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Risk factors of recurrence in 157 MB/PNET patients treated in one institution.

To evaluate the risk factors for recurrence of MB/PNET we analyzed the medical records of 157 patients treated at the Children's Memorial Health Institute between February 1981 and February 1997. The following factors were evaluated: age at diagnosis, gender, tumor size, tumor cells in the CSF, postoperative status, extent of resection and methods of treatment. We evaluated chemotherapy (CHT) doses, interval between courses, interval between surgery (S) and first course of CHT, interval between S and radiotherapy (RTX), and breaks during RTX. We divided patients into six groups: S alone, S+CHT, S+RTX, S+CHT+ RTX, S+RTX+CHT, S+CHT+RTX+ CHT. Age at diagnosis, gender, tumor size, extent of resection, postoperative status, intervals between courses of CHT, between S and the first course of CHT, and between S and RTX, and breaks during RTX had no statistical influence on relapse occurrence. Tumor cells in CSF were routinely checked for from January 1992 onward. In this group of 75 patients, 40 had tumor cells positive at surgery (28 relapsed), while in the group of 35 patients with negative tumor cells 14 relapsed (P=0.004). Out of 26 patients treated with S+RTX alone, 13 relapsed. Among 14 patients treated with S+RTX and prolonged CHT 6 relapsed. Out of 14 patients treated with S+CHT 13 relapsed; among 49 who received S+CHT+RTX 35 relapsed; and out of 51 patients treated with S+CHT+RTX+CHT 30 relapsed. In the multivariate analysis of treatment methods chemotherapy implemented after radiotherapy had a positive, though not statistically significant, influence on outcome (P=0.06). Among those receiving CHT the mean percentage of the ideal dose administered had a statistically significant influence on relapse: in the group of relapsed patients the mean dose was 76.1%, while in the group in continuous remission it was 83.7% (P=0.0013). On the basis of our data, we conclude that the presence of tumor cells in the CSF had a significant influence on the occurrence of relapse. Administration of appropriate doses of chemotherapy is extremely important for the occurrence of relapse and the final outcome of treatment. Prolonged adjuvant chemotherapy after radiotherapy seems to lower the risk of recurrence.

Antineoplastic Agents↗

Spermatic cord metastasis from a medulloblastoma.

A 4-year-old boy presented with metastases in the spermatic cord and ribs 2 years after treatment for a primary medulloblastoma (MB). The testis was free of tumor. A MB presenting with a metastasis to the spermatic cord has not been reported to date. The role of a ventriculo-peritoneal shunt in promoting such spread should be considered in planning management.

Bone Neoplasms↗

Expression of survivin, an inhibitor of apoptosis protein, in tumors of the nervous system.

Survivin is an inhibitor of apoptosis protein that blocks apoptosis by binding to caspases-3 and -7. It is highly expressed in less-differentiated embryonic cells and rapidly dividing tumors, but not in terminally differentiated adult tissues. Elevated survivin levels are found in malignant systemic tumors, and are associated with chemo-resistance, radiation resistance, and poor prognosis. However, expression of survivin in primary nervous system tumors has not been previously characterized. Immunohistochemistry using anti-human survivin antibody (SURV11-A) was performed on formalin-fixed, paraffin-embedded archival tissue from 112 primary central nervous system tumors. Survivin immunoreactivity was seen in most diffuse astrocytomas [WHO II (2/4), III (3/3), IV (9/10), giant-cell glioblastoma (1), and gliosarcoma (1)]. The intensity and degree of survivin expression showed trends with tumor grade, with glioblastomas having the highest positivity. Pilocytic astrocytomas (5) and pleomorphic xanthoastrocytoma (1) were positive to a lesser degree. In oligodendrogliomas (6) and mixed oligo-astrocytomas [grade II (5), II-III (3), and III (7)], oligodendroglial elements appear to be negative compared to positive mini-gemistocytic oligodendrocytes. Ependymomas [grade II (6) and grade III (1)] were positive. Medulloblastomas (5) and retinoblastoma (1/4) showed focal positivity. All meningiomas [grade I (12), II (9), III (4), and grade I (3) and II (5) with frank brain invasion] were intensely positive. All schwannomas (11) and neurofibromas (6) were intensely positive. Thus, survivin is expressed in the majority of the primary nervous system tumors, particularly in glioblastomas, meningiomas, schwannomas and neurofibromas. Overexpression of survivin in meningiomas and benign peripheral nerve sheath tumors contrasts with previous reports relating it to rapid division and poor prognosis.

Astrocytoma↗

Expression of alpha-, beta-, and gamma-synuclein in glial tumors and medulloblastomas.

alpha-, beta- and gamma-synuclein are highly homologous proteins that are found predominantly in neurons. Abnormal accumulation of synucleins has been associated with diseases of the central nervous system particularly Parkinson's disease. Immunoreactivity of alpha-synuclein is demonstrated in brain tumors with neuronal differentiation and in schwannomas, whereas gamma-synuclein has been demonstrated in breast and ovarian carcinomas. The immunoreactivity of synucleins has not been described in glial tumors. Immunoreactivity of synucleins in glial cells in culture and in pathological conditions, however, suggests that synucleins may be expressed by glial tumors. We studied the expression of alpha-, beta-, and gamma-synuclein in 84 human brain tumors (24 ependymomas, 31 astrocytomas, 8 oligodendrogliomas, and 21 medulloblastomas) by immunohistochemistry. Our study demonstrates immunoreactivity for gamma-synuclein in high-grade glial tumors; immunoreactivity is found in all anaplastic ependymomas but in only 33% of ependymomas and 16% of myxopapillary ependymomas. Immunoreactivity for gamma-synuclein is noted in 63% of glioblastomas but not in other astrocytic tumors. Of medulloblastomas, 76% have immunoreactivity for either alpha- or beta-synuclein or both; no immunoreactivity for gamma-synuclein is seen in medulloblastomas.

Astrocytes↗

Atypical teratoid/rhabdoid tumor of the central nervous system: a comparative study with primitive neuroectodermal tumor/medulloblastoma.

Eleven atypical teratoid/rhabdoid tumors (AT/RT) and 121 primitive neuroectodermal tumors/medulloblastomas (PNET/MB) were included in this study for evaluation of the histopathological features of AT/RT and comparison between AT/RT and PNET/MB. Histopathological studies of AT/RT showed that in addition to the commonly recognized components, i.e., rhabdoid cells, small (PNET/MB) cells, spindle cells and epithelial components, there was a previously unrecognized component, sickle-shaped embracing cells, which were present in all cases and could be useful as a histological marker of this tumor. Immunohistochemical studies showed divergent differentiation of the tumor cells and among the 16 antibodies studied, vimentin, neuron-specific enolase, epithelial membrane antigen and glial fibrillary acidic protein were most commonly reactive. The frequency of AT/RT expressed as a ratio of AT/RT to PNET/MB was 1:11 in general and increased to 1:3.8 among patients younger than 3 years old. The AT/RT patients were younger than those with PNET/MB and had a female predominance. The MIB-1 labeling index of AT/RT was significantly higher than that of PNET/MB (mean 63.9 vs 40.1), which correlated with a shorter survival in patients with AT/RT than those with PNET/MB (median survival time 15.4 months vs 156.4 months).

Antigens, Nuclear↗

Cavernous malformation after radiation therapy for astrocytoma in adult patients: report of 2 cases.

Radiation-induced cavernous malformations are rarely reported, and most cases have been children. We describe two adult patients with cavernous malformation after irradiation for astrocytoma. Magnetic resonance (MR) imaging, at their ages of 53 years, showed a cavernous malformation in the irradiated field 26 and 10 years after resection and irradiation, respectively. Cavernous malformations were confirmed by the histopathological examination in the both cases. Radiation-induced cavernous malformations are rare in adult patients with astrocytoma. One reason why we found two such cases was that these patients had been successfully treated for astrocytoma and had long follow-up periods.

Astrocytoma↗

Embryonal tumors in the adult population: implications in therapeutic planning.

The natural history of neuroectodermal tumors is still debated as far as prognostic factors are concerned; the same uncertainty applies to the optimal radiotherapy schedule and even more to the presumptive additive effect of chemotherapy. The rarity of these tumors and the heterogeneity of management make interpretation of literature data also more difficult. We evaluated clinical course in a cohort of 39 patients, including 31 with medulloblastoma (MB) and 8 with primitive neuroectodermal tumors (PNET). All patients were treated with radiotherapy, a standardized chemotherapy protocol including PCV scheme, and a second-line chemotherapy with cisplatin and etoposide (VP16) at recurrence. In 27 patients, intrathecal chemotherapy was also delivered. Median follow-up was 10.8 years. Overall, PNET had a worse outcome as compared to MB: median survival times were 42.8 vs. 92.6 months, respectively (p = 0.05). At 5 years, 45% of MB patients are alive. No significant difference in disease-free period was found between patients of different age, desmoplastic variant, tumor localization, or extent of surgery. Patients considered to be "high risk" had a significantly shorter disease-free period as compared with low-risk patients (27 vs. 54.7 months, p = 0.04). Systemic or intrathecal chemotherapy did not influence progression-free survival (PFS). However, in the majority of chemotherapy-treated patients, a low-dose craniospinal radiotherapy was also delivered. This combination of treatments may have avoided the expected increased percentage of failure. Moreover, more than half of recurrent patients had a partial response to chemotherapy that extended survival for approximately 3 years. Repeated surgery and chemotherapy at recurrence favorably influenced survival time.

Adult↗

Progress and challenges in childhood brain tumors.

Although many challenges lie ahead, there has been definite progress made in the management of childhood brain tumors. Some of these advances have increased progression-free and overall survival. Other advances, while not improving survival, have resulted in a better quality of life for long-term survivors. Probably the best example of progress is manifest in the outcome of children with medulloblastoma. Seventy percent, and in some subsets as high as 80% of children with this disease can be expected to be cured, compared to approximately 50% three decades ago. This improvement in disease control has been associated with a reduction in the dose of radiotherapy for many patients and possibly an improved quality of survival. For other tumor types, especially brain stem gliomas, there has been little progress made. A primary challenge in the years ahead will be how to integrate biologic discoveries into the care of children for brain tumors, with the hope that molecular biologically based therapy will be more effective and improve the quality of life for survivors.

Brain Neoplasms↗

The therapy of infantile malignant brain tumors: current status?

Malignant brain tumors are not uncommon in infants as their occurrence before the age of three represents 20-25% of all malignant brain tumors in childhood [1]. Genetic predisposition to infantile malignant brain tumors are known in Gorlin syndrome for example who present with desmoplastic medulloblastoma in about 5% of the affected patients. In addition, sequelae from tumor and its treatment are more severe at this age [2]. Thus, malignant brain tumors represent a true therapeutic challenge in neuro-oncology. Before the era of modern imaging and modern neurosurgery these malignant brain tumors were misdiagnosed or could not benefit of the surgical procedures as well as older children because of increased risks in this age group. Since the end of the 80s, noninvasive imaging procedures produce accurate diagnosis of brain tumors and improvement in neurosurgery, neuroanesthesia and perioperative intensive care permit safe tumor resections or at least biopsies. Consequently, the pediatric oncologists are more often confronted with very young children who need a complementary treatment. Before the development of specific approaches for this age group, these children received the same kind of treatment than the older children did, but their survival and quality of life were significantly worse. The reasons of these poor results were probably due in part to the fear of late effects induced by radiation therapy, leading to decrease the necessary doses of irradiation which increased treatment failures without avoiding treatment related complications [3]. At the end of the 80s, pilot studies were performed using postoperative chemotherapy in young medulloblastoma patients. Van Eys treated 12 selected children with medulloblastoma with MOPP regimen and without irradiation; 8 of them were reported to be long term survivors [4]. Subsequently, the pediatric oncology cooperative groups studies have designed therapeutic trials for very young children with malignant brain tumors. Different approaches have been explored: * Prolonged postoperative chemotherapy and delayed irradiation as designed in the POG (Pediatric Oncology Group). * Postoperative chemotherapy without irradiation in the SFOP (Société Française d'Oncologie Pédiatrique) and in the GPO (German Pediatric Oncology) studies. * The role of high-dose chemotherapy with autologous stem cells transplantation was explored in different ways: High-dose chemotherapy given in all patients as proposed in the Head Start protocol. High-dose chemotherapy given in relapsing patients as salvage treatment in the French strategy. In the earliest trials, the same therapy was applied to all histological types of malignant brain tumors and whatever the initial extension of the disease. This attitude was justified by the complexity of the classification of all brain tumors that has evolved over the past few decades leading to discrepancy between the diagnosis of different pathologists for a same tumor specimen. Furthermore, it has become increasingly obvious that the biology of brain tumors in very young children is different from that seen in older children. However, in the analysis of these trials an effort was made to give the results for each histological groups, according to the WHO classification and after a central review of the tumor specimens. All these collected data have brought to an increased knowledge of infantile malignant brain tumors in terms of diagnosis, prognostic factors and response to chemotherapy. Furthermore a large effort was made to study long term side effects as endocrinopathies, cognitive deficits, cosmetic alterations and finally quality of life in long term survivors. Prospective study of sequelae can bring information on the impact of the different factors as hydrocephalus, location of the tumor, surgical complications, chemotherapy toxicity and irradiation modalities. With these informations it is now possible to design therapeutic trials devoted to each histological types, adapted to pronostic factors and more accurate treatment to decrease long term sequelae.

Antineoplastic Combined Chemotherapy Protocols↗

Radiation induced adult medulloblastoma: a case report.

Adult medulloblastoma is a rare intracranial tumor. Our patient is a 61 year old woman treated with cranial irradiation 15 years previously for a low grade astrocytoma in the left posterior temporal lobe that was recently diagnosed with medulloblastoma in the right cerebellum. This is the first reported case of radiation induced adult medulloblastoma.

Astrocytoma↗

Medulloblastomas and central nervous system primitive neuroectodermal tumors.

Significant advances in the treatment of medulloblastoma and primitive neuroectodermal tumors have been made in the past three decades. Maximal surgical resection is a mainstay of therapy. However, unlike many other central nervous system neoplasms, medulloblastoma and primitive neuroectodermal tumors are radiation and chemotherapy responsive. Despite this response, the prognosis for patients with these tumors remains variable and is relatively poor in infants and patients with metastatic disease. These tumors most commonly arise in children, thus most clinical trials emphasize the reduction of long-term sequelae, in addition to improving survival. All newly diagnosed patients who are eligible should be offered participation in a clinical trial. If a patient is ineligible or declines consent/assent for a clinical trial, the best current treatment approach is surgical resection, followed by radiation therapy (except for children younger than 3 years) with weekly vincristine. For high-risk patients, 36 Gy of craniospinal irradiation should be delivered plus a boost of 19.8 Gy to the posterior fossa/primary tumor bed and sites of bulk metastatic disease. For average-risk patients, the craniospinal irradiation dose may be lowered to 23.4 Gy plus 32.4 Gy to the posterior fossa/tumor bed. After radiation therapy, intensive multimodal chemotherapy should be used for all patients.

Antineoplastic Agents↗

Pneumocystis carinii pneumonia during steroid taper in patients with primary brain tumors.

Pneumocystis carinii causes life-threatening pneumonitis (PCP) in immunocompromised individuals. In the non-AIDS (acquired immunodeficiency syndrome) population, PCP is frequently associated with corticosteroid therapy, and the rodent model uses corticosteroid-induced immunosuppression to provoke PCP. Although patients with intracranial tumors are frequently treated with long courses of corticosteroids, there have been very few descriptions of PCP in this population. We report the diagnosis and treatment of PCP in four patients over a 12-month period with intracranial neoplasms who developed symptoms during corticosteroid taper. Effective prophylaxis against PCP exists and should be considered for patients with intracranial neoplasms receiving long-term steroids.

Aged↗

Enolase distribution in human brain tumors, retinoblastomas and pituitary adenomas.

The cellular localization of alpha-, beta- and gamma-subunits of enolase isoenzyme was studied immunohistochemically in various human brain tumors, retinoblastomas and pituitary adenomas (total, 91 cases). The alpha-subunit was found in almost all brain tumors except in medulloblastoma cases. A case of medullomyoblastoma contained beta-subunit-positive myoblastic cells, which was also positive for human myoglobin. The gamma-subunit was frequently observed in medulloblastomas, retinoblastomas and pituitary adenomas. However, gamma-subunit was also present in some non-neuronal brain tumors such as astrocytomas and oligodendrogliomas. Enzyme immunoassay technique also confirmed the presence of gamma-subunit in a medulloblastoma and two retinoblastomas.

Adenoma↗