Hiroshi Nakahara

A Comparison of MR Imaging, Galactography and Ultrasonography in Patients with Nipple Discharge

BackgroundThe aim of this study is to assess the usefulness of three-dimensional contrastenhanced magnetic resonance (MR) imaging, compared with galactography and ultrasonography (US).MethodsFifty-five patients with bloody nipple discharge were investigated retrospectively. All patients were examined by galactography, ultrasonography and MR imaging. These three sets of findings were compared with the histopathological results from 16 intraductal biopsies, 3 excisional biopsies, 24 microdochectomies and 12 mastectomies.ResultsContrast enhanced MR imaging demonstrated all malignant lesions including ductal carcinomain situ (DCIS). Four cases of DCIS were not visualized by ultrasonography and three malignant lesions were missed by galactography. In the MR study, segmental clumped enhancement (positive predictive value = 100%), and focal mass with smooth border (negative predictive value = 87.5%) were the statistically significant predictive factors.ConclusionsAmong the three modalities, contrast-enhanced three-dimensional MR imaging demonstrated the location and distribution of the lesions most clearly, especially in cases of ductal carcinomain situ. It has the potential to be a useful diagnostic tool for patients with nipple discharge.

MR and US imaging for breast cancer patients who underwent conservation surgery after neoadjuvant chemotherapy: comparison of triple negative breast cancer and other intrinsic subtypes

BackgroundNeoadjuvant chemotherapy (NAC) is commonly utilized to treat operable breast cancer. The purpose of this study was to review the findings of ultrasonography (US) and magnetic resonance (MR) imaging in patients treated with breast conservation surgery (BCS) after NAC with a focus on intrinsic subtypes.MethodsEighty-six patients underwent BCS after NAC. The tumors were classified into four subgroups by receptor status. US and MR were performed before and after NAC. The tumor diameters in US and MR after NAC were examined for correlations with pathological tumor distances in the specimens from BCS after NAC.ResultsThe correlation coefficient (r) of US to pathological tumor size was 0.3 in all tumors, 0.6 in HER2-type tumors, and 0.7 in triple negative breast cancers (TNBC). The correlation coefficient of tumor size in MR to pathological tumor size was 0.9 in TNBC, and other correlations were not statistically significant.ConclusionsThe correlation between tumor size in MR and pathological tumor size in triple negative breast cancers corresponded best. This information is one of the clues to selecting patients for BCS after NAC.

123I-MIBG myocardial scintigraphy in diabetic patients: Relationship with201Tl uptake and cardiac autonomic function

PurposeTo investigate the influence of diabetic myocardial damage (suspected myocardial damage; SMD) diagnosed by201T1-SPECT and diabetic cardiac autonomic neuropathy (AN) on myocardial MIBG uptake in patients with non-insulin-dependent diabetes mellitus (NIDDM).Subjects and MethodsEighty-seven diabetic patients divided into four subgroups: 23 with SMD (+) AN (+); 19 with SMD (+) AN (−); 27 with SMD (−) AN (+); 18 with SMD (−) AN (−), and 10 controls were studied. Both planar and SPECT images were taken at 30 minutes (early) and 3 hours (delayed) after123I-MIBG injection. The heart to mediastinum uptake ratio (H/M) and washout ratio of123I-MIBG (WR) were obtained from both planar images. On SPECT images, the total uptake score (TUS) was obtained by the 5 point score method by dividing the myocardium into 20 segments on visual analysis. Similarly, the difference between the201Tl image and the123I-MIBG image in TUS was taken as the difference in the total uptake score (ΔTUS) representing cardiac sympathetic denervation without SMD.ResultsOn both early and delayed planar images, the mean H/M value in the subgroups of diabetic patients was significantly lower in the SMD (+) AN (+) group than in the control group, but among those subgroups, there was statistically significant difference between the SMD (+) AN (+) and SMD (−) AN (−) groups only on the delayed images. Regarding the WR value, there was no statistically significant difference among subjects. On SPECT image analysis, the diabetic sub-group with AN or SMD had statistically significant lower values for TUS than those of the control group. Among diabetics, there was a statistically significant differences between SMD [+] AN [+] and SMD [−] AN [−] on both early and delayed images. Similarly, the SMD [+] AN [−] group also had significantly lower values than those of SMD [−] AN [−] on early images. Regarding ΔTUS, there was a statistically significant differences between AN [+] subgroups and controls. Similarly, the mean value for ΔTUS was much higher in AN [+] subgroups than in AN [−] subgroups with or without SMD in diabetes mellitus.Conclusion123I-MIBG myocardial uptake is affected by both SMD and cardiac autonomie neuropathy. Based on the finding that ΔTUS was much higher in AN [+] subgroups and there was no statistically significant difference between SMD [+] AN [+] and SMD [−] AN [+] subgroups, a decrease in myocardial123I-MIBG uptake might progress independently of SMD.

Three-Dimensional MR Imaging of Mammographically Detected Suspicious Microcalcifications

BackgroundThe purpose of this study was to evaluate the diagnostic value and clinical significance of three-dimensional MR imaging of the breast in patients with mammographically detected suspicious microcalcifications.MethodsForty patients with suspicious microcalcifications on mammography were evaluated with three-dimensional MR imaging. MR findings were grouped mainly by distribution of abnormal enhancement (linear, focal-clumped, segmental-clumped, segmental-stippled and diffuse-stippled). These findings were compared with the mammography findings according to the criteria of the Breast Imaging Reporting and Data System (BI-RADS) and histopathologic data.ResultsTwenty patients had proven malignancies, most frequently ductal carcinomain situ. For all the cases, linear (100%) and segmental-clumped type (100%) enhancement on MR imaging showed a significantly higher risk for malignancy. Diffuse stippled type (7%) and no enhancement (0%) on MR imaging indicated the lowest possibility of malignancy. 3D-MR imaging showed a sensitivity of 90%, a specificity of 95% and an overall accuracy of 93% in this study.ConclusionsThree-dimensional MR imaging of the breast can more accurately diagnose ductal carcinomain situ. Combined with mammography, this procedure is useful for reducing the number of false-positive biopsies and helpful for deciding the better management of patients with mammographically detected suspicious microcalcifications.

Clinicopathological study of invasive ductal carcinoma with large central acellular zone: special reference to magnetic resonance imaging findings.

Invasive ductal carcinoma (IDC) with central acellular zone is sometimes encountered, but its clinicopathological features have not yet been fully investigated. The clinicopathological features of 10 resected cases of IDC with a large central acellular zone were investigated. The tumor size ranged from 6 to 28 mm with a mean of 14.3 ± 6.9 mm. Contrast‐enhanced magnetic resonance imaging (MRI) showed a ring‐like appearance in the tumor. Sagittal fat‐suppressed T2‐weighted MRI had very high to intermediate signal intensity in a central area. Histologically, cancer tissue was located in the periphery of the tumor with a ring‐like pattern and a large central area was occupied by acellular amorphous tissue that was strongly stained by alcian blue. Lymph vessel permeation was seen in eight cases. Among the tumors with focal enhancement in the central areas >1 cm in diameter on contrast MRI, marked increase of microvessel was observed in the enhanced spot. The mean of p53 and Ki‐67 labeling indices was 56.2% and 36.3%, respectively. IDC with a large central acellular zone presenting with characteristic MRI should be noted as a new morphological entity.

The usefulness of Tc-99m MIBI for evaluating brain tumors: comparative study with Tl-201 and relation with P-glycoprotein

PURPOSE: This study was undertaken to determine the usefulness of Tc-99m methoxyisobutylisonitrile (MIBI) in brain tumors compared with TI-201 imaging. The authors evaluated the correlation between MIBI uptake and the presence of P-glycoprotein, and also the relation between MIBI uptake in response to combined radiotherapy and chemotherapy in glioblastoma. MATERIALS AND METHODS: Thirty-four brain tumors composed of 15 glioblastoma multiforme (GBM), 5 anaplastic astrocytomas, 5 low-grade astrocytomas, and 9 metastases were evaluated. Early and delayed images were obtained for MIBI and Tl-201 scintigraphy. P-glycoprotein status in all GBM, 2 anaplastic astrocytomas, 2 low-grade astrocytomas, and 2 metastases were evaluated immunohistochemically. Patients with GBM were divided into an effective and a noneffective group according to the change in tumor size. MIBI uptake indices were compared for these two groups. RESULTS: Both radiopharmaceuticals accumulated in all GBM and anaplastic astrocytomas. In low-grade astrocytomas, only one case showed tracer uptake. In metastasis, two cases showed high uptake on early images and marked washout on delayed images. Uptake ratio values (early uptake ratio and delayed uptake ratio) in all tumors were significantly higher in MIBI than in Tl-201. Immunohistochemical studies showed that the metastases were positive for P-glycoprotein but the GBM were not. In low-grade astrocytomas, a few cells were positively stained. In relation to the therapeutic outcome of GBM, both the early and delayed uptake ratios of MIBI were significantly greater in the noneffective group. CONCLUSIONS: Although diagnostic ability was comparable in MIBI and Tl-201, the imaging quality was better in MIBI. Both radiopharmaceuticals are useful in differentiating low-grade glioma from high-grade glioma. MIBI delayed imaging could also reflect the presence of P-glycoprotein. Intense MIBI uptake was also predictive of a poor clinical outcome in GBM.

Accumulation of 4- and 5-ene steroid sulfates in human breast cyst fluids.

Gross cystic disease of the breast is one of the most common diseases of adult females. Breast cyst fluid contains various steroid hormones. In order to obtain more information about the concentrations of 4- and 5-ene steroids in human breast cyst fluids, levels of pregnenolone sulfate (PREGS), pregnenolone (PREG), dehydroepiandrosterone sulfate (DHEAS) and dehydroepiandrosterone (DHEA) were determined by high-performance liquid chromatography (HPLC). A total of 35 human breast cyst fluid samples, obtained from 35 patients (28-54 years old) were analyzed. Cyst fluid electrolytes were simultaneously determined. Levels of PREGS (mean+/-S.D.) were 26.9+/-20.0 micromol/l (N=35) and of PREG were <0.1 micromol/l. Levels of DHEAS and DHEA were 89.1+/-111.7 micromol/l (N=35) and 0.3+/-0.2 micromol/l (N=35), respectively. Cyst fluids were divided into two groups (types I and II) according to their electrolyte ratio (K(+)/Na(+)). The cysts of the type I group (K(+)/Na(+) >1.5) contained significantly higher levels of PREGS (39.9+/-21.1 micromol/l) and DHEAS (133.2+/-87.9 micromol/l) than those of the type II group (K(+)/Na(+) <1.5), the mean levels of which were 19.8+/-16.2 micromol/dl for PREGS, and 36.3+/-29.0 micromol/dl for DHEAS (P<0.05). PREGS and DHEAS levels in the cysts were significantly correlated (r=0.49; P<0.01). Human breast cyst fluids contain high concentration of DHEAS and PREGS, especially in the cyst fluids containing high K(+)/Na(+) ratios.

Retention of Tc-99m ECD in delayed SPECT of the brain

We determined the effect of retention on the changes in regional biodistribution of Tc-99m ECD in the brain. A total of 14 cases, 7 normal volunteers and 7 patients with various diagnoses but with very minimal radiologic findings or none were included in the study. SPECT images were taken at 30 min, 1, 2, 3, 4 and 6 hrs after an intravenous injection. Retention rates were calculated in various regions and were corrected according to the time decay of technetium. There was a tendency for the retention rate to increase up to three hours of imaging and then a decrease was noted in most regions of the brain. In the thalamus, increasing retention was noted. In conclusion, Tc-99m ECD retention in the different regions of the brain varies with time. These differences should always be considered when planning and interpreting SPECT quantitative studies.

Computer-Aided Diagnosis (CAD) for Mammography: Preliminary Results.

PurposeTo evaluate the CAD system for screening mammograms.Materials and MethodsMammograms of patients with asymptomatic breast cancer were examined retrospectively. A total of 260 screening mammograms from 65 patients (bilateral cranio-caudal and medio-lateral-oblique views from each) were tested by using the CAD system (ImageChecker M1000 system, R2 Technology, Los Altos, CA, USA).ResultsWith 0.58 microcalcifications marks/film and 0.20 mass marks/film set as the false positive rate, 100% of microcalcifications cases and 79% of mass cases were detected correctly.ConclusionThe CAD system has the potential to become a second reader. Further developments are expected to improve the accuracy of detection of mass lesions.

Amino acid modulation of glucose-induced insulin and glucagon release in diabetic patients.

In order to determine whether amino acids have a beneficial effect on glucose tolerance in diabetes, the effect of intravenous infusion of mixed amino acids on plasma insulin, glucagon, and blood glucose responses to oral glucose loading was studied in patients with mild to moderate diabetes. Intravenous infusion of mixed amino acids over a period of 30 min which was started 30 min or immediately before oral glucose loading significantly augmented the insulin response but did not improve the blood glucose curve, probably due to excessive glucagon response. However, amino acid infusion over a period of 60 min started immediately before oral glucose loading evoked a sustained rise of plasma insulin associated with a lesser degree of glucagon secretion, thus causing significant improvement of the blood glucose curve.