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Biomedical subjects

Masayuki Shintaku

Publications and source records attributed to Masayuki Shintaku.

At least 19 recordsLinked to original sources
PubMed2026

Primary Cerebral Pleomorphic-Myxoid Sarcoma With Many Hyaline Globules.

A case of primary sarcoma that arose in the right temporal lobe of a 59-year-old man is reported. The patient had a history of resection of a "pituitary tumor" and postoperative radiotherapy about 40 years earlier. The cerebral tumor consisted of loose and diffuse proliferation of large pleomorphic cells in a matrix showing a markedly myxoid change and containing a variable amount of delicate collagen fibers. Some tumor cells had a large intracytoplasmic vacuole containing acid mucopolysaccharide, thus featuring "pseudolipoblasts." Differentiation along other specific mesenchymal lineages was not found. Many tumor cells contained densely eosinophilic hyaline globules in the cytoplasm. Tumor cells showed a loss of the nuclear expression of H3K27me3. Although cerebral sarcomas showing similar histopathological features have not been previously reported, a markedly myxoid change of the stroma admixed with delicate collagen fibers and "pseudolipoblasts" suggests a close pathological kinship to myxofibrosarcoma. Another notable finding was the appearance of many hyaline globules, which has been considered a characteristic finding of primary intracranial sarcoma, DICER1-mutant. In the cytogenetic study of the present case, however, no DICER1 gene mutations were demonstrated.

Humans↗
PubMed2006

Brain stem lesions in sporadic Creutzfeldt-Jakob disease: a histopathological and immunohistochemical study.

Lesions of the brain stem in sporadic CJD were histopathologically and immunohistochemically investigated using an anti-PrP antibody on ten consecutive autopsy cases. Three major histopathological changes, spongiform changes, neuronal loss and hypertrophic astrocytosis, were employed as parameters of the alterations. The quadrigeminal plate and pontine nuclei were the most severely and consistently affected structures, and immunoreactivity against PrP was seen in these structures. There existed some discrepancies between the severity of the lesions and the intensity of the immunoreactivity against PrP. The medulla oblongata essentially remained normal on histopathological examination, but the inferior olivary nucleus showed prominent PrP deposition. Although the general view that pathological alterations in the brain stem are relatively mild in sporadic CJD was confirmed in this study, lesions of variable degrees which might influence a patient's clinical course were still observed in many structures in the brain stem.

Aged↗
PubMed2006

Chronic superior sagittal sinus thrombosis with phlebosclerotic changes of the subarachnoid and intracerebral veins.

An autopsy case of chronic thrombotic occlusion of the superior sagittal sinus (SSS) with an unusually protracted clinical course is reported. The patient was an 84-year-old man without any predisposing conditions for thrombosis. The clinical features were atypical and were characterized by recurrent cerebral subcortical hemorrhages. The autopsy revealed a large, organized thrombus in the SSS and extensive hemorrhagic infarction of the bilateral parasagittal region of the cerebral hemispheres. The hemorrhagic infarction was comprised of the aggregation of numerous minute foci of coagulation necrosis associated with petechial hemorrhages. Marked phlebosclerotic changes were observed in the subarachnoid and intracerebral veins, which were considered to be reactive changes of the venous walls against a persistent elevation in peripheral venous pressure caused by thrombosis of the SSS.

Aged, 80 and over↗
PubMed2006

Inflammatory myofibroblastic tumor of the uterus with prominent myxoid change.

A surgical case of inflammatory myofibroblastic tumor arising in the uterine corpus and exhibiting prominent myxoid change of the stroma is reported. The patient was a 63-year-old woman with a large tumor mass that filled the uterine cavity and measured 11 cm in maximal dimension. The tumor had a gelatinous appearance and consisted of a loose proliferation of stellate or polygonal cells on a myxomatous background. Fascicular proliferation of spindle cells was also observed focally, and a chronic inflammatory cell infiltration was seen in many areas. Tumor cells had mild atypism and were immunoreactive for vimentin, alpha-smooth muscle actin, and anaplastic lymphoma kinase (ALK). Focal immunoreactivity for high-molecular-weight caldesmon (h-caldesmon) was also noted. The patient has been free from recurrence for 8 months. Inflammatory myofibroblastic tumor of the uterus occasionally shows prominent myxoid change of the stroma, and differentiation from myxoid leiomyosarcoma is problematic in these cases. Based on the immunoreactivity of tumor cells for ALK and h-caldesmon, the present tumor was considered inflammatory myofibroblastic tumor showing a focal phenotypic transition from myofibroblasts to smooth muscle cells.

Actins↗
PubMed2006

Primary choriocarcinoma of the lung manifesting as diffuse alveolar hemorrhage.

An autopsy case of primary pulmonary choriocarcinoma that manifested as diffuse alveolar hemorrhage is reported. A 44-year-old nurse presented with fever, dry cough, hemoptysis, and progressive dyspnea, and died after a downhill course of 2 weeks. Chest radiographs showed diffuse parenchymal shadows throughout the entire lung and a nodular lesion in the right lower lobe. Findings suggestive of acute renal failure were not seen. The autopsy revealed primary pure choriocarcinoma of the right lower lobe and diffuse alveolar hemorrhage throughout the entire lung. Findings of small vessel vasculitis ("pulmonary alveolar capillaritis") were not observed, and extensive neoplastic involvement of the pulmonary vasculature was considered the cause of the diffuse alveolar hemorrhage. Small metastatic foci were found in the liver, adrenal glands, pancreas, and ovaries. This case shows that primary pulmonary neoplasms, on rare occasions, can produce the clinical and pathologic features of diffuse alveolar hemorrhage, probably through elevated pulmonary venous pressure caused by extensive destruction of the vasculature.

Adult↗
PubMed2005

Eosinophilic cytoplasmic inclusions in papillary renal cell carcinoma.

A case of a patient with papillary renal cell carcinoma (RCC) with eosinophilic inclusions is presented. Almost all neoplastic cells contained eosinophilic globules that were stained red by trichrome and were negative for periodic acid-Schiff (PAS) reaction. Immunohistochemically, globules were negative for actin, keratin, vimentin, glially fibrillary acidic protein (GFAP), and neurofilament. Ultrastructurally, globules consisted of electron-dense granular material that is more suggestive of a secretory substance than cytoskeletal filaments. The presence of eosinophilic cytoplasmic inclusions in RCC is rare. In this article, we review similar cases in the literature and discuss the nature of eosinophilic globules.

Aged, 80 and over↗
PubMed2005

Serous cystadenocarcinoma of the pancreas.

A case of serous cystadenocarcinoma of the pancreas in an 85-year-old woman is reported. The tumor extensively involved the body and tail of the pancreas and contiguously invaded the spleen. The histopathology of the tumor was similar to that of serous cystadenoma, but mild nuclear hyperchromatism and atypism were noted, and the neoplastic invasion of nerve fibers in the stroma was observed. In the spleen neoplastic cells forming microcysts were diffusely insinuated in the red pulp without the fibrous stroma. The patient is in good health without recurrence and metastasis after the operation. The present case is the second example of this kind of neoplasm that showed direct splenic invasion. Because serous cystadenocarcinoma of the pancreas exhibits bland cytological features, diligent search for the invasion of the surrounding tissue or peripheral nerves is needed for the differentiation from its benign counterpart.

Aged↗
PubMed2004

Oligodendrocytes within astrocytes ("emperipolesis") in the white matter in Creutzfeldt-Jakob disease.

The occurrence of oligodendrocytes within astrocytes ("emperipolesis") has been described in demyelinating lesions in cases of multiple sclerosis and also in other non-demyelinating disorders. We found that this finding was common in the cerebral white matter of patients with Creutzfeldt-Jakob disease (CJD). Eight consecutive autopsy cases of sporadic CJD were reviewed, and in every case the gray matter exhibited classical histopathological features of CJD. In five cases with a long clinical course, the cerebral white matter was severely involved, and both axons and myelin sheaths were lost markedly. Within this devastated white matter, many hypertrophic astrocytes were found to engulf one to several oligodendrocytes within their cytoplasm (emperipolesis). The oligodendroglial nature of the engulfed cells was corroborated by nuclear immunoreactivity for anti-human Olig 2 antibody. In the remaining three cases, whose clinical course was short, the cerebral white matter was relatively well preserved, and emperipolesis was not or only very rarely found. The prevalence of emperipolesis of this type in the white matter in CJD was well correlated with the severity of the white matter lesions.

Aged↗
PubMed2004

Lymphoproliferative disorders in autoimmune diseases in Japan: analysis of clinicopathological features and Epstein-Barr virus infection.

Lymphoproliferative disorders (LPD) occasionally develop in individuals with immune deficiencies such as immunosuppressive conditions and autoimmune diseases (AID). In our study, the clinicopathologic features and virus status were analyzed in 53 cases with LPD developing in rheumatoid arthritis (RA) and other AID. AID in only 4 of 53 patients had been treated with some sort of immunosuppressive therapy, including methotrexate. Median age at the diagnosis of LPD in AID was 60 years old with marked female predominance (M/F = 0.4). The median interval between the onset of AID and LPD development was 45 months, and longer in RA patients than in other AID (p < 0.01). The primary site of lymphoma was nodal in 21 cases and extra-nodal in 24, with clinical Stage I in 17, II in 5, III in 13, and IV in 13. Immunohistochemistry showed that 39 cases were B cell type, 10 were T cell type and 4 were Hodgkin lymphoma (HL). Then majority of B cell cases were diffuse large B cell lymphomas, and 2 were diffuse polymorphic type. EBER-1 in situ hybridization for Epstein-Barr virus (EBV) showed positive signals in tumor cells in 16 of 53 (30.2%) cases. The EBV-positive rate in T cell LPD (70%) was much higher than that in B cell LPD (12.8%) (p < 0.01). All 4 cases of HL were EBV-positive. Immunohistochemistry showed a latency II pattern of EBV infection (LMP-1(+) and EBNA-2(-)). Five-year overall survival rate was 33%. Multivariate analysis showed that only type of AID was an independent factor for survival of patients, i.e., LPD in RA showed the most favorable prognosis. In conclusion, LPD in AID generally shared common features with sporadic LPD except for a much higher EBV-positive rate in T cell LPD.

Adult↗
PubMed2004

Leiomyosarcoma of the uterus with focal rhabdomyosarcomatous differentiation.

An unusual myometrial tumor was encountered in a 70-year-old female who presented with lower abdominal fullness and symptoms related to pulmonary metastases. Laparotomy revealed a uterine mass that was removed by total abdominal hysterectomy and bilateral salpingo-oophorectomy. Multiple liver metastases also were noted. Pathologic examination of the hysterectomy specimen revealed a 25-cm, well-circumscribed myometrial mass that had a firm, white-to-yellow, focally whorled, sectioned surface with focal hemorrhage and necrosis. Within the main mass was a discrete, 7-cm, soft, gelatinous, reddish-yellow nodule. The main tumor was a well-to-moderately differentiated leiomyosarcoma, whereas the gelatinous nodule was rhabdomyosarcomatous and contained rhabdomyoblasts that exhibited cytoplasmic cross striations and immunoreactivity for myoglobin. No epithelial elements were detected in the neoplasm. At the time of last follow-up, the patient was undergoing chemotherapy. This is only the second well-documented case of a hybrid leiomyosarcoma-rhabdomyosarcoma of the uterus.

Aged↗
PubMed2003

Malignant peripheral nerve sheath tumor of small round cell type with pleomorphic spindle cell sarcomatous areas.

An unusual case of malignant peripheral nerve sheath tumor (MPNST) arising in the posterior mediastinum of a 59-year-old man is reported. Histopathologically, the tumor showed an admixture of a dense proliferation of small round cells resembling a primitive neuroectodermal tumor (PNET) and a pleomorphic spindle cell sarcomatous area. Abortive rosettes, primitive neural tube-like structures, and a few glandular structures were found in the small round cell area. Small round cells were immunoreactive for neural cell adhesion molecule and synaptophysin, but were not immunoreactive for MIC2 and neuron-specific enolase. Pleomorphic spindle cells were occasionally arranged in a storiform pattern and were diffusely immunoreactive for S-100 protein. The MPNST of small round cell type is distinguishable from PNET by its negative immunoreactivity for MIC2, and the present tumor is assumed to be derived from primitive neuroectodermal cells in the peripheral nerve capable of bidirectional (neuron and Schwann cell) differentiation.

Biomarkers, Tumor↗
PubMed2003

Proliferative funiculitis with a prominent infiltration of mast cells.

A surgical case of proliferative funiculitis (pseudosarcomatous myofibroblastic proliferation of the spermatic cord) with a prominent mast cell infiltration is reported. A 67-year-old man with a history of right inguinal herniorrhaphy 7 years earlier was operated on for diffuse swelling of the inguinal region and scrotum. A large lipoma was found in the inguinal region, and a nodular lesion, measuring 2.7 cm in maximal dimension, was firmly attached to the right spermatic cord. The nodular lesion showed diffuse proliferation of fibroblasts and myofibroblasts associated with the deposition of collagen. A diffuse infiltration of numerous mast cells was found throughout the lesion. Lesions that belong to the group of inflammatory pseudotumors are rarely accompanied by a prominent mast cell infiltration, and the differentiation from mast cell neoplasms is often problematic in such cases. The present case is the first example of proliferative funiculitis associated with this rare phenomenon.

Aged↗
PubMed2003

Blue nevus of the endometrium.

A 36-year-old woman with a long history of amenorrhea underwent endometrial curettage. An aggregate of short spindle cells containing a finely granular, dark brown pigment with the histochemical characteristics of melanin was detected in the endometrial stroma. This finding is considered analogous to the occurrence of similar cells in the endocervical stroma and is most appropriately designated a "blue nevus" of the endometrium. The occurrence of nonneoplastic, melanin-laden cells in the endometrial stroma is an extremely rare phenomenon, which has been reported only once previously.

Adult↗
PubMed2003

Herpes simplex pancreatitis.

Lesions of the pancreas induced by viral infection have drawn relatively little attention because of their low incidence, and the histopathologic features of viral pancreatitis have not been fully elucidated. We report the autopsy findings of 2 patients, a 59-year-old woman with allergic granulomatous angiitis and a 73-year-old man with invasive pulmonary aspergillosis who had a disseminated visceral herpes simplex virus (HSV) infection. In both cases, the liver was the organ most severely affected by the viral infection. The pancreas showed multiple small foci of hemorrhagic necrosis, which were not accompanied by fat necrosis of the surrounding adipose tissue. Histopathologically, Cowdry type A intranuclear inclusions and a ground-glass appearance of the nuclei were found in many degenerated acinar cells around the necrotic foci. The gross appearance and histopathologic features of HSV pancreatitis were characteristic and, in particular, distinct from those of the more common acute hemorrhagic pancreatitis. Immunohistochemistry using an anti-HSV antibody revealed immunoreactivity in the intranuclear inclusions and ground-glass nuclei, and polymerase chain reaction analysis disclosed that the causative virus in these 2 cases was HSV-1. Herpes simplex virus pancreatitis constitutes a rare, but distinct pathologic entity among a group of acute pancreatitis diseases with diverse etiopathogenesis.

Aged↗