Fukui M

Results of a long-term follow-up after neuroendoscopic biopsy procedure and third ventriculostomy in patients with intracranial germinomas

OBJECTnThe authors report the results of long-term follow-ups in 12 patients with intracranial germinomas who underwent neuroendoscopic procedures before chemotherapy and radiotherapy, and discuss the usefulness and safety of these procedures.nnnMETHODSnBetween January 1996 and December 2005 at Kyushu University Hospital, 12 patients with intracranial germinomas underwent neuroendoscopic biopsy procedures involving a flexible fiberscope. Eight patients simultaneously underwent endoscopic third ventriculostomy (ETV) for existing obstructive hydrocephalus. All patients received chemotherapy and radiotherapy postoperatively, according to the regimen promulgated by the Japanese Pediatric Brain Tumor Study Group. The patients were followed for an average of 78.6 months (range 15-134 months), and a retrospective study was conducted.nnnRESULTSnGerminomas were histologically verified in all patients. No postoperative deaths or permanent morbidity was related to the neuroendoscopic procedures. No other cerebrospinal fluid diversion, such as that achieved with a ventriculoperitoneal shunt, was needed for the management of hydrocephalus. A complete response to postoperative chemotherapy and radiotherapy was achieved in all cases. Only one patient had a recurrent lesion in the spinal cord 6 years after the initial treatment; however, this patient had undergone only the neuroendoscopic biopsy procedure without ETV.nnnCONCLUSIONSnNeuroendoscopic procedures can permit a precise histological diagnosis of intracranial germinomas and are safe and effective in the management of hydrocephalus associated with these tumors. The risk of tumor dissemination due to the neuroendoscopic procedures appears to be minimal when the appropriate chemotherapy and radiotherapy are provided postoperatively.

Effects of l-NMMA and l-NNA on the Selective ATP-Induced Enhancement of Intratumoral Blood Flow

We studied the effects of NG-monomethyl-l-arginine (l-NMMA) and Nω-nitro-l-arginine (l-NNA) on the selective ATP and adenosine-induced enhancement of intratumoral blood flow in rats measured by the hydrogen clearance method. Both adenosine and ATP produced a selective enhancement of the intratumoral blood flow. Neither l-NMMA nor l-NNA had a significant effect on either the CBF or the intratumoral blood flow. Adenosine-induced enhancement was not inhibited by l-NMMA or l-NNA. On the other hand, the ATP-induced enhancement was totally inhibited by both l-NMMA and l-NNA. The inhibitory action of l-NMMA against ATP was blocked by l-arginine, but not by d-arginine. It is suggested that the ATP-induced increase of intratumoral blood flow is evoked by nitric oxide synthesized from the endothelium of the intratumoral blood vessels.

Differential expression of CD44 variants among meningioma subtypes

Aims/background—CD44 is a widely distributed cell surface molecule which has numerous isoforms generated by alternative splicing. The diverse functions related to the CD44 variants (CD44v) have been reported in various physiological and pathological conditions. The pattern of expression of CD44v among meningioma subtypes was investigated to ascertain whether CD44 variants play a role in a variety of biological processes, such as epithelial differentiation and extracranial metastasis. Methods—Twenty three meningiomas were studied immunohistochemically using novel antibodies directed against CD44 isoforms. Six of the 23 samples were analysed by reverse transcription polymerase chain reaction (RT-PCR), followed by Southern blotting with CD44v specific probes. Results—In meningothelial, fibrous and anaplastic meningiomas, a standard form of CD44 was detected by RT-PCR and was homogeneously expressed in tumour cells when studied immunohistochemically. CD44v was not detected in these subtypes. In secretory meningiomas, however, CD44v isoforms were strongly expressed in the cell clusters that produce secretory granules and also accumulated in the granules. The population of tumour cells immunopositive for CD44v was similar to that which stained with antibodies directed against carcinoembryonic antigen, epithelial membrane antigen and ezrin. On RT-PCR with Southern blotting, only the secretory type showed high level expression of CD44v. Conclusions—CD44v in meningiomas is expressed in relation to tumour cell differentiation towards the epithelial type.

Proliferative activity and apoptosis of Langerhans histiocytes in eosinophilic granulomas as evaluated by MIB-1 and TUNEL methods

Aims—To identify the role played by apoptosis in tumour regression. Methods—The growth fraction and apoptotic cell loss of four cases of eosinophilic granuloma were investigated using monoclonal antibodies against Ki-67 proliferation marker (MIB-1) antigen and the TdT mediated dUTP-biotin 3′-OH nick end labelling (TUNEL) method. These data were then compared with the clinical growth rate. Results—Only the Langerhans histiocytic cells, which reacted positively with anti-S-100 protein antibody, were immunolabelled with antibodies to proliferating cell nuclear antigen and Ki-67 antigen (MIB-1). Many apoptotic figures of histiocytic cells were also detected in all cases by the TUNEL method. In a patient whose tumour clinically showed spontaneous regression, the TUNEL staining index gave a higher score than the MIB-1 staining index. Conclusions—The main cause of the spontaneous regression of the tumours was postulated to be programmed cell death (apoptosis).