||OKAMOTO M, SASAKI M, SUGIO K, SATO C, IWAMA T, IKEUCHI T, TONOMURA A, SASAZUKI T, MIYAKI M, Loss of constitutional heterozygosity in colon carcinoma from patients with familial polyposis coli (共著), Nature, 10.1038/331273a0, 331, 6153, 273-277, 1988.01.
||M SASAKI, M OKAMOTO, C SATO, K SUGIO, J SOEJIMA, T IWAMA, T IKEUCHI, A TONOMURA, M MIYAKI, T SASAZUKI, LOSS OF CONSTITUTIONAL HETEROZYGOSITY IN COLORECTAL TUMORS FROM PATIENTS WITH FAMILIAL POLYPOSIS COLI AND THOSE WITH NONPOLYPOSIS COLORECTAL-CARCINOMA, CANCER RESEARCH, 49, 16, 4402-4406, 1989.08.
||M SASAKI, K SUGIO, T SASAZUKI, K-RAS ACTIVATION IN COLORECTAL TUMORS FROM PATIENTS WITH FAMILIAL POLYPOSIS-COLI, CANCER, 65, 11, 2576-2579, 1990.06.
||M SASAKI, Y ICHIYA, Y KUWABARA, M OTSUKA, T FUKUMURA, Y KAWAI, H KOGA, K MASUDA, FLUORINE-18-FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY IN TECHNETIUM-99M-HYDROXYMETHYLENEDIPHOSPHATE NEGATIVE BONE-TUMORS, JOURNAL OF NUCLEAR MEDICINE, 34, 2, 288-290, 1993.02, We have encountered two cases of bone tumors with high F-18-fluorodeoxyglucose (FDG) uptake and negative Tc-99m-HMDP bone scintigraphy, including a patient with myeloma and a patient with a metastatic bone tumor from esophageal cancer. Bone scintigraphy with a Tc-99m-phosphate complex reflects osteoblastic activity in the bone tissue surrounding the tumor, whereas the accumulation of FDG is associated with the metabolic activity of the tumor itself. An FDG-PET study can therefore be used as a complementary study for the detection and follow-up of bone tumors when a Tc-99m-phosphate bone scintigram is negative..
||M Sasaki, Y Ichiya, Y Kuwabara, Y Akashi, T Yoshida, T Fukumura, S Murayama, T Ishida, K Sugio, K Masuda, The usefulness of FDG positron emission tomography for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer: A comparative study with X-ray computed tomography, EUROPEAN JOURNAL OF NUCLEAR MEDICINE, 10.1007/BF00843701, 23, 7, 741-747, 1996.07, We evaluated the usefulness of fluorine-18-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) in the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer and then compared the findings with the results of X-ray CT by region based on the histological diagnoses. We examined 29 patients with non-small cell lung cancer. One hundred and thirty-two mediastinal lymph nodes were surgically removed and the histological diagnoses were confirmed, FDG PET images, including 146 mediastinal regions, were visually analysed and the mediastinal lymph nodes were scored as positive when the FDG uptake was higher than that in the other mediastinal structures, On the X-ray CT scans, any mediastinal lymph nodes with a diameter of 10 mm or larger were scored as positive. All three examinations were successfully performed on 71 regions. For FDG PET, we found a sensitivity of 76%, a specificity of 98% and an accuracy of 93%. On the other hand, for X-ray CT a sensitivity of 65%, a specificity of 87% and an accuracy of 82% were observed, A significant difference was observed in respect of both specificity and accuracy (P<0.05). Based on the above findings, FDG PET is suggested to be superior to X-ray CT when used for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer..
||M Sasaki, Y Ichiya, Y Kuwabara, T Yoshida, T Inoue, T Morioka, K Hisada, M Fukui, K Masuda, Hyperperfusion and hypermetabolism in brain radiation necrosis with epileptic activity, JOURNAL OF NUCLEAR MEDICINE, 37, 7, 1174-1176, 1996.07, We report a case of high uptake of C-11-methionine (MET), F-18-FDG (FDG) and Tl-201-CI (Tl) in brain radiation necrosis. Twenty-one years previously, the patient had undergone surgery and radiation therapy consisting of 60-Gy for ependymoma in the anterior horn of the right lateral ventricle. The clinical features consisting of frequent seizures of the left face and arm suddenly appeared 2 wk before admission. MRI depicted a T1- and T2-prolonged lesion in the right frontal lobe. Abnormally high uptake in this area demonstrated by MET-PET, FDG-PET, Tl-SPECT or HMPAO-SPECT suggested the presence of a recurrent tumor. A craniotomy was then performed and an intraoperative electrocorticogram showed continuous epileptic spikes in the lesion. The epileptic foci were resected and the histological features of the lesion were consistent with radiation necrosis. After surgery, the seizures disappeared and the postoperative examinations with MET-PET, FDG-PET, Tl-SPECT and HMPAO-SPECT no longer showed abnormally high uptake. Hypermetabolism and hyperperfusion related to epileptic fits are therefore thought to result in high uptake of MET, FDG and Tl in radiation necrosis..
||M Sasaki, Y Ichiya, Y Kuwabara, T Yoshida, T Fukumura, K Masuda, Benzodiazepine receptors in chronic cerebrovascular disease: Comparison with blood flow and metabolism, JOURNAL OF NUCLEAR MEDICINE, 38, 11, 1693-1698, 1997.11, The brain benzodiazepine (BZD) receptor distribution in patients with chronic cerebrovascular disease was assessed with I-123-iomazenil (IMZ) SPECT, and the findings were compared with the data for the cerebral blood flow (CBF) and cerebral metabolism. Methods: We examined nine patients with chronic cerebrovascular diseases, six patients with cerebral infarction and three with moyamoya disease. Iodine-123-IMZ SPECT images were obtained for 15 min, 3 hr after the administration of 167 or 222 MBq I-123-IMZ. In seven patients, the CBF and oxygen metabolism were measured by the O-15 steady-state method. In two patients, the CBF and glucose metabolism were measured by Tc-99m-HMPAO SPECT and F-18-fluoro-2-deoxy-D-glucose-PET, respectively. The brain was initially classified into 18 regions, and abnormalities in the BZD receptor distribution, CBF and cerebral metabolism were visually evaluated. The count ratio of lesion-to-contralateral normal region (L-to-C ratio) was then used for comparison. Results: In the core of the infarct, the I-123-IMZ uptake decreased (L-to-C ratios of the blood flow 0.42 +/- 0.26; metabolism 0.45 +/- 0.24; and I-123-IMZ uptake 0.46 +/- 0.14). In the peri-infarct region, the I-123-IMZ uptake slightly decreased (L-to-C ratios of 0.81, 0.82 and 0.89, respectively). In the region of misery perfusion, the I-123-IMZ uptake was preserved (L-to-C ratios of 0.73, 1.07 and 1.02, respectively). In the remote deafferentated areas in the ipsilateral cerebrum, the I-123-IMZ uptake was preserved (L-to-C ratios of 0.76 +/- 0.10, 0.75 +/- 0.04 and 0.98 +/- 0.05, respectively). In the remote areas in the contralateral cerebellum, the I-123-IMZ uptake was preserved (L-to-C ratios of 0.84 +/- 0.08, 0.85 +/- 0.04 and 0.94 +/- 0.05, respectively). Conclusion: The BZD receptor distribution, as measured by I-123-IMZ SPECT, is not considered to reflect neuronal function, but it may reflect neuronal cell viability. Iodine-123-IMZ SPECT may, therefore, hold promise as a potential probe for neuronal damage..
||M Sasaki, Y Kuwabara, T Yoshida, T Fukumura, T Morioka, S Nishio, M Fukui, K Masuda, Carbon-11-methionine PET in focal cortical dysplasia: A comparison with fluorine-18-FDG PET and technetium-99m-ECD SPECT, JOURNAL OF NUCLEAR MEDICINE, 39, 6, 974-977, Vol.39,No.6,pp.974 - 977, 1998.06, Focal cortical dysplasia is one of the known neuronal migration disorders and has recently been recognized as a cause of intractable epilepsy. in this study, we assessed the (11)C-methionine (MET) uptake in focal cortical dysplasia by PET, and then compared the results with that of (18)F-fluoro-2-deoxy-D-glucose (FDG) PET and (99m)Tc-ethyl cysteinate dimer (ECD) SPECT. Methods: Four patients (3 men, 1 woman; age range 16-68 yr) were examined by PET and SPECT for a presurgical examination of medically intractable seizures. In all 4 patients, (11)C-MET PET was performed for 15 min, started 15 min after the administration of 511-662 MBq MET. In 3 of 4 patients, FDG PET was performed for 15 min, and started 20 min after the administration of 185-370 MBq FDG. In all 4 patients, the cerebral blood flow was also evaluated by (99m)Tc-ECD SPECT for 15 min after the administration of 600 MBq ECD. Results: In MET PET, all 4 lesions were visually recognized to have high MET uptake areas. The MET uptake of the lesions was 1.44 +/- 0.30 for the standardized uptake value (SUV) (ranging from 0.99-1.61). In FDG PET, 2 lesions were demonstrated to have low uptake areas (3.82 in SUV) while I had an ictal high uptake (4.74 in SUV). In ECD SPECT, 1 lesion demonstrated hypoperfusion and I ictal hyperperfusion while 2 showed no abnormalities. All 4 patients underwent a cortical resection and the microscopic examinations were consistent with those of focal cortical dysplasia but no evidence of a tumor was found. Conclusion: MET PET is useful for identifying focal cortical dysplasia as a high uptake area..
||M Sasaki, Y Kuwabara, T Yoshida, M Nakagawa, T Fukumura, F Mihara, T Morioka, M Fukui, K Masuda, A comparative study of thallium-201 SPET, carbon-11 methionine PET and fluorine-18 fluorodeoxyglucose PET for the differentiation of astrocytic tumours, EUROPEAN JOURNAL OF NUCLEAR MEDICINE, 10.1007/s002590050294, 25, 9, 1261-1269, Vol.25,No.9,pp.1262 - 1269, 1998.09, Thallium-201, carbon-ii methionine (MET) and fluorine-18 fluorodeoxyglucose (FDG) have all been used to assess brain tumours. The aim of this study was to determine which of these tracers are of use for evaluating the histological grade and the extent of astrocytoma. Tl-201 single-photon emission tomography (SPET), MET positron emission tomography (PET) and FDG PET were all performed in 23 patients (13 men, 10 women) with newly diagnosed astrocytic rumours [seven with astrocytoma (grade II), ten with anaplastic astrocytoma (grade III) and six with glioblastoma (grade IV)]. The Tl-201 uptake of the rumours was evaluated by a lesion-to-normal region count ratio. Both MET and FDG uptake of the tumours was evaluated by a semiquantitative analysis using the standardized uptake value. Tl-201 uptake was found to increase in rank order with histological grade and was significantly different among the three groups (grade II: 1.51+/-0.36; grade III: 2.58+/-1.50; grade IV: 7.65+/-3.84). MET uptake in grade II (1.49+/-0.44) was also significantly lower than that in both grade III (3.29+/-1.44) and grade IV (3.20+/-0.92). FDG uptake was not significantly different among the three groups (grade II: 2.90+/-0.45; grade III: 3.86+/-1.56; grade IV: 3.57+/-0.83). No significant correlation was observed between Tl-201 uptake and either MET uptake or FDG uptake. In most patients, the extent of the increased MET uptake was the largest while that of the increased FDG uptake was the smallest. In patients with positive Tl-201 uptake, the extent of the Tl-201 uptake was equal to or smaller than that of gadolinium enhancement. For evaluation of histological grade of astrocytic tumours. Tl-201 is therefore considered to be useful though the Tl-201 uptake in some grade III astrocytomas was not different from that in grade II astrocytomas. MET was found to be highly useful for detecting astrocytomas, for differentiating between benign and malignant astrocytomas, and for evaluating the extent of astrocytomas; however, it was not sufficiently useful permit evaluation of the histological grade. FDG was not found to be useful either for evaluating the histological grade or for differentiating: between benign and malignant astrocytomas..
||M Sasaki, Y Kuwabara, Y Ichiya, Y Akashi, T Yoshida, M Nakagawa, S Murayama, K Masuda, Differential diagnosis of thymic tumors using a combination of C-11-methionine PET and FDG PET, JOURNAL OF NUCLEAR MEDICINE, 40, 10, 1595-1601, 1999.10, We assessed the usefulness of PET studies in making a differential diagnosis of thymic tumors by using C-11-methionine (MET) and F-18-fluorodeoxyglucose (FDG). Methods: We examined 31 patients with thymic tumors, including 14 patients with thymic cancer, 9 with invasive thymoma, 5 with noninvasive thymoma and 3 with thymic cysts. The histological diagnosis was confirmed by either surgery or biopsy. MET PET and FDG PET were performed in 28 and 29 patients, respectively. Both the MET and FDG uptakes were evaluated by the standardized uptake value (SUV). Results: MET uptake was not substantially different among thymic cancer (4.8 +/- 1.4), invasive thymoma (4.3 +/- 1.1) and noninvasive thymoma (4.5 +/- 1.2), but MET uptake in thymic cysts (0.9 +/- 0.1) was lower than that in the other three tumors (P < 0.01). The FDG uptake in thymic cancer (7.2 +/- 2.9) was higher than that in invasive thymoma (3.8 +/- 1.3), noninvasive thymoma (3.0 +/- 1.0) and thymic cysts (0.9) (P < 0.01). MET uptake in thymic tumors correlated with the FDG uptake (r = 0.65), whereas MET uptake in thymic cancer was tower than FDG uptake (FDG/MET ratio = 1.52 +/- 0.52) but was higher than FDG uptake in both invasive and noninvasive thymoma (FDG/MET ratio = 0.86 +/- 0.33), To differentiate thymic cancer from thymoma, a receiver operating characteristic (ROC) analysis was performed. The area under the curve of FDG PET was 0.90, whereas the FDG/MET ratio was 0.87. Conclusion: The MET PET, FDG PET and the FDG/MET ratios were unable to differentiate benign thymic tumors from malignant ones, although FDG PET was considered to be useful in the differential diagnosis between thymic cancer and thymoma. Although the difference in the uptake ratio between FDG and MET suggests a different origin of the tumors, the FDG/MET ratio is not considered to be useful as a complementary method for the differential diagnosis of thymic tumors..
||Sasaki M, Kuwabara, Y, Ichiya, Y, Yoshida, T, Nakagawa, M, Soeda, H, Sugio, K, Maehara, Y, Masuda, Prediction of the chemosensitivity of lung cancer by 99mTc-hexakis-2-methoxyisobutyl isonitrile SPECT, J Nucl Med, 40, 11, 1778-1783, Vol.40,No.11,pp.1778 - 1783, 1999.11.
||Sasaki M, Fukumura T, Kuwabara Y, Yoshida T, Nakagawa M, Ichiya Y, Masuda K, Biodistribution and breast tumor uptake of 16α-[18F]-fluoro-17β-estradiol in rat, Ann Nucl Med, 10.1007/BF02988592, 14, 2, 127-130, Vol.14,No.2,pp.127 - 130, 2000.02.
||M Sasaki, Y Kuwabara, H Koga, M Nakagawa, T Chen, K Kaneko, K Hayashi, K Nakamura, K Masuda, Clinical impact of whole body FDG-PET on the staging and therapeutic decision making for malignant lymphoma, ANNALS OF NUCLEAR MEDICINE, 10.1007/BF02988618, 16, 5, 337-345, 16 (5): 337 - 345, 2002.07, Objectives: The aim of this study is to evaluate the clinical impact of whole-body FDG-PET for the pre-therapeutic evaluation of malignant lymphoma and compared to that of Ga-67-scintigraphy when added to non-RI examinations. Methods: We examined 46 patients with malignant lymphoma including 42 newly diagnosed cases and 4 relapsed cases. Whole-body FDG-PET was started 63 minutes after the administration of FDG with ECAT EXACT HR+. The clinical stage of each patient was determined based on the results of a non-RI examination (consisting of physical examination, CT, gastrointestinal studies and bone marrow aspiration), Ga-67 planar images and FDG-PET. Discrepant findings were verified based on the response to treatment and the findings of a follow-up examination more than 6 months after treatment. Finally, 152 nodal regions and 19 extranodal tissues were found to be involved by disease. Results: In the 152 nodal lesions, FDG-PET detected 54 nodal lesions in addition to 98 lesions detected by non-RI examinations, whereas Ga-67-scintigraphy detected 14 additional lesions. The sensitivity of non-RI, non-RI + Ga-67 and non-RI + FDG was 64.5%, 73.7% and 100.0%, respectively. In 19 extranodal lesions, FDG-PET detected 5 extranodal lesions in addition to 13 lesions detected by non-RI examinations, whereas Ga-67-scintigraphy detected I additional lesion. The sensitivity of non-RI, non-RI + 67Ga and non-RI + FDG was 68.4%,73.7% and 94.7%, respectively. When combining the FDG-PET findings with the non-RI findings, the improvement of the detectability was much higher than that when 67Ga findings were combined to the non-RI findings. For the staging of lymphoma, the non-RI and non-RI + 67Ga findings accurately diagnosed 76.1% and 80.4%, respectively, whereas the non-RI + FDG findings accurately diagnosed 82.6%. Finally, FDG-PET resulted in changes in the clinical management of 8 patients (17.4%). Conclusions: FDG-PET offers more information in addition to the findings of conventional diagnostic methods than 67Ga-scintigraphy in order to accurately detect malignant lymphoma. FDG-PET can therefore play an important role in therapeutic decision making on lymphoma..
||Sasaki M, Sugio K, Kuwabara Y, Koga H, Nakagawa M, Chen T, Kaneko K, Hayashi K, Shioyama Y, Sakai S, Honda H, Alterations of tumor suppressor genes (Rb, p16, p27 and p53) and increased FDG uptake in lung cancer, Annals of Nuclear Medicine, 10.1007/BF02990021, 17, 3, 189-196, 17 (3): 189 - 196, 2003.05.
||Improvement in PET/CT image quality with a combination of point-spread function and time-of-flight in relation to reconstruction parameters..
||Go Akamatsu, Masayuki Sasaki, Influences of point-spread function and time-of-flight reconstructions on standardized uptake value of lymph node metastases in FDG-PET, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2013.09.030, 83, 1, 226-230, 2014.01.
||Maebatake A, Sato M, Kagami R, Yamashita Y, Komiya I, Himuro K, Shingo Baba, Masayuki Sasaki, An anthropomorphic phantom study of brain dopamine transporter SPECT images obtained using different SPECT/CT devices and collimators., J Nucl Med Technol, 43, 1, 41-46, 2015.03.
||Yabuuchi H, Masayuki Sasaki, Hiroshi Honda, Anterior mediastinal solid tumours in adults: characterisation using dynamic contrast-enhanced MRI, diffusion-weighted MRI, and FDG-PET/CT, CLINICAL RADIOLOGY, 10.1016/j.crad.2015.07.004, 70, 11, 1289-1298, 2015.11.
||Automated PET-only quantification of amyloid deposition with adaptive template and empirically pre-defined ROI..
||Toshioh Fujibuchi, Takatoshi Toyoda, Shingo Baba, Yoshiyuki Umezu, Isao Komiya, Masayuki Sasaki, Hiroshi Honda, Evaluation of the distribution of activation inside a compact medical cyclotron, Applied Radiation and Isotopes, 10.1016/j.apradiso.2017.02.045, 124, 27-31, 2017.06, The distribution of activation inside a compact medical cyclotron was evaluated by measuring 1 cm dose equivalent rates and γ-ray spectra. Analysis of the distribution of activation showed high activation at the deflector and the magnetic channel. Radionuclides 60Co, 57Co, 65Zn, and 54Mn were detected. Different radionuclides were generated from different components of the cyclotron, and low-activity radionuclides could be detected under low-background-radiation conditions..
||Shinji Amakusa, Koki Matsuoka, Masayuki Kawano, Kiyotaka Hasegawa, Mio Ouchida, Ayaka Date, Tsuyoshi Yoshida, Masayuki Sasaki, Influence of region-of-interest determination on measurement of signal-to-noise ratio in liver on PET images, Annals of Nuclear Medicine, 10.1007/s12149-017-1215-y, 32, 1, 2018.01, Objective: On 18F-fluoro-2-deoxy-d-glucose (18F-FDG) positron emission tomography (PET), signal-to-noise ratio in the liver (SNRliver) is used as a metric to assess image quality. However, some regions-of-interest (ROIs) are used when measuring the SNRliver. The purpose of this study is to examine the different ROIs and volumes of interest (VOIs) to obtain a reproducible SNRliver. Methods: This study included 108 patients who underwent 18F-FDG-PET/CT scans for the purpose of cancer screening. We examined four different ROIs and VOIs; a 3-cm-diameter and a 4-cm-diameter circular ROI and a 3-cm-diameter and a 4-cm-diameter spherical VOI on the right lobe of the patients’ livers. The average of SUV (SUVmean), standard deviation (SD) of SUV (SUVSD), SNRliver and SD of the SNRliver obtained using ROIs and VOIs were then compared. Results: Although the SUVmean was not different among the ROIs and VOIs, the SUVSD was small with a 3-cm-diameter ROI. The largest SUVSD was obtained with a 4-cm-diameter spherical VOI. The SNRliver and the SD of the SNRliver with a 4-cm-diameter spherical VOI were the smallest, while those with a 3-cm-diameter circular ROI were the largest. These results suggest that a small ROI may be placed on a relatively homogeneous region not representing whole liver unintentionally. Conclusion: The SNRliver varied according to the shape and size of ROIs or VOIs. A 4-cm-diameter spherical VOI is recommended to obtain stable and reproducible SNRliver..
||Multicentre analysis of PET SUV using vendor-neutral software: the Japanese Harmonization Technology (J-Hart) study..
||Hashimoto N, Morita K, Tsutsui Y, Himuro K, Baba S, Sasaki M., Time-of-flight information improved the detectability of sub-centimeter sphere using clinical positron emission tomography/computed tomography scanner., J Nucl Med Technol., 10.2967/jnmt.117.204735., 39, 10, 268-273, J Nucl Med Technol. 2018 Sep;46(3):268-273., 2018.09.
||Yuma Tsubaki, Go Akamatsu, Natsumi Shimokawa, Suguru Katsube, Aya Takashima, Masayuki Sasaki, Development and evaluation of an automated quantification tool for amyloid PET images, EJNMMI Physics, 10.1186/s40658-020-00329-4, 7, 1, 2020.12, Abstract
Quantitative evaluation of amyloid positron emission tomography (PET) with standardized uptake value ratio (SUVR) plays a key role in clinical studies of Alzheimer’s disease (AD). We have proposed a PET-only (MR-free) amyloid quantification method, although some commercial software packages are required. The aim of this study was to develop an automated quantification tool for amyloid PET without using commercial software.
The quantification tool was created by combining four components: (1) anatomical standardization to positive and negative templates using NEUROSTAT stereo.exe; (2) similarity calculation between standardized images and respective templates based on normalized cross-correlation (selection of the image for SUVR measurement); (3) voxel value normalization by the mean value of reference regions (making an SUVR-scaled image); and (4) SUVR calculation based on pre-defined regions of interest (ROIs). We examined 166 subjects who underwent a [11C] Pittsburgh compound-B PET scan through the Japanese Alzheimer’s Disease Neuroimaging Initiative (J-ADNI) study. SUVRs in five ROIs (frontal lobe, temporal lobe, parietal lobe, occipital lobe, and posterior cingulate cortex and precuneus) were calculated with the cerebellar cortex as the reference region. The SUVRs obtained by our tool were compared with manual step-by-step processing and the conventional PMOD-based method (PMOD Technologies, Switzerland).
Compared with manual step-by-step processing, our developed automated quantification tool reduced processing time by 85%. The SUVRs obtained by the developed quantification tool were consistent with those obtained by manual processing. Compared with the conventional PMOD-based method, the developed quantification tool provided 1.5% lower SUVR values, on average. We determined that this bias is likely due to the difference in anatomical standardization methods.
We developed an automated quantification tool for amyloid PET images. Using this tool, SUVR values can be quickly measured without individual MRI and without commercial software. This quantification tool may be useful for clinical studies of AD.