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1.
目的探讨儿童髓母细胞瘤显微手术及术后并发症问题。方法回顾性分析经小脑蚓部切开联合四脑室正中孔入路显微手术切除儿童髓母细胞瘤及术后并发症53例。全部经病理证实。结果全部病例术前均行MRI检查,46例同时行CT检查。手术全切除47例(88.7%)、次全切除6例(11.3%)。术后51例高颅压症状消失,临床体征改善,2例死亡。术后发生咸默症5例,其中合并下颏关节脱位1例。术后昏迷2例,呼吸机辅助人工呼吸2周1例,遗留一侧肢体轻瘫2例。中枢性面瘫2例。肿瘤位于小脑蚓部12例,四脑室内18例。小脑蚓部和四脑室内者23例。肿瘤血供来源于小脑后下动脉37例。全部病例均打通中脑导水管。术后37例患者随访6个月至5年3个月。35例接受放疗。其中30例未见复发和转移。4例原位复发,2例脊髓播种性转移。结论儿童髓母细胞瘤由于其临床特点诊断多无困难,但个性化深入了解肿瘤病理解剖及其与周围组织比邻有利于最大限度切除肿瘤。采用显微手术全切除肿瘤组织、解除导水管梗阻、妥善保护小脑后下动脉及其分支、避免伤及脑干及四脑室底是手术操作的关键。病程进展迅速,肿瘤巨大者术后生存质量及生存期更差,早期就诊尤为重要。  相似文献   
2.
Adult medulloblastoma: review of 13 cases with emphasis on MRI   总被引:8,自引:1,他引:7  
Medulloblastomas are generally associated with childhood, but 14–30% occur in adults, accounting for 1% of adult central nervous system tumors. While approximately one third of adult medulloblastomas present as vermian tumors similar to those seen in childhood, the majority differ substantially from the childhood variety. In this series of 13 patients, 5 had lateral, seemingly extra-axial masses in the cerebellopontine angle or at the tentorium, simulating meningiomas or acoustic neuromas, but angiographic hypovascularity in 2 of the latter suggested a diagnosis other than meningioma. Of 4 paramedian tumors, 3 diffusely infiltrated the cerebellar white matter, showed little or no gadolinium enhancement and were not associated with hydrocephalus. Hydrocephalus was present in less than half of our patients; in childhood the reported incidence is 85–100%. A possible association with pregancy was noted.  相似文献   
3.
Summary Thirty adult patients presenting with medulloblastoma between 1974 and 1991 were studied and treated at Puerta de Hierro Clinic. After diagnosis, all patients were treated by surgery followed by radiotherapy and eight of them received adjuvant chemotherapy. We have studied the influence of some factors such as age, sex, location of tumour in the cerebellum, amount of surgical resection and histological variants on survival and recurrence of the disease. Only the histological type has a statistically significant influence on survival and recurrence: we have found that patients presenting classic medulloblastoma have a long survival and a long relapse-free interval.  相似文献   
4.
Summary The ganglioside patterns of medulloblastomas have never been established; in this study we report the ganglioside profile of the human medulloblastoma cell line TE-671 grown as a xenograft in nude mice. Gangliosides were isolated and structurally analyzed by fast atom bombardment mass spectometry following permethylation. Identification of individual gangliosides was also performed by immunostaining of high-performance thin-layer chromatography-separated bands. Total ganglioside levels of 0.20 mol/g of tissue were obtained, consistent with those reported for human glioma cell lines grown as xenografts; predominant monosialogangliosides of TE-671 xenografts were II3--NeuAc-LacCer (GM3) and II3--NeuAc-GgOse3 Cer (GM2) but there were also relatively large proportions of IV3--NeuAc-LcOse4Cer (3-isoLM1), IV3--NeuAc-nLcOse4Cer (3-LM1) and a further ganglioside of the neolactoseries with an extra lactosamine moiety. The only oligosialoganglioside detected was IV3, II3--NeuAc2-GgOse4Cer (GD1a).Abbreviations: The gangliosides have been designated according to Svenerholm [18] GM3 II3--NeuAc-LacCer - GM2 II3--NeuAc-GgOse3Cer - GM1 II3--NeuAc-GgOse4Cer - 3-LM1 IV3--NeuAc-nLcOse4Cer - 3-isoLMI IV3--NeuAc-LcOse4Cer - Fuc-3-isoLMI IV3--NeuAc, III4-Fuc-LcOse4Cer - GD1a IV3, II3--NeuAc2-GgOse4Cer - FAB-MS Fast atom bombardment-mass spectometry - GC-MS gas chromatography-mass spectometry Supported by NC1 RO1 CA11898 to Dr. Bigner and B8803X-00627-24B from the Swedish Medical Research Council to Dr. L. Svennerholm  相似文献   
5.
Medulloblastoma in children and in adults: a comparative study   总被引:1,自引:0,他引:1  
Summary We report on the clinical and pathological characters and factors influencing prognosis in a consecutive series of 20 cases of medulloblastoma presenting in childhood and of 20 cases of the tumour presenting in adulthood. The significant differences which emerged were compared with the findings of the largest published series. Medulloblastoma is more often lateral in site and desmoplastic in histology in adults than in children. On our evidence the age at tumour onset not affect survival.  相似文献   
6.
Summary A review of cranial CT studies of 233 patients for the Second Medulloblastoma Trial of the International Society of Paediatric Oncology showed typical CT appearances in only 30% of patients. The varied appearances encountered are described with particular emphasis on atypical CT features.A shorter version of this paper was published in the Proceedings of the XIV Symposium Neuroradiologicum (Neuroradiology (1991) 33 [Suppl]: 516–517)  相似文献   
7.
 目的 回顾分析髓母细胞瘤的临床特点 ,探讨合理治疗方案及影响预后的因素。方法  1979年 12~ 1998年 12月 ,本科收治髓母细胞瘤 5 4例 ,男 35例 ,女 19例 ,年龄 2 .5~ 2 3.0岁 ,中位年龄 9岁。全部病例先经手术切除 ,(2 5例肉眼全切除 ,2 9例次全切除或部分切除 ) ,病理证实为髓母细胞瘤。术后均接受全脑、全脊髓放射治疗。 32例后颅窝剂量≥ 5 0Gy。 2 2例后颅窝剂量 <5 0Gy。 结果 全部病例 1、3、5和 10年生存率分别为 86 .9%、5 8.8%、5 5 .5 %和 4 8.3%。其中 12例放疗后复发 ,1例放疗后远处转移 (经病理证实 )。多因素分析显示照射剂量 (<) 4 5Gy分组时手术切除程度 (即有无残留 )以及肿瘤部位均对预后有影响(P值分别为 0 .0 2 5和 0 .0 4 9)。剂量 (≤ ) 5 0Gy分组时仅手术切除程度对预后有影响 (P =0 .0 4 3) ,但P值趋大。结论 髓母细胞瘤首选手术 ,术后全脑、全脊髓放射治疗的方法是神经外科及放射治疗医师共同推荐的治疗方案 ,对肿瘤未能完整切除者 ,可通过增加局部放射治...  相似文献   
8.
Medulloblastoma, one of the most common central nervous system(CNS)tumors in children, requires aggressive multimodality therapy including surgery, radiation therapy, and occasionally chemotherapy. Given its intensive treatment regimen and improved survival during the past 20 years, it is likely that a cohort of survivors will result who may incur consequences of therapy, including a second cancer. We used population-based data from the United States and Sweden to estimate risks of second neo plasms in patients with histologically confirmed medulloblastoma (n = 1,262).Overall, there was a 5.4-fold excess of second neoplasms (95 percent confidence interval = 3.3-8.4) based on 20 observed and 3.7 expected cancers. The second cancers occurred eight to 432 months after initial diagnosis(median, 73 months) with significantly elevated ratios for all intervals examined except for less than one year after initial diagnosis. Significantly elevated risks were seen for cancers of the salivary glands, cervix uteri, brain and CNS, thyroid gland, and acute lymphoblastic leukemia. Of the 15second cancers with treatment data, seven occurred in the radiation field or within areas of scatter while two others may have been radiation-related. Although based on small numbers of second cancers, the results suggest that as survival increases, some patients with medulloblastoma will have an increased risk of a second cancer, particularly a radiation-related cancer. Thus, as survival improves, late-occurring consequences of diagnosis and treatment will need to be carefully assessed. Identification of patients hypersensitive to radiation therapy, such as those with Gorlin Syndrome, should also be attempted in order to reduce the sequelae from intensive radiation exposure. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
9.
Prominent neuronal differentiation and MYCN amplification occur only in a small percentage of medulloblastomas (primitive neuroectodermal tumor of the cerebellum). In this article, we describe two medulloblastomas that showed a striking degree of neuronal differentiation with islands of mature neurons associated with abundant neuropil. In these differentiated foci, there were no mitoses or atypia, and the histology was reminiscent of a malformative or hamartomatous lesion. Both tumors were assessed for MYCN amplification by the novel technique of differential polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH). In case 1, MYCN amplification was in the 10 - fold range determined by differential PCR, while in case 2 the level of amplification was marked, with 20 - 30 copies compared with diploid controls. FISH analysis also confirmed the presence of MYCN amplification in both tumors. These two cases are of great interest, especially as they show MYCN amplification in medulloblastomas with marked degree of neuronal differentiation. Furthermore, in both cases, there was evidence of a slower and more indolent clinical course, suggesting a more favorable outcome in medulloblastoma with this degree of neuronal differentiation.  相似文献   
10.
We describe a rare case of medulloblastoma in an adult woman with histological findings suggesting an origin for this neoplasm in the external granular layer or its remnants. The patient presented with cerebellar dysfunction, and neuroimaging revealed a right cerebellar mass lesion. Pathological examination of the operative specimen revealed a medulloblastoma with occasional areas of neuronal or glial differentiation. Zic protein was also detected immunohistochemically in the tumor cells. The tumor cells were mainly distributed in the subarachnoid space and extended to the cerebellar parenchyma through the perivascular space to form tumor nodules. A suggestive finding, as concerns the origin of this neoplasm, was that the tumor cells were also spread evenly along the subpial zone of the molecular layer, reminiscent of the cellular architecture of the fetal external granular layer.  相似文献   
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