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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Extracranial metastases of a poorly differentiated medulloblastoma in a 12-year-old girl were studied by thin section transmission electron microscopy and immunohistochemistry. The primary tumor did not show any differentiation as revealed by immunohistochemistry. On the contrary, the metastatic tumor cells and their processes disclosed features of neuroblastic differentiation when examined ultrastructurally: microtubules, dense core vesicles, and abortive synaptic ribbons. Several dystrophic neurites containing altered subcellular organelles were also found. Furthermore, few processes contained concentric arrays of paired membranes. This report is the first to clearly show the neuronal differentiation of extracranial metastases of poorly differentiated medulloblastoma. We speculate that metastases of medulloblastomas outside the neuraxis behave analogously to medulloblastoma explants cultured in vivo.
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PMID:Neuroblastic differentiation of metastases of medulloblastoma to extracranial lymph node: an ultrastructural study. 179 29

Medulloblastoma, a highly malignant pediatric tumor of the posterior fossa, demonstrates a marked propensity for leptomeningeal dissemination. Although the predominant site of relapse is the posterior fossa, the prevention of subarachnoid spread would be of significant therapeutic value. The established medulloblastoma cell lines D283 Med, D341 Med, D384 Med, D425 Med, D458 Med and Daoy have been investigated in in vitro adhesion assays for their capacity to bind to the predominant components of the leptomeningeal extracellular matrix: fibronectin, laminin and collagen IV. Growth on the reconstituted basement membrane matrix, Matrigel, was also assayed. Of the five neuronal phenotype DMed lines, all of which grow spontaneously as macrospheroids in standard fetal calf serum-containing tissue culture medium, only D425 Med and its sibline, D458 Med, derived from a subsequent sample from the same patient, displayed adherence to any of the substrata: approximately 20% of input D425 Med cells attached and exhibited cell spread and some extension (adhesion) on fibronectin. All other DMed lines failed to attach to these substrates. The glial phenotype cell line Daoy, which grows as an adherent monolayer under normal culture conditions, exhibited attachment, extension and growth on all substrata as did the glioma cell line U-251 MG and the neuroblastoma cell line SK-N-SH. The lack of attachment, and thus spread on components of the leptomeningeal extracellular matrix under in vitro assay conditions by 5/6 of the medulloblastoma cell lines investigated, is characteristic of neuronally differentiated cells, thus reinforcing the previously described neuronal phenotype of these lines. The readily demonstrated expression of N-CAM and L1 by all of the medulloblastoma cell lines suggests that the primary mode of leptomeningeal extension in vivo may be dependent on such other cell-cell and cell-substrate binding mechanisms.
Invasion Metastasis 1991
PMID:Medulloblastoma cell-substrate interaction in vitro. 182 45

Seventy-seven patients presenting with medulloblastoma between 1958 and 1986 were treated at Stanford University Medical Center and studied retrospectively. Multimodality therapy utilized surgical extirpation followed by megavoltage irradiation. In 15 cases chemotherapy was used as adjunctive treatment. The 10- and 15-year actuarial survival rates were both 41% with an 18-year maximum follow-up period (median 4.75 years). There were no treatment failures after 8 years of tumor-free survival. Gross total removal of tumor was achieved in 22 patients (32%); the surgical mortality rate was 3.9%. No significant difference was noted in the incidence of metastatic disease between shunted and nonshunted patients. The classical form of medulloblastoma was present in 67% of cases while the desmoplastic subtype was found in 16%. Survival rates were best for patients presenting after 1970, for those with desmoplastic tumors, and for patients receiving high-dose irradiation (greater than or equal to 5000 cGy) to the posterior fossa. Although early data on freedom from relapse suggested a possible beneficial effect from chemotherapy, long-term follow-up results showed no advantage from this modality of treatment. The patterns of relapse and survival were examined; 64% of relapses occurred within the central nervous system, and Collins' rule was applicable in 83% of cases beyond the period of risk. Although patients treated for recurrent disease could be palliated, none were long-term survivors. The study data indicate that freedom from relapse beyond 8 years from diagnosis can be considered as a cure in this disease. Long-term follow-up monitoring is essential to determine efficacy of treatment and to assess survival patterns accurately.
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PMID:Medulloblastoma: freedom from relapse longer than 8 years--a therapeutic cure? 188 75

The authors reviewed 89 patients treated for cerebellar medulloblastoma between 1970 and 1989 to determine the impact of changing treatment (high-dose posterior fossa radiation therapy and chemotherapy) on the pattern of failure in medulloblastoma. Between 1970 and 1983, 50 patients (median follow-up, 110 months) were treated with surgery and postoperative craniospinal irradiation (CSI). Nineteen of the 50 (38%) recurred in the central nervous system (CNS). Isolated systemic (bone) metastases occurred in six. The median time to the development of bone metastases was 12 months. Since 1984, 39 patients (median follow-up, 27 months) were treated with preradiation chemotherapy consisting of cisplatin and vincristine for 9 weeks before initiation of CSI. Nine of the 39 (23%) patients recurred in the CNS. There were no systemic failures in this cohort. The actuarial 5-year disease-free survival was 55 +/- 7% for the earlier cohort and 72 +/- 8% for the later cohort (P equals 0.3). Posterior fossa recurrence was associated with radiation therapy to this area. The cumulative incidence of posterior fossa relapse was 50 +/- 13% in patients who received less than 5300 cGy and 18 +/- 7% in those who received 5300 cGy or more (P equals 0.005). All six bone relapses were in patients treated with CSI alone and 5300 cGy or more to the posterior fossa for a 5-year cumulative incidence of bone metastases of 18 +/- 7% compared with 0% for patients treated with 5300 cGy or more and chemotherapy (P equals 0.03). The authors concluded that high-dose radiation therapy has altered the pattern of relapse with an increase in systemic recurrence after radiation therapy alone that is now equivalent to the risk of recurrence in the posterior fossa. Chemotherapy may be indicated in an attempt to decrease this high risk of systemic metastases.
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PMID:The change in patterns of relapse in medulloblastoma. 189 59

A case is reported in which a desmoplastic medulloblastoma metastasized to the pancreas and to the surrounding soft tissues but did not recur locally or disseminate within the central nervous system. Multidrug chemotherapy and local radiation therapy resulted in a complete remission. In all four previously reported cases of medulloblastoma metastasizing to the pancreas, the diagnosis was not made until the postmortem examination, and all of these patients also had extensive metastases in other organ systems. Modification of the Weiss criteria defining extraneural metastases from tumors of the central nervous system is suggested.
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PMID:Desmoplastic medulloblastoma metastatic to the pancreas: case report. 194 47

A consecutive series of 30 cases of extracranial medulloblastoma metastases in adults is analysed. The majority of the patients were males with a 3:1 male/female ratio. Bone was the most frequent site of metastases in adults (77%) and children (78%), followed by lymph nodes (33%) in both children and adults. Lung metastases were more common in adults (17%), but liver metastases occurred more frequently in children (15%). Possible routes of spread and development of metastases are discussed, with special emphasis on the role of shunts in tumour seeding. Distant extracranial metastatic spread of medulloblastoma occurs at the rate of 7.1%. Mean interval between operation of the primary tumour and the discovery of metastases was shorter in children (20 months) than in adults (36 months). Survival after the discovery of metastases was also shorter in children (5 months) than in adults (9.5 months). Shunts were associated with an earlier appearance of metastases and with a poorer prognosis. A detailed review of the literature of 119 cases of medulloblastoma with extracranial metastases is provided.
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PMID:Extracranial metastases of medulloblastoma in adults: literature review. 201 Jul 66

The authors reviewed the hospital charts of 415 pediatric patients treated for benign or malignant primary brain tumors over the past 20 years at the Children's Hospital Medical Center, Seattle. Patients' ages ranged from the neonatal period to 18 years. A shunt was placed in 152 patients (37%), 45 before and 94 after surgery. Confirmation of extraneural metastases was based on clinical and diagnostic examination. Factors analyzed as possibly influencing the occurrence of extraneural metastases were: 1) the shunt: type, valve, location, filter, and revisions; 2) extent of resection; 3) pathology; and 4) treatment regimen. Eight of the 415 patients developed extraneural metastases during life. All eight patients had a medulloblastoma (cerebellar primitive neuroectodermal tumor). These eight patients were separated into Group A (without a shunt) and Group B (with a shunt). In Group A (five patients), the mean interval from primary diagnosis to metastasis was 15 months. Two children had gross total resection of the tumor. The predominant location of metastases in Group A was: bone (two cases); cervical lymph nodes (one); lung/bone (one); and retroperitoneal pelvic mass (one). Three Group A patients had a simultaneous central nervous system (CNS) recurrence. Of the three Group B patients, two had a ventriculoperitoneal (VP) shunt and one a ventriculoatrial (VA) shunt; all were placed postoperatively. One Group B patient had a simultaneous CNS recurrence. No shunt revisions were performed in these three patients. The mean time from primary diagnosis to metastasis was 25 months. One patient had a total tumor resection. The predominant location of metastases was bone (one case), retroperitoneal pelvic mass (one), and abdominal cavity with ascites (one case). Only one patient in the entire series had a filter placed; this resulted in shunt obstruction and was removed 1 month following placement. It is concluded that cerebrospinal fluid shunts, regardless of type, location, revision rate, or filter insertion, do not predispose pediatric patients with brain tumors to develop extraneural metastases. A diagnosis of shunt-related metastases should be based on the development of intra-abdominal (VP shunt) or pulmonary (VA shunt) dissemination primarily with or without additional sites. The diagnosis of medulloblastoma is an important factor related to metastasis occurrence while the extent of resection and postoperative therapy are not influential.
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PMID:The risks of metastases from shunting in children with primary central nervous system tumors. 203 46

The spread of primary central nervous system (CNS) neoplasms beyond the confines of the neuraxis is a relatively uncommon observation. Extraneural metastases involving bone are quite rare, and have been observed almost exclusively in cases of medulloblastoma, high-grade (III-IV) astrocytoma, and glioblastoma multiforme. To date there has been only one case reported of bone metastasis from a "well-differentiated" astrocytoma. We now report two cases of astrocytoma in children with diffuse osteoblastic metastases and a fulminant clinical course. These cases demonstrate that due to the potential morphologic heterogeneity of these neoplasms, an initial biopsy diagnosis of low-grade astrocytoma does not always imply a benign clinical course.
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PMID:Osteoblastic metastases from astrocytomas: a report of two cases. 205 77

Nine children with medulloblastoma were treated at Chiba University Hospital from 1977 to 1983. Of these cases, metastases to the cribriform plate region were found in two cases. Portal film showed that cribriform-plate region was not included in a conventional whole-brain radiation port to shield the eyes. Since 1983, we have applied a newly designed radiation port to treat childhood medulloblastoma. The new method consists of two parallel, opposed, lateral ports including the cribriform plate and the first two cervical vertebrae, similar to Pinkel's method. It has been confirmed that this method covers completely the whole brain and is safe for the lens. A characteristic of our method is that the landmark of the lower margin of the radiation port can be easily delineated on the patient's face. We believe that this method contributes to the treatment of medulloblastoma.
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PMID:A newly designed radiation port for medulloblastoma to prevent metastasis to the cribriform plate region. 209 5

Studies of twenty-five patients with loculated leptomeningeal tumor metastases diagnosed by CT and/or MR were analyzed retrospectively. Medulloblastoma was the most frequent primary tumor (8/25, 32%). Four subgroups of loculated patterns were identified. Type A included mass(es) limited to the subarachnoid space without obvious direct parenchymal infiltration; this pattern occurred in 12 patients, of whom five had associated diffuse pattern. Type B was characterized by mass(es) still predominantly in the subarachnoid space but with minor transpinal parenchymal infiltration; this pattern was found in five patients. Type C comprised subarachnoid mass(es) with marked transpinal extension mimicking parenchymal lesion; this pattern was observed in three patients. Type D consisted of subarachnoid mass(es) growing along the perineural CSF space; this pattern was noted in two patients. Additionally, two patients presented with combined A and C patterns, and one patient had a combined B and C pattern. More than half the patients (14/25, 56%) presented with a single lesion. The most frequent locations were the suprasellar cistern, ventricular walls, and lateral recesses of the fourth ventricle, Gd-DTPA-enhanced T1-weighted MR images appeared best for demonstrating the site and extent of disease. Recognition of the loculated patterns of leptomeningeal metastases, which are less common than the diffuse pattern, is important to radiologists and clinicians for correct diagnosis and proper management of patients with this disease.
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PMID:Loculated intracranial leptomeningeal metastases: CT and MR characteristics. 210 30


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