Biomedical subjects
T Kayama
Publications and source records attributed to T Kayama.
[A case of olfactory neuroblastoma with intracranial extension and distant metastasis].
Olfactory neuroblastoma is a rare tumor originating in the upper nasal cavity. It rarely extends intracranially. We report a clinical case of olfactory neuroblastoma with intracranial extension and distant metastasis. A 35-year-old man complained of nasal stuffiness and bleeding, headache and vomiting. Neurological examination showed anosmia and papilledema. MRI showed a huge mass that occupied the right nasal and paranasal cavities, and extended into the right frontal base. The tumor was removed totally and was histologically diagnosed as olfactory neuroblastoma. About two months after surgery, however, MRI demonstrated a rapid recurrence of the tumor in the nasal and paranasal cavities and the frontal lobe. Metastatic lesions were also seen in the right cervical lymph nodes. Chemotherapy was administered using cisplatin and etoposide. The tumor in the frontal lobe shrunk markedly but the other lesion persisted. Whole brain irradiation and local irradiation of the cervical lymph nodes were performed. The tumors became smaller but did not disappear. MRI demonstrated spinal dissemination. Irradiation of the whole spinal cord was performed. The metastatic lesions disappeared. The patient was discharged without neurological deficits, but died of pneumonia 15 months after surgery. Olfactory neuroblastoma is a slow-growing tumor and is highly radiosensitive, but it rarely extends or develops multiple distant metastases and seldom shows a short survival time, as in our case. A review of the literature documented responses in patients treated with a cisplatin-based drug combination. We recommend systemic control using cisplatin-based chemotherapy in addition to irradiation to prevent local recurrence in cases of advanced or metastatic olfactory neuroblastoma.
[A case of giant skull myofibroma occupying left anterior cranial fossa].
We report a rare case of giant skull myofibroma occupying left anterior cranial fossa. A 53-year-old woman presented with left exophthalmos for 2 years. Neurological examination showed left exophthalmos, disturbance of bilateral visual acuity, and bitemporal hemianopsia. A CT scan revealed an ossifing mass at left anterior cranial fossa. On magnetic resonance images, the tumor showed iso-intensity on T 1-weighted image, heterogeneous high intensity on T 2-weighted image, and was heterogeneously well-enhanced after administration of Gd-DTPA. The tumor was fed mainly by middle meningeal artery. The patient underwent surgery and the tumor was removed totally. Histological diagnosis of the tumor was myofibroma. The patient has been followed every other month by MRI without any adjuvant therapy. There has been no tumor recurrence for 19 months. There is no other myofibroma in her body, therefore the patient was diagnosed as solitary myofibroma of the skull. Our case is the first report of solitary myofibroma of the skull because we could not find any reports on solitary myofibroma of the skull in the past literature.
Detection of DNA abnormalities by arbitrarily primed PCR fingerprinting: amplification of the MDM2 gene in a mediastinum fibrosarcoma.
Arbitrarily primed PCR (AP-PCR) fingerprinting method is easy and useful for analysis of genetic alterations in anonymous chromosomal regions. We applied this technology to analysis of DNA from human primary cancers and found amplification of a DNA fragment in a mediastinum fibrosarcoma. PCR-based analysis of radiation hybrid panels following cloning and nucleotide sequence determination of the fragment revealed that it was derived from a region of chromosome 12q13-q15. In this region, the MDM2 and IFNG genes were noted as known genes that could be involved in human carcinogenesis. Southern blot analysis of genomic DNA of the tumor revealed the amplification of the MDM2 gene together with the fragment locus, but not the IFNG gene. Our results demonstrated that detection of DNA alterations by AP-PCR fingerprinting without any previous knowledge of the genes and subsequent analysis of radiation hybrid panels could lead to easy identification of candidates for genes involved in carcinogenesis.
Differential regulation of intracellular Ca2+ signalling induced by high K+ and endothelin-1 in single smooth muscle cells of intact canine basilar artery: detection by means of confocal laser microscopy.
Changes in intracellular calcium concentration ([Ca2+]i) in smooth muscle cells play the key role in regulation of vascular smooth muscle tone and pathogenesis of cerebral vasospasm. In this study, we adopted the confocal laser microscopy to detect the fluorescence signals arising from the individual smooth muscle cells of canine basilar artery. Ring preparations were made, loaded with fluo-3 and changes in fluorescence induced by high K+ and endothelin-1 (ET-1) were measured by confocal laser microscopy. In some unstimulated smooth muscle cells Ca2+ waves arising from discrete region of the cell propagated to the whole cell with a velocity of approximately 10 microm/s. High K+ (80 mmol/L) induced a rapid rise in [Ca2+]i, the peak level being consistently reached approximately 10 s after stimulation. In contrast, the time to peak level of [Ca2+]i induced by ET-1 (0.3 micromol/L) varied widely between 13 and 26 s among individual cells, an indication that the extent of nonuniform coordination of increases in [Ca2+]i in individual cells may be partly responsible for the different time courses of tension development of vascular smooth muscle in response to the vasoactive stimulants. The increase in [Ca2+]i induced by ET-1 was transient but a pronounced and sustained contraction developed further in response to ET-1. Thus ET-1 has a biological property as a potential candidate to elicit cerebral vasospasm. Confocal laser microscopy could be a useful tool to measure the changes in [Ca2+]i in individual smooth muscle cells of cerebral artery.
Structures of primer-template hybrids in arbitrarily primed polymerase chain reaction.
Nucleotide sequence analysis of arbitrarily primed PCR products from two known regions of human genome revealed that at least six contiguous bases at the 3'-end of a primer of 20 bases, were perfectly matched in the primer-template hybrids.
Clinical and neuroradiological features of intracranial vertebrobasilar artery dissection.
BACKGROUND AND PURPOSE: We sought to determine the clinical and neuroradiological features of intracranial vertebrobasilar artery dissection. METHODS: The clinical features and MR findings of 31 patients (20 men and 11 women) with intracranial vertebrobasilar artery dissections confirmed by vertebral angiography were analyzed retrospectively. The vertebral angiography revealed the double lumen sign in 11 patients (13 arteries) and the pearl and string sign in 20 patients (28 arteries). RESULTS: The patients ranged in age from 25 to 82 years (mean, 54.8 years). Clinical symptoms due to ischemic cerebellar and/or brain stem lesions were common, but in 3 cases the dissections were discovered incidentally while an unrelated disorder was investigated. Headache, which has been emphasized as the only specific clinical sign of vertebrobasilar artery dissection, was found in 55% of the patients. Intramural hematoma on T1-weighted images has been emphasized as a specific MR finding. The positive rate of intramural hematoma was 32%. Double lumen on 3-dimensional (3-D) spoiled gradient-recalled acquisition (SPGR) images after the injection of contrast medium was identified in 87% of the patients. The 3-D SPGR imaging method is considered useful for the screening of vertebrobasilar artery dissection. CONCLUSIONS: Intracranial vertebrobasilar artery dissection is probably much more frequent than previously considered. Such patients may present no or only minor symptoms. Neuroradiological screening for posterior circulation requires MR examinations, including contrast-enhanced 3-D SPGR. Angiography may be necessary for the definite diagnosis of intracranial vertebrobasilar artery dissection because the sensitivity of the finding of intramural hematoma is not satisfactory.
Removal of petrous apex meningioma and microvascular decompression for trigeminal neuralgia through the anterior petrosal approach. Case report.
A 64-year-old female presented with right trigeminal neuralgia. Computed tomography and magnetic resonance (MR) imaging demonstrated a tumor attached to the right petrous apex. MR imaging also revealed that the trigeminal nerve was compressed and distorted by the tumor. Tumor removal and microvascular decompression (MVD) were performed via the anterior petrosal approach. The trigeminal nerve was distorted by the tumor and the superior cerebellar artery compressed the medial part of the root entry zone of the trigeminal nerve. The surgery resulted in complete relief of the trigeminal neuralgia. Posterior fossa tumors causing ipsilateral trigeminal neuralgia are not rare, and are often removed via the suboccipital retromastoid approach, as MVD for trigeminal neuralgia is usually performed through the retromastoid approach. The advantages of the anterior petrosal approach are shorter access to the lesion and direct exposure without interference from the cranial nerves, and that bleeding from the tumors is easily controlled as the feeding arteries can be managed in the early stage of the surgery. We conclude that the anterior petrosal approach is safe and advantageous for the removal of petrous apex tumor associated with trigeminal neuralgia.
[A case of TSH-secreting pituitary adenoma associated with an unruptured aneurysm: successful treatment by two-stage operation and gamma-knife].
We report a successfully treated case of invasive TSH-secreting pituitary adenoma associated with an unruptured internal carotid artery aneurysm by two-stage operation and gamma-knife radiosurgery. A 64-year-old woman was admitted to our department with a 3-year history of general fatigue and 1-year history of anxiety, palpitation and hyperhydrosis. Endocrinological examination revealed hyperthyroidism with elevated TSH, GH and somatomedin C. Magnetic resonance images demonstrated a tumor in the sella turcica which extended into the left cavernous sinus, furthermore, indicated aneurysm-like flow void at the ventral part of the left internal carotid artery. The aneurysm was confirmed by conventional angiography. Neck clipping of the aneurysm was performed through pterional approach as the first operation. One month later, at the second operation, the pituitary adenoma except for cavernous sinus portion was resected via the transsphenoidal approach. Immunohistological examination revealed positive for TSH and GH. Gamma-knife radiosurgery with a central dose of 33.3 Gy and peripheral dose of 17 Gy was carried out for residual tumor at the cavernous sinus under both MRI and CT guidance. Posttreatment course was uneventful with normalization of thyroid function at 16 months after gamma-knife. Two-stage operation and gamma-knife radiosurgery is effective for TSH-secreting adenoma extending into the cavernous sinus associated with an unruptured aneurysm.
[New ideas for indirect revascularization surgery for moyamoya disease].
We had performed indirect revascularization surgery, mainly EMS, for cases with moyamoya disease, because EMS can revascularize a large area including the territory of anterior cerebral artery. However, in our initial cases, we found that three sides in two cases had post-operative ischemic complications. These cases suggested that intracranial hypertension due to pressure exerted by swelling caused by edema in the myoflap after EMS was one of the reasons for these infarctions. For the prevention of intracranial hypertension due to the edema in the myoflap, when we did EDAMS with dural pedicle insertion, we put into practice the new ideas about shaving the boneflaps to half of their original thickness, and prescribed 20% Mannitol after surgery. We tried these new ideas concerning treatment on four sides in three cases with moyamoya disease, and we were able to get good outcomes without any new neurological deficits.
Distant metastasis of liposarcoma to the dura and skull: a case report.
A case of metastatic liposarcoma of both skull and brain originating from the lower extremity is described. A 44-year-old male underwent removal of a myxoid type liposarcoma in his left upper thigh and a second operation for local recurrence. A metastatic liposarcoma was also discovered in the mediastinum and treated by radiotherapy. Six years after the initial onset, he presented with progressive consciousness disturbance, motor aphasia, right hemiparesis and subcutaneous swelling in the left frontal region. Neuroimaging showed a large tumour extending both intracranially and extracranially across the eroded skull. The intracranial portion of the tumour had invaded the frontal lobe. The tumour was subtotally removed. The operative findings suggested that the tumour had metastasized to the dura mater or the skull initially, and invaded the surrounding tissues. The histological appearance was the same as those of the previous tumours.
Detection of DNA abnormalities by arbitrarily primed PCR fingerprinting: allelic losses in chromosome 10q in lung cancers.
DNA fingerprinting using arbitrarily primed PCR (AP-PCR) is useful for detecting cancer-specific DNA aberrations without targeting any particular genes or knowing any nucleotide sequences in advance. AP-PCR fingerprinting is an efficient method for finding loss of anonymous chromosomal regions in cancers. We analyzed DNA from 44 human non-small cell lung cancers by fingerprinting using a single primer and found a loss of signal intensity in a DNA fragment amplified from chromosome 10 (fragment F) in 15 tumors. The detailed location of the fragment F locus on chromosome 10q was determined by PCR-based analysis of radiation hybrid panels using a sequence-tagged site established for the fragment. In 12 of the 15 tumors, loss of the signal detected by AP-PCR fingerprinting was in agreement with the results obtained by analysis of allelic imbalances using 7 polymorphic CA-microsatellite DNA markers for loci around the fragment F locus (p=0.0009). We conclude that a hitherto unknown suppressor gene for lung cancer resides at 10q in the vicinity of fragment F.
Combined chemotherapy and radiation therapy for central nervous system germ cell tumors: preliminary results of a Phase II study of the Japanese Pediatric Brain Tumor Study Group.
The authors conducted a multiinstitutional phase II study to establish a postsurgical combined chemotherapy and radiation therapy regimen for patients with primary germ cell tumors of the brain. After surgical debulking of the tumor and histological verification, patients were divided into three therapeutic groups: good prognosis, intermediate prognosis, and poor prognosis. Patients received two kinds of chemotherapy (three courses) prior to receiving radiation therapy: carboplatin-etoposide combination ([CARB-VP]: carboplatin 450 mg/m(2) on Day 1, etoposide 150 mg/m(2) on Days 1-3) or ifosphamide-cisplatin-etoposide combination ([ICE]: ifosphamide 900 mg/m(2), cisplatin 20 mg/m(2), and etoposide 60 mg/m(2) on Days 1-5). Patients in the good prognosis group (those with germinomas) were treated with CARB-VP followed by local radiation therapy (24 Gy). Patients in the intermediate prognosis group received CARB-VP followed by local radiation therapy (50 Gy); they received five additional chemotherapy treatments. Patients in the poor prognosis group received ICE followed by whole craniospinal radiation therapy; they also received five additional chemotherapy treatments. Eighty-two patients were evaluated. For the 56 patients with germinomas, a 93% rate of complete remission after treatment was achieved. The remission rate was 76% for 21 patients in the intermediate prognosis group, and no recurrence was detected during a median follow-up period of 2.6 years. In the group of five patients with poor prognosis, the disease in three patients progressed during chemotherapy or radiation therapy and they died within 6 months. There were no serious complications in the surviving patients. The authors found their treatment protocols to be currently effective for patients with germinomas and those with an intermediate prognosis.
Three-dimensional and ultrastructural ICAM-1 distribution in the choroid plexus, arachnoid membrane and dural sinus of inflammatory rats induced by LPS injection in the lateral ventricles.
To investigate immunological environment in the cerebrospinal fluid (CSF) system, ultrastructural and three-dimensional localization of intercellular adhesion molecule-1 (ICAM-1) was studied in the choroid plexus, arachnoid membrane and dural sinus of LPS-stimulated rats with immuno-SEM and TEM. The choroid plexus epithelial cells expressed rich ICAM-1 along the microvilli. The arachnoid trabeculae fibroblast-like cells demonstrated ICAM-1 expression on both sides facing the subarachnoid space moderately. The dural sinus endothelial cells, however, showed only few ICAM-1 expression and no specific localization. These results suggest that the choroid plexus and arachnoid membrane may play an important mutual role for leukocyte migration in the CSF system, and that the CSF system may function in immunoreaction independently of the vascular system with the aid of up-regulated ICAM-1 expression.
Production and secretion of endothelin-1 by cultured choroid plexus carcinoma cells.
Choroid plexus carcinoma is a rare neoplasm derived from the epithelium of the choroid plexus. The production and secretion of endothelin-1 (ET-1) by cultured human choroid plexus carcinoma cells were studied by radioimmunoassay and Northern blot analysis. Immunoreactive (IR)-ET was detected in the culture medium (2.78 +/- 0.12 fmol/10(5) cells/24 h; n = 5; mean +/- SEM) but not in the unconditioned medium. Reverse-phase high-performance liquid chromatography of the extract of the culture medium showed a single peak eluting in the position of ET-1. Treatment with tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) or a combination of interferon-gamma (IFN-gamma), TNF-alpha, and IL-1 beta caused significant increases in the IR-ET levels in the culture medium. Northern blot analysis of total RNA showed the expression of ET-1 mRNA in choroid plexus carcinoma cells. The expression levels of ET-1 mRNA were increased by treatment with a combination of IFN-gamma, TNF-alpha, and IL-1 beta. The present study has shown the production and secretion of ET-1 by cultured human choroid plexus carcinoma cells and suggests the possibility that ET-1 formation is related to the pathophysiology of this tumor.
[Contemporary treatment against petroclival meningioma].
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[Transsphenoidal surgery and gamma-knife radiosurgery for a treatment of recurrent craniopharyngioma with moyamoya vessels].
A recurrent craniopharyngioma associated with moyamoya vessels was successfully treated by partial removal of the tumor via the transsphenoidal approach followed by gamma-knife radiosurgery. This 19-year-old man was first treated by partial tumor removal and radiotherapy (54Gy) at the age of 6 years. Growth hormone and human chorionic gonadotropin were given from the ages of 13 to 18 years. At ag 17 years, follow-up magnetic resonance imaging (MRI) revealed regrowth of the tumor. At the age of 19 years, he was readmitted for treatment of the enlarging remnant tumor. Neurological examination revealed bilateral blindness. MRI showed marked suprasellar, sphenoidal and bilateral cavernous sinus extension of the tumor. Angiography revealed stenosis of the right internal carotid artery and the M1 and A1 segments of the right cerebral arteries, as well as occlusion of the C3 segment of the left internal carotid artery. There were vault and ethmoidal moyamoya vessels. The patient underwent tumor removal via the transsphenoidal approach, instead of craniotomy, to avoid injury to the transdural anastomosis. The intrasellar solid tumor was partially removed. The tumor was then irradiated by the gamma knife. MRI 15 months after the treatment showed marked reduction of the tumor. The pathogenesis of the moyamoya phenomenon and the choice of the treatment in this patient are discussed.
Edema along the optic tract: a useful MR finding for the diagnosis of craniopharyngiomas.
BACKGROUND AND PURPOSE: The pattern of edema caused by craniopharyngiomas and other common suprasellar masses could be useful for determining the differential diagnosis of lesions in this region. The purpose of this study was to ascertain whether the pattern of edema spread on MR images can be used in the diagnosis of craniopharyngiomas. METHODS: The preoperative MR images in eight consecutive patients with craniopharyngiomas, 15 patients with large pituitary adenomas compressing the optic chiasm, and six patients with tuberculum sellae meningiomas were evaluated. All the patients were treated surgically at our hospital and a pathologic diagnosis was obtained. We analyzed the spread of edema surrounding the tumor on the coronal dual-echo fast spin-echo images and compared this finding with tumor location and size as seen on contrast-enhanced T1-weighted images. RESULTS: Not only peritumoral edema but also edema spreading along the optic tracts was observed in five patients with craniopharyngiomas, one of whom also had edema within one optic nerve. The location of edema in the visual pathway was not always associated with the degree of visual disturbance. None of the patients with large pituitary adenomas or with tuberculum sellae meningiomas had such edema along the visual pathway. CONCLUSION: Edema caused by craniopharyngiomas tends to spread along the optic tracts. It is a useful MR finding for distinguishing craniopharyngiomas from other common parasellar tumors.