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Mototaka Miyake

Publications and source records attributed to Mototaka Miyake.

11 recordsLinked to original sources
PubMed2006

CT and MRI findings in KIT-weak or KIT-negative atypical gastrointestinal stromal tumors.

The large majority of gastrointestinal stromal tumors (GIST) can be diagnosed on the basis of KIT immunoreactivity. However, some atypical tumors show weak or negative KIT expression. We studied the imaging characteristics of atypical GIST, reviewing CT and MRI findings in ten patients (eight men, two women; mean age 59 years) with atypical GIST. Radiological studies were evaluated by two radiologists by consensus and included CT and MR imaging in all patients. Pathological diagnoses were made from surgery and confirmed by the polymerase-chain reaction (PCR) to amplify both exons of the c-kit gene and PDGFRA gene. The CT and MR examinations revealed a heterogeneous mass of the stomach containing cystic regions and soft tissue elements in all cases. All lesions were extraluminal masses and had an exophytic epicenter. On T1-weighted MR images soft tissue elements of the tumors were of homogeneously low- (n=3) or iso-signal intensity (n=7) compared with the liver parenchyma. On fast spin-echo T2-weighted MR images soft tissue elements of all tumors showed cystic regions of significantly high signal intensity interspersed with septumlike structures of low signal intensity. All lesions exhibited homogeneously (n=4) or heterogeneously (n=6) mild to moderate enhancement of soft tissue elements. Despite the relatively small number of patients CT and MRI findings of atypical GIST are a submucosal mass with soft tissue elements and cystic regions.

Aged↗
PubMed2006

A case of ganglioneuroma presenting abnormal FDG uptake.

We report a case of ganglioneuroma with abnormal 18F-fluorodeoxyglucose (FDG) uptake. A 26-year-old woman presented to the hospital with a slowly growing abdominal tumor without symptoms. She was diagnosed with neuroblastoma in childhood and treated by surgery and chemotherapy. Computed tomography (CT) revealed huge retroperitoneal tumors and fused 18F-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT image showed abnormal accumulation of FDG in tumors with maximal standardized uptake value of 2.02. Considering her past history, ganglioneuroma matured from neuroblastoma was considered, the most likely diagnosis. However, a second primary malignant tumor, such as malignant peripheral nerve sheath tumor arising in ganglioneuroma, could not be ruled out. Then, an excisional biopsy was performed and the diagnosis of mature ganglioneuroma was made. Pathological investigation may be needed to differentiate ganglioneuroma from other malignant tumors and, therefore, FDG-PET/CT findings can be helpful for biopsy planning.

Abdominal Neoplasms↗
PubMed2006

Diaphyseal medullary stenosis with pleomorphic malignant fibrous histiocytoma of the bone: 99mTc hydroxymethylenediphosphonate and 201Tl chloride scintigraphy findings.

Diaphyseal medullary stenosis (DMS) is an extremely rare hereditary bone dysplasia, which was first described by Arnold in 1973. DMS has a high incidence of pleomorphic malignant fibrous histiocytoma (MFH). In this paper, we report the imaging findings of DMS with pleomorphic MFH of the bone, mainly describing 99mTc hydroxymethylenediphosphonate (HMDP) and thallium-201 (201Tl) chloride scintigraphy findings. On 99mTc HMDP scintigraphy, focal increased uptake area of the right femur corresponded to the area of bone marrow invasion of the tumor and bone infarction. The mechanism of the uptake of 99mTc HMDP to the extraosseous lesion was not clear. On 201Tl chloride scintigraphy, the increased uptake of the periphery of the mass seemed to reflect the aggressiveness of invasion and the cellularity.

Adult↗
PubMed2006

CT and MRI features of low-grade fibromyxoid sarcoma in the shoulder of a pediatric patient.

We report the computed tomography (CT) and magnetic resonance imaging (MRI) features of a 10-year-old boy with low-grade fibromyxoid sarcoma (LGFMS) in the shoulder and correlate them with the clinicopathological features. LGFMS, a rare soft tissue sarcoma with bland histological features and paradoxically aggressive behavior, tends to occur in superficial regions and in children more than previously recognized. To date, few imaging studies have been reported, particularly in pediatric patients. In this case, precontrast CT showed a low- to isodensity mass and punctate calcification. On contrast-enhanced CT, heterogeneous enhancement was seen. MRI findings correlated well with the pathological features of the tumor. The myxoid area showed high signal intensity on T2-weighted MR images and heterogeneous enhancement after administration of contrast material; the hypercellular area demonstrated lower signal intensity on T2-weighted MR images and slight enhancement.

Child↗
PubMed2005

Sclerosing perineurioma: Tumor of the hand with a short T2.

We present two cases of sclerosing perineurioma, a rare soft tissue tumor, in the palm and the ring finger respectively, presenting as a small, painless and subcutaneous mass. This tumor has a predilection for the digits and palms of young, predominantly male adults. In the present cases the tumors showed very low signal intensity on T2-weighted magnetic resonance (MR) images. Histologically they contained abundant collagen and hyalinized stroma, which would account for areas of low signal intensity on T2-weighted MR images. Immunohistochemically, the tumor cells were positive for vimentin, epithelial membrane antigen and human erythrocyte glucose transporter 1 and negative for S-100 protein. To the best of our knowledge, the appearance of sclerosing perineurioma on MR imaging has not been previously reported in the English-language literature. Sclerosing perineurioma should be considered in the differential diagnosis of hand tumors when the tumor shows low signal intensity on T2-weighted MR images.

Adolescent↗
PubMed2005

Pulmonary involvement of malignant melanoma: thin-section CT findings with pathologic correlation.

OBJECTIVES: The purpose of this study was to characterize the thin-section computed tomography (CT) findings of primary and secondary pulmonary malignant melanoma and to correlate them with the histopathologic features. MATERIALS AND METHODS: Patients were identified from a pathologic registration system database through a query for patients with diagnosed primary or secondary pulmonary melanoma who had undergone surgical resection. A total of 19 pulmonary malignant melanomas, including one primary and 18 secondary involvements, from 10 patients were enrolled into this study. The patients consisted of 3 men and 6 women, with a mean age of 55 years (range, 28 to 71 years). Thin-section CT findings evaluated by consensus between two radiologists were compared with the histopathologic specimens. RESULTS: Tumor size ranged from 4 to 62 mm (mean, 19 mm) on thin-section CT images. Four characteristic patterns including solitary or multiple solid nodule, endobronchial lesion, cavitary nodule, and nodule with ground-glass attenuation were disclosed by correlation between thin-section CT and pathologic findings. The most common thin-section CT finding was a solid nodule with a well-defined, smooth margin (n=14). Endobronchial lesions were seen in one primary and one secondary involvement (n=2). Less common CT findings were cavitary nodule (n=1) and nodule with ground-glass attenuation (n=1). CONCLUSION: Primary and secondary pulmonary malignant melanomas show various patterns of involvement on thin-section CT.

Adult↗
PubMed2005

MR features of angiosarcoma in a patient with Maffucci's syndrome.

Maffucci's syndrome is a rare sporadic congenital disorder associated with multiple enchondromas and soft tissue hemangiomas. These bone and soft tissue tumors have the potential of malignant transformation to various histologic types: chondrosarcoma, osteosarcoma, fibrosarcoma, and angiosarcoma. We report a rare case of Maffucci's syndrome with soft tissue angiosarcoma of the leg to illustrate MRI findings with pathologic correlations.

Adolescent↗
PubMed2005

Pulmonary lymphangioleiomyomatosis in a male patient with tuberous sclerosis complex.

Pulmonary lymphangioleiomyomatosis (LAM) is a rare disease of unknown etiology that occurs almost exclusively in women of reproductive age. High-resolution computed tomography (HRCT) reveals the striking feature of diffuse cystic changes throughout the lung parenchyma. The correct diagnosis may be delayed by several years after the onset of symptoms because of the rarity of the disease and the need for chest CT scans to identify the lung involvement. We describe a case of pulmonary LAM in a male patient associated with tuberous sclerosis complex (TSC), in whom the early stage of disease could be depicted by chest HRCT scans.

Adolescent↗