Keiichi Akatsuka

Mixed germ cell tumors with abundant sarcomatous component in the temporal lobe after radiochemotherapy of neurohypophyseal germinoma: a case report.

We report a case of intracranial germ cell tumor that showed pathological changes from neurohypophyseal germinoma to mixed germ cell tumors consisting exclusively of undifferentiated sarcomatous component after radiochemotherapy. Three surgical specimens and autopsied brain from the patient were histologically examined. An initial specimen from the neurohypophyseal tumor was diagnosed as germinoma with a two-cell pattern. Five years later, after repeated radiochemotherapy, the second specimen resected from the right temporal lobe showed mixed germ cell tumors consisting of the three components of germinoma, choriocarcinoma, and immature teratoma. Six months later after intensive radiotherapy, the right temporal tumor recurred and was surgically removed. The histological diagnosis was mixed germ cell tumors with abundant immature teratoma component. The patient died of uncontrollable tumor growth with repeated intratumoral hemorrhages. The autopsied brain showed sarcoma with angionecrosis. This pathological alteration indicated an increase in the sarcomatous component after undergoing various treatments. We discuss the histological changes of intracranial germ cell tumor modified by treatment.

Role of 12-HPETE in the Pathogenesis of Cerebral Vasospasm

Delayed cerebral vasospasm occurring between the 4th day and the 14th day after subarachnoid hemorrhage (SAH) affects the patient outcome seriously. Its occurrence correlates to the presence and the amount of subarachnoid clot. It is different from ordinary constriction of vessel, since the cerebral vasospasm is delayed onset and long lasting contraction of the vessel which also involves histological changes. Although almost all substances which existed in blood clot had been investigated as candidates caused delayed vasospasm, no substance by itself had been accepted as a cause. Watanabe et al.1 and Shimizu et al.2 reported that 12-hydroxyeicosatetraenoic acid (12-HETE) was detected in subarachnoid clot using the canine SAH model, and 5–1 ipoxygenase pathway of arterial wall with vasospasm was much activated compared with the control vessel. Moreover, 12-hydroperoxyeicosatetraenoic acid (12-HPETE) injected into canine major cistern was produced delayed onset and long lasting vasospasm comparable to the canine SAH model. The injected 12-HPETE into the canine major cistern was decreased rapidly and disappeared from cerebrospinal fluid (CSF) at 6 hours after its injection3. It was interesting and curious that the vasospasm occurred after 12-HPETE disappeared from CSF. The present study was aimed to clarify the trace of injected 12-HPETE into canine major cistern.

Preventive effects of interleukin 1 β for ACNU-induced myelosuppression in malignant brain tumors: the experimental and preliminary clinical studies

SummaryThe effect of recombinant human interleukin 1 β (rHuIL-1 β) on myelosuppression induced by 3-[(4-amino-2-methyl-5-pyrimidynyl)methyl]-1-(2-chloroethyl)-1-nitrosourea hydrochloride (ACNU) was studied. In in vivo study using BALB/c mice, pretreatment with 1 µ g/mouse of rHuIL-1 β as a single intraperitoneal (i.p.) injection had a significant preventive effect on thrombocytopenia as well as granulocytopenia induced by ACNU at an intravenous dose of 60 mg/kg. Facilitated recovery by rHuIL-1 β administered seven days after injection of high-dose ACNU was also observed. Experimental combination immunochemotherapy with high-dose ACNU and rHuIL-1 β was performed in nude mice inoculated with human glioblastoma subcutaneously. The elongation of the survival time of the tumor bearing nude mice was also observed in combined use of high dose ACNU with rHuIL-1 β. Seven patients with malignant brain tumors received intravenous 2.5-3 mg/kg ACNU. All patients were subcutaneously injected with 2 × 104-U or more rHuIL-1 β twice a week or daily. The mean nadir of leukocyte, granulocyte, and thrombocyte counts of the 7 patients received 2.5-3 mg/kg ACNU were significantly higher than in matched historical controls. In combination with rHuIL-1 β, it may be possible to use chemotherapeutic agents at a relatively high dose.

Application of phase sensitive imaging (PSI) for hemorrhage diagnosis in pituitary adenomas

Abstract Objective: Intratumoral hemorrhaging is a common occurrence in pituitary adenomas. Asymptomatic pituitary apoplexies have become more frequently diagnosed due to recent advances in magnetic resonance (MR) imaging. The purpose of this study was to investigate the usefulness of phase sensitive imaging (PSI) in the diagnosis of hemorrhages within pituitary adenomas. Patients and methods: PSI methodology was applied to 28 patients with surgically diagnosed pituitary macroadenomas, and compared with conventional methods. No patients presented with sudden onset of apoplectic symptoms. A 3·0 T MR unit was used to examine all patients before surgery. Results: Seventeen of 28 cases exhibited a hemorrhage component on PSI. However, hemorrhaging was demonstrated in 13 of 28 cases by T2-weighted imaging (T2WI). Hemorrhaging was detected in pituitary adenomas by PSI, but not by T2WI, in four of 17 cases. Poor visualization of the hemorrhage in the sellar turcica was a drawback, which was due to PSI artifacts. Conclusion: We suggest that PSI be used to provide diagnostic assistance for pituitary apoplexies.

A pediatric intramedullary spinal cord tumor with unusual solid-cystic and papillary features: A case report

Spinal cord tumors are rare in children. We report a novel case of pediatric intramedullary spinal cord tumor with unusual solid‐cystic and papillary features. Clinically, the patient presented at the age of 3 years with motor deficit and urinary incontinence, and MRI demonstrated multilocular cystic lesions in the thoracic spine. Histologically the tumor consisted of solid, sheet‐like components and branching papillary structures, and immunohistochemistry demonstrated positive reactivity for epithelial membrane antigen, cytokeratins (7, AE1/3, CAM5.2), E‐cadherin and transthyretin, and negativity for GFAP, S‐100 protein, synaptophysin and neurofilament. These histological and immunohistochemical findings appeared to be unique, and were not compatible with the features of classical ependymoma or choroid plexus papilloma. The clinical behavior, characterized by relatively rapid tumor regrowth after surgical resection and a relatively high MIB‐1 labeling index, suggest that this tumor might have had moderate malignant potential. This pediatric case appears to be particularly informative with regard to the tumor biology or tumorigenesis of intramedullary spinal cord tumor with unusual solid‐cystic and papillary features.

An abrupt fall in blood pressure in aneurysmal subarachnoid hemorrhage

Background We reported previously that some patients with aneurysmal subarachnoid hemorrhage (SAH) demonstrated an abrupt fall in blood pressure (FBP) during the acute period. We further examined this phenomenon in relation to several important clinical variables in a new series using multivariate analysis.