| 1. |
Yabuuchi H, Kamitani T, Sagiyama K, Yamasaki Y, Hida T, Matsuura Y, Hino T, Murayama Y, Yasumatsu R, Yamamoto H, Characterization of parotid gland tumors: added value of permeability MR imaging to DWI and DCE-MRI, EUROPEAN RADIOLOGY, 10.1007/s00330-020-07004-3, 30, 12, 6402-6412, 2020.12, Objectives: To determine added value of permeability MRI in parotid tumor characterization to T2-weighted imaging (T2WI), semi-quantitative analysis of time-intensity curve (TIC), and intra-voxel incoherent motion diffusion-weighted imaging (IVIM-DWI).
Methods: This retrospective study was approved by the institutional review board, and the informed consent was waived. Sixty-one parotid tumors in 61 patients were examined using T2WI, IVIM-DWI, and permeability MRI. TIC patterns were categorized as persistent, washout, or plateau. Signal intensity ratio of lesion-to-muscle on T2WI, apparent diffusion coefficients (ADCs), D and f values from IVIM-DWI, and Ktrans, kep, Ve, and Vp values from permeability MRI were measured. Multiple comparisons were applied to determine whether any differences among 4 histopathologic types (pleomorphic adenomas, Warthin's tumors, other benign tumors, and malignant tumors) existed. Diagnostic accuracy was compared before and after modification diagnosis referring to permeability MRI. In a validation study, 60 parotid tumors in 60 patients were examined.
Results: ADC and D values of malignant tumors were significantly lower than those of benign tumors other than Warthin's tumors, but higher than those of Warthin's tumors. kep and Vp values of Warthin's tumors were significantly higher than those of malignant tumors. Multivariate analyses showed that TIC pattern, D, and kep values were suitable parameters. McNemar's test showed a significant increase of sensitivity (11/12, 92%) and specificity (46/49, 94%) with adding kep. The validation study yielded high sensitivity (14/16, 88%) and specificity (41/44, 93%).
Conclusion: Permeability MRI offers added value to IVIM-MRI and semi-quantitative TIC analysis of DCE-MRI in characterization of parotid tumors KEY POINTS: • Permeability MR imaging offers added value in the characterization of parotid gland tumors in combination with semi-quantitative TIC analysis and IVIM analyses with D parameter. • The combination of TIC pattern, D, and kep might facilitate accurate characterization of parotid gland tumor, thereby avoiding unnecessary surgery for benign tumors or delayed treatment for malignant tumors. • A combination of permeability and diffusion MR imaging can be used to guide the selection of an appropriate biopsy site.. |
| 2. |
Yabuuchi H, Kawanami S, Iwama E, Okamoto I, Kamitani T, Sagiyama K, Yamasaki Y, Honda H., Prediction of Therapeutic Effect of Chemotherapy for NSCLC Using Dual-Input Perfusion CT Analysis: Comparison among Bevacizumab Treatment, Two-Agent Platinum-based Therapy without Bevacizumab, and Other Non-Bevacizumab Treatment Groups., Radiology, 10.1148/radiol.2017162204., 286, 2, 685-695, 2018.02, Purpose: To determine whether dual-input perfusion computed tomography (CT) can predict therapeutic response and prognosis in patients who underwent chemotherapy for non–small cell lung cancer (NSCLC).
Materials and Methods: The institutional review board approved this study and informed consent was obtained. Sixty-six patients with stage III or IV NSCLC (42 men, 24 women; mean age, 63.4 years) who underwent chemotherapy were enrolled. Patients were separated into three groups: those who received chemotherapy with bevacizumab (BV) (n = 20), those who received two-agent platinum-based therapy without BV (n = 25), and those who received other non-BV treatment (n = 21). Before treatment, pulmonary artery perfusion (PAP) and bronchial artery perfusion (BAP) of the tumors were calculated. Predictors of tumor reduction after two courses of chemotherapy and prognosis were identified by using univariate and multivariate analyses. Covariates included were age, sex, patient's performance status, baseline maximum diameter of the tumor, clinical stage, pretreatment PAP, and pretreatment BAP. For multivariate analyses, multiple linear regression analysis for tumor reduction rate and Cox proportional hazards model for prognosis were performed, respectively.
Results: Pretreatment BAP was independently correlated with tumor reduction rate after two courses of chemotherapy in the BV treatment group (P = .006). Pretreatment BAP was significantly associated with a highly cumulative risk of death (P = .006) and disease progression after chemotherapy (P = .015) in the BV treatment group. Pretreatment PAP and clinical parameters were not significant predictors of therapeutic effect or prognosis in three treatment groups.
Conclusion: Pretreatment BAP derived from dual-input perfusion CT seems to be a promising tool to help predict responses to chemotherapy with BV in patients with NSCLC.. |
| 3. |
Yabuuchi H, Hatakenaka M, Takayama K, Matsuo Y, Sunami S, Kamitani T, Jinnouchi M, Sakai S, Nakanishi Y, Honda H, Non–small cell lung cancer: detection of early response to chemotherapy by Using contrast-enhanced dynamic and diffusionweighted MR Imaging, Radiology, 261, 2, 598-604, 2011.11, Purpose: To evaluate the ability of dynamic contrast material–enhanced and diffusion-weighted (DW) magnetic resonance (MR) imaging to help detect early response to chemotherapy in patients with non–small cell lung cancer (NSCLC).
Materials and Methods: This study was approved by the institutional review board, and written informed consent was obtained from all subjects. Twenty-eight patients with stage IIIB or IV NSCLC (17 women, 11 men; mean age, 64.8 years) who underwent chemotherapy were enrolled. All patients underwent MR imaging before and after the fi rst course of chemotherapy. The time to peak enhancement, maximum enhancement ratio, and washout ratio were determined from the time–signal intensity curves of dynamic contrast-enhanced MR images. The apparent diffusion coeffi cient (ADC) of each lung carcinoma was calculated from DW MR images. The responses of these parameters to the fi rst course of chemotherapy and the pretreatment ADC itself were compared with final tumor size reduction by using the Pearson correlation coeffi cient. Kaplan-Meier curves of progressionfree survival and overall survival were generated, and comparisons between the group with a good response of the signifi cant parameter (upper 50th percentile) and that with a poor response of the signifi cant parameter (lower 50th percentile) were performed by using a two-sided logrank test.
Results: Signifi cant correlation was found only between early ADC change and fi nal tumor size reduction rate ( r 2 = 0.41, P = .00025). The median progression-free survival for the group with a good increase in ADC was 12.1 months, and that for the group with a stable or decreased ADC was 6.67 months ( P = .021), while median overall survival was 22.4 and 12.3 months, respectively ( P = .048).
Conclusion: ADC seems to be a promising tool for monitoring the early response to or predicting prognosis after chemotherapy of NSCLC.. |
| 4. |
Yabuuchi H, Matsuo Y, Sunami S, Kamitani T, Kawanami S, Setoguchi T, Sakai S, Hatakenaka M, Kubo M, Tokunaga E, Yamamoto H, Honda H., Detection of non-palpable breast cancer in asymptomatic women by using unenhanced diffusion-weighted and T2-weighted MR imaging: comparison with mammography and dynamic contrast-enhanced MR imaging., Eur Radiol. , 21, 1, 11-17, 2011.01. |
| 5. |
Yabuuchi H, Matsuo Y, Kamitani T, Setoguchi T, Okafuji T, Soeda H, Sakai S, Hatakenaka M, Kubo M, Tokunaga E, Yamamoto H, Honda H., Non-mass-like enhancement on contrast-enhanced breast MR imaging: Lesion characterization using combination of dynamic contrast-enhanced and diffusion-weighted MR images., Eur J Radiol, 2009.09. |
