected by mammographic calcifications, due to the superior ability to detect DCIS on MRI compared with mammography.

Diffusion-weighted imaging reflects pathological therapeutic response and relapse in breast cancer.

BACKGROUND: Conventional imaging does not always accurately depict the pathological response to neoadjuvant chemotherapy (NAC). Diffusion-weighted imaging (DWI) may provide additional insight into the chemotherapeutic effect. This study assessed whether the apparent diffusion coefficient (ADC) correlated with pathological outcome and prognosis in breast cancer patients receiving NAC. METHODS: Fifty-six patients with locally advanced breast cancer received surgery after NAC. Dynamic contrast-enhanced (DCE) and DWI were performed before and after NAC. The pathological response was classified into five categories from no response to complete response according to amount of residual cancer. The correlation between ADC and postoperative pathologic and prognostic outcome was assessed. RESULTS: The distribution of the pathological response classification was as follows: no response, 3 cases; mild response, 22 cases; moderate response, 12 cases; marked response, 11 cases; complete response, 8 cases. ADC after NAC correlated with pathological response, but ADC before NAC did not. The change in ADC after chemotherapy had better correlation coefficient (r = 0.67) than change in size (r = 0.58) and ADC after NAC (r = 0.64). Although the group with larger change of tumor size showed only marginal significance compared with the smaller change group (p = 0.089), the group with higher change of ADC showed significantly better prognosis than the lower one (p = 0.038). CONCLUSIONS: Change in ADC after chemotherapy better correlated with pathological outcome and prognosis than change in tumor size. DWI has potential in evaluating the pathological outcome of NAC in breast cancer patients.

Fat suppression strategies in MR imaging of breast cancer at 3.0 T: comparison of the two-point Dixon technique and the frequency selective inversion method.

PURPOSE: To compare two fat suppression methods in contrast-enhanced MR imaging of breast cancer at 3.0 T: the two-point Dixon method and the frequency selective inversion method. MATERIALS AND METHODS: Forty female patients with breast cancer underwent contrast-enhanced three-dimensional T1-weighted MR imaging at 3.0 T. Both the two-point Dixon method and the frequency selective inversion method were applied. Quantitative analyses of the residual fat signal-to-noise ratio and the contrast noise ratio (CNR) of lesion-to-breast parenchyma, lesion-to-fat, and parenchyma-to-fat were performed. Qualitative analyses of the uniformity of fat suppression, image contrast, and the visibility of breast lesions and axillary metastatic adenopathy were performed. RESULTS: The signal-to-noise ratio was significantly lower in the two-point Dixon method (P < 0.001). All CNR values were significantly higher in the two-point Dixon method (P < 0.001 and P = 0.001, respectively). According to qualitative analysis, both the uniformity of fat suppression and image contrast with the two-point Dixon method were significantly higher (P < 0.001 and P = 0.002, respectively). Visibility of breast lesions and metastatic adenopathy was significantly better in the two-point Dixon method (P < 0.001 and P = 0.03, respectively). CONCLUSION: The two-point Dixon method suppressed the fat signal more potently and improved contrast and visibility of the breast lesions and axillary adenopathy.

Detection of adrenal veins on selective retrograde CT adrenal venography in comparison with digital subtraction angiography in subjects with established diagnosis of one-sided adrenal aldosterone-producing tumor confirmed by adrenal vein sampling, histopathology and clinical course.

PURPOSE: Adrenal vein (AV) sampling (AVS) is the diagnostic gold standard for primary aldosteronism (PA), but right-sided AVS is difficult. We compared detection of AVs by selective retrograde CT adrenal venography (SRCTAV) with digital subtraction angiography (DSA). MATERIALS AND METHODS: Data on 29 subjects (11 males, mean age 55 y) with increased serum aldosterone concentrations (SAC) and a diagnosed right or left aldosterone-producing tumor (APT) by AVS who underwent laparoscopic adrenalectomy were retrospectively analyzed. Before AVS, visualizing AVs was attempted by DSA and SRCTAV (Aquilion). If after the adrenocorticotropic hormone loading test serum cortisol concentration (SCC) from either AV was >200 µg/dl, AVS was considered successful. If the SAC/SCC ratio for one side was ≥4 times higher than the other side, we diagnosed a one-sided APT. RESULTS: Left and right AV, respectively, were visualized in 29 (100%) and 22 subjects (76%) by DSA and 29 (100%) and 28 subjects (97%) by SRCTAV, with right-AV detection significantly higher by SRCTAV (p<0.05). Cannulations were regarded successful in 28 subjects having both AVs observed on SRCTAV but not in the remaining subject whose adrenocortical scintigram was positive, however. Adrenalectomy was performed with a diagnosis of adenoma. Among 28 subjects with successful AVS, histopathological diagnoses included adenoma (25), nodular hyperplasia (2) and normal (1). After adrenalectomy, antihypertensive drug usage in 28 patients was reduced or stopped with decreases in SAC (97%). CONCLUSIONS: Detection of AV was significantly higher by SRCTAV than DSA, especially on the right side, in 29 subjects diagnosed with one-sided APT.

Comparison of lymphoscintigraphy and indocyanine green lymphography for the diagnosis of extremity lymphoedema.

BACKGROUND: Lymphoscintigraphy is the gold-standard examination for extremity lymphoedema. Indocyanine green lymphography may be useful for diagnosis as well. We compared the utility of these two examination methods for patients with suspected extremity lymphoedema and for those in whom surgical treatment of lymphoedema was under consideration. METHODS: A total of 169 extremities with lymphoedema secondary to lymph node dissection and 65 extremities with idiopathic oedema (suspected primary lymphoedema) were evaluated; the utility of indocyanine green lymphography for diagnosis was compared with lymphoscintigraphy. Regression analysis between lymphoscintigraphy type and indocyanine green lymphography stage was conducted in the secondary lymphoedema group. RESULTS: In secondary oedema, the sensitivity of indocyanine green lymphography, compared with lymphoscintigraphy, was 0.972, the specificity was 0.548 and the accuracy was 0.816. When patients with lymphoscintigraphy type I and indocyanine green lymphography stage I were regarded as negative, the sensitivity of the indocyanine green lymphography was 0.978, the specificity was 0.925 and the accuracy was 0.953. There was a significant positive correlation between the lymphoscintigraphy type and the indocyanine green lymphography stage. In idiopathic oedema, the sensitivity of indocyanine green lymphography was 0.974, the specificity was 0.778 and the accuracy was 0.892. CONCLUSION: In secondary lymphoedema, earlier and less severe dysfunction could be detected by indocyanine green lymphography. Indocyanine green lymphography is recommended to determine patients' suitability for lymphaticovenular anastomosis, because the diagnostic ability of the test and its evaluation capability for disease severity is similar to lymphoscintigraphy but with less invasiveness and a lower cost. To detect primary lymphoedema, indocyanine green lymphography should be used first as a screening examination; when the results are positive, lymphoscintigraphy is useful to obtain further information.

Diffusion-weighted MRI as an adjunct to mammography in women under 50 years of age: an initial study.

PURPOSE: To evaluate diffusion-weighted magnetic resonance (DW) imaging as an adjunct to mammography for the detection of small invasive breast cancer. MATERIALS AND METHODS: Institutional review board standards were followed for this retrospective study. We performed both breast DW imaging and mammography on 25 women under 50 years of age with pathologically proven T1 breast cancer and on 21 healthy women under 50 years of age. Four offsite radiologists blind to the clinical information independently interpreted the mammograms and DW images and then classified their confidence level regarding the presence of breast cancer. The composite area under receiver operating characteristic curve (AUC), of mammography alone, DW imaging alone, and the combination of DW imaging and mammography (DWI/Cal) were calculated. RESULTS: The AUC of composite ROC curves of mammography, DW imaging, DWI/Cal combination, was 0.79 (95% CI, 0.72-0.87), 0.86 (95% CI, 0.84-0.87), and 0.96 (95% CI, 0.92-1.00), respectively. CONCLUSION: DW imaging may be a useful adjunct to mammography in the detection of small invasive breast cancer in women under 50 years of age.

Apparent diffusion coefficient correlation with oesophageal tumour stroma and angiogenesis.

OBJECTIVE: Because diffusion-weighted imaging (DWI) can predict the prognosis of patients with oesophageal squamous cell carcinoma (ESCC), we hypothesised that apparent diffusion coefficient (ADC) values might be correlated with the collagen content and tumour angiogenesis. The purpose of this study was to determine the correlation between ADC values of ESCC before treatment and oesophageal tumour stroma and angiogenesis. METHODS: Seventeen patients with ESCC were enrolled. The ADC values were calculated from the DWI score. Seventeen patients who had undergone oesophagectomy were analysed for tumour stroma, vascular endothelial growth factor (VEGF) and CD34. Tissue collagen was stained with azocarmine and aniline blue to quantitatively analyse the extracellular matrix in cancer stroma. Tissues were stained with VEGF and CD34 to analyse the angiogenesis. RESULTS: The ADC values decreased with stromal collagen growth. We found a negative correlation between the tumour ADC and the amount of stromal collagen (r = -0.729, P = 0.001), i.e. the ADC values decreased with growth of VEGF. We also found a negative correlation between the ADC of the tumours and the amount of VEGF (r = 0.538, P = 0.026). CONCLUSION: Our results indicated that the ADC value may be a novel prognostic factor and contribute to the treatment of oesophageal cancer. KEY POINTS: • Magnetic resonance apparent diffusion coefficient values inversely indicate tumour stromal collagen • There is also negative correlation between ADCs and vascular endothelial growth factor • ADC values may contribute to the treatment of oesophageal cancer.

Apparent diffusion coefficient values measured by diffusion-weighted imaging predict chemoradiotherapeutic effect for advanced esophageal cancer.

BACKGROUND: The purpose of this study was to assess whether apparent diffusion coefficient (ADC) values of esophageal squamous cell carcinoma (ESCC) predict responses to chemoradiotherapy (CRT) and/or patient prognosis. METHODS: Magnetic resonance images were acquired to construct the diffusion-weighted images, and the ADC values were calculated before CRT in 80 patients with ESCC. A high-ADC group responded better to CRT than did a low-ADC group (p < 0.01). We divided the 80 patients into two groups based on the operating characteristic analysis: one group comprised patients with ADC values higher than the average ADC of the esophageal cancer tissue (1.10 × 10(-3) mm2/s), and the other group comprised those whose ADC values were less than the average value. A Kaplan-Meier analysis showed that the survival rate in the high-ADC group was significantly better than that in the low-ADC group (p = 0.04). CONCLUSION: Our results indicate that the ADC value may be a useful marker to predict treatment response as well as survival for patients with ESCC.