We report a case of congenital ependymoblastoma. A female fetus was prenatally diagnosed as having a posterior fossa tumor and hydrocephalus on prenatal ultrasound study. She was born at 39 weeks of gestation with birth weight of 2846g. The head circumference was enlarged to 39.4cm. A miniature Ommaya's reservoir was inserted to control hydrocephalus on day 4 of life. Tumor biopsy was performed on day 11 and followed by chemotherapy. The histologic specimen showed dense cellularity with abundant ependymoblastemal rosettes and mitotic figures. Histopathological diagnosis of ependymoblastoma was made. On immunohistochemical studies, the rosettes showed strong positivity for vimentin. GFAP was positive in several rosettes. EMA was positive on the luminal surface of some rosettes. There was a small area in which cells were relatively sparse and this area showed neurofilament and synaptophysin positivity, which is unusual for ependymoblastoma.
Ependymoblastoma is classified as an embryonal tumor in the WHO classification of brain tumor 2000. It is presumed that ependymoblastoma arises from a primitive neuoroepithelial cell showing some phenotypic features of ependymoglia. Neural components are usually not seen in ependymoblastoma. Ependymoblastoma with neural differentiation has been reported previously as a rare entity. Although the abundance of ependymoblastemal rosettes could easily lead to a dignosis of ependymoblastoma, it seemed important to note the neural component when considering further characteristics and classification of this highly primitive tumor.

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A hypointense core with a hyperintense rim is the most common signal characteristic on T2-weighted MRI in intracranial tuberculomas. We examined and contrasted the extracted sections of intracerebral tuberculoma with MRI findings. Central hypointensity of lesions was related to necrosis. T2-high ring was related to CD 68-positive macrophages and Langerhans giant cells. Interestingly small macrophages showed MIB-1-positive at most up to 10%. Among those inflammatory cells, spindle-shaped fibroblasts were mixed. There were no brain tissue in the nodule but gliotic brain tissue existed outside it.

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MIB-1 immunohistochemistry is a useful adjunct in neuropathological diagnosis. Higher MIB-1 staining indices generally correlate with increased risk of recurrence and rapid growth. However, the methodology of immunostaining and counting, and the special cut-off levels have varied considerably among studies. The author reviewed the literature to find the validity and the limitation of MIB-1 immunohistochemistry in brain tumors.

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Erdheim-Chester disease is a rare systemic histiocytic disorder. The authors present a case of a 65-year-old woman suffering from chronic pericardial effusion of undetermined etiology for several years. She was referred to us with weakness of the right extremities and speech disturbance. Neuroradiological studies showed multiple dura- based lesions. Huge right extra-cerebral lesion was removed and histopathological examination revealed a histiocytic proliferation positive for CD68 and negative for S100 with scattered Touton type giant cells, consistent with Erdheim-Chester disease. Plain X-ray showed pathognomonic sclerotic change of the meta/diaphyses of the femur and tibia. Erdheim-Chester disease should be considered in a differential diagnosis of dura-based lesions.

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Brain tumors amount to less than 2% of all malignant neoplasms; however, they are the most common solid tumors in children, causing nearly one quarter of all childhood cancer death, and the incidence of pediatric brain tumors seems to increase more rapidly than any other tumor type. The majority of adult glioblastomas (WHO grade IV) occur in older patients after a short clinical history without clinical or histopathological evidence of a less malignant precursor lesion (primary or de novo glioblastoma). Another type of glioblastoma, so-called secondary glioblastoma, progressively develops in younger patients more slowly from low-grade diffuse (WHO grade II) or anaplastic astrocytoma (WHO grade III). Distinct genetic pathways have been reported, related to tumor progression in adult astrocytic tumors. Pediatric glioblastomas resemble secondary glioblastomas in that the patients are young, but the tumors are mostly primary. Compared with the extensive efforts that has been directed at characterizing the molecular features of adult astrocytoma progression, relatively little data have been reported on pediatric tumors, in part reflecting the fact that these lesions are less common. It has also remained uncertain whether tumor classification into genetic subtypes as defined for adult astrocytomas could be defined for childhood astrocytomas. We reviewed whether the genetic alterations documented for adult astrocytomas are also operative in younger tumors.

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We are using a protocol to have made the chemotherapy by cyclophosphamide (CPA), etoposide (VP16), Cisplatin (CDDP), and vincristine(VCR) to the cases of mixed germ cell tumor. At this protocol, When a remaining neoplasm is recognized at the end of the 4th course of chemotherapy, it will do high dose chemotherapy which taken thiotepa (TESPA) and melphalan (L-PAM) together with peripheral blood stem cell transplantation (PBSCT) for the 5th course. This time, We experienced 2 patients of mixed germ cell tumor, the neoplasm disappeared only by chemo-radiotherapyl in 1 Patient and was able to get good result in doing salvage surgery to the remaining neoplasm in the other patient. When the neoplasm remains after the chemo-radiotherapy, salvage surgery is recommended. In addition, it should consider that it makes adjuvant therapy without histological diagnosis to the case that the tumor marker is raising.

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In 184 cases harboring meningiomas that we performed the surgical resection between 1993 and 1998,36cases were recurrent. In these recurrent cases, we investigated 15 cases that were removed totally (Simpson I or II )with first operation. We classified those 15 cases into three groups on the basis of WHO brain tumor's histological classification of 2000.
Group A was included atypical or anaplastic meningiomas from onset to recurrence. Group B was included the cases changing from benign type to atypical or anaplastic meningiomas. Group C was included the cases showing histologically benign type in the recurrence. About those three groups, we studied MIB-1 LI by immunohistology, DNA index with FCM.
In the group A (histologically, malignant to malignant), MIB-1 LI was initially high value, but recurrently high value. DNA index had the same tendency.
In the group B( histologically, benign to malignant), MIB-1 LI showed initially low value, but recurrentlly into high value. DNA-index has the same tendency except case 4. Only DNA index of case 4 was initiallyl.08slight high and malignant.
In the group C (histologically, benign to benign), MIB-1 LI was initially low, but recurrently medium or high. DNA-index has two tendencies. One is initially low, but recurrently low, and the other is initially low, but recurrently slight high.
DNA-histogram in the group A and B revealed aneuploidy pattern. In the group C, it revealed all diploid pattern.
In the result of that, MIB-1 LI and DNA index were correlated each other.
But in the group B and C, it was hard to predict the malignant change except case 4. For the purpose of the effective prediction, we will need more studies including other predictive factors and accumulation of the cases.
In recurrent meningiomas, there were some cases having high proliferative rate in spite of histologically benign. We concluded not only histological malignancy but also proliferative rate were very important, when we predict it's recurrence.

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