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PubMed1998

Telomerase activity and alterations in telomere length in human brain tumors.

Telomerase activity was examined in 170 human brain tumor tissues, and terminal restriction fragment (TRF) length was examined in 152 of the 170. Telomerase activity was detected in 61.7% (66 of 107) of the neuroepithelial tumors. However, the detection rates of telomerase activity were widely different for different histopathological entities. In the case of astrocytic tumors, the detection rate was 20.0% (3 of 15) for grade II astrocytomas, 40.0% (6 of 15) for anaplastic astrocytomas, and 72.3% (34 of 47) for glioblastomas. The mean TRF length of the tumors with telomerase activity was significantly shorter than that of the tumors with undetectable telomerase activity for each tumor entity. In grade II and anaplastic astrocytomas, telomerase activity was an indicator of early histological progression and reduced survival of the patients, although there was no difference in MIB-1 staining indices between the tumors with and without telomerase activity at onset. In three astrocytic tumors, concurrence of telomere shortening and telomerase reactivation was observed at recurrence; in these cases, tumors progressed to a higher grade. Ten glioblastomas that progressed from lower-grade tumors exhibited telomerase activity, and their TRF lengths were reduced in 80% (8 of 10). In contrast, telomerase activity was detected in only 63.3% (19 of 30; P < 0.05) and the TRF length remained compatible with normal values in 56.7% (17 of 30; P < 0.01) of de novo glioblastomas. Thus, telomerase activity strongly correlated with potential tumor progression in the short term as well as with progression itself of the astrocytic tumors, whereas telomeres may still have been in the process of shortening in some of the de novo glioblastomas. High telomerase activity was exhibited in all primitive neuroectodermal tumors, anaplastic oligoastrocytomas, neuroblastomas, and oligodendrogliomas. TRF length was reduced in the majority (14 of 15) of three previously high-grade tumors, whereas it was compatible with that of normal brain tissues in the oligodendrogliomas, suggesting that telomerase activity with shortened telomeres correlates with the aggressive growth of high-grade neuroepithelial tumors. Tumor cell lines could be established from 17.2% (5 of 29) of neuroepithelial tumors with telomerase activity but not from tumors without this activity (P < 0.05), suggesting that telomerase reactivation is an essential event in the neuroepithelial cell immortalization in vitro. In nonneuroepithelial tumors, telomerase activity was detected in malignant tumors, such as germ cell tumors, lymphomas, metastatic adenocarcinomas, hemangiopericytomas, and an anaplastic meningioma. In contrast, such activity was not detected in benign tumors, including meningiomas, pituitary adenomas, hemangioblastomas and schwannomas, except for one hemangioblastoma that recurred four times and displayed malignant features at the fourth recurrence. These findings suggest that telomerase activity can be an index of malignant potential or malignancy itself in nonneuroepithelial brain tumors.

Adolescent↗
PubMed2001

Extraskeletal Ewing sarcoma in a 77-year-old woman.

Extraskeletal Ewing sarcoma (EES) is a rare soft tissue tumor that is morphologically indistinguishable from Ewing sarcoma of bone. It is usually found in young people, but several cases have occurred in patients older than 50 years. The differential diagnoses include other small, blue round cell tumors (SBRCTs) and other members of the Ewing family of tumors such as the primitive neuroectodermal tumor. We present a case of EES in the left inguinal region of a 77-year-old woman. The tumor was distinguished from other SBRCTs by lack of immunoreactivity for epithelial, lymphoid, vascular, neuroendocrine, neural, histiocytic, and muscle markers. Primitive neuroectodermal tumor was excluded because of the lack of neural differentiation by histologic analysis, immunohistochemistry, and electron microscopy. Extraskeletal Ewing sarcoma was confirmed by characteristic features on histologic analysis, histochemistry, immunohistochemistry, and electron microscopy and by the presence of the t(11;22)(q24;q12) fusion transcript detected by reverse transcriptase-polymerase chain reaction. This case serves to remind the reader that EES is not a tumor that occurs exclusively in young patients.

Aged↗
PubMed2001

PDGF-C is an EWS/FLI induced transforming growth factor in Ewing family tumors.

The aberrant transcription factors associated with many human malignancies function by deregulation of tumorigenic pathways. However, identification of these pathways has come slowly. Virtually all cases of Ewing's Sarcoma and peripheral Primitive Neuroectodermal Tumor (PNET) are associated with aberrant transcription factors which fuse amino-terminal EWS with the DNA binding moiety of an ETS transcription factor (FLI-1 in 90% of cases). Attempts to identify the downstream targets of these chimeras in the Ewing Family Tumors (EFT) on the basis of differential gene regulation have produced little association with tumor biology. As an alternative approach, we have used highly efficient retroviral systems to biologically screen cDNA derived from cells transformed by EWS/FLI-1. We have identified the recently described PDGF-C as target of EWS/ETS transcriptional deregulation. This transcriptional deregulation is specific to EWS/FLI. PDGF-C possesses substantial biologic activity in vitro and in vivo. It is expressed in EFT cell lines and in primary tumors. Within these EFT cell lines, PDGF-C expression is dependent upon EWS/FLI activity. These results suggest that PDGF-C may be a significant mediator of EWS/FLI driven oncogenesis.

3T3 Cells↗
PubMed1994

Malignant laryngeal tumors in children: a 15-year experience with four patients.

Malignant laryngeal neoplasms in children are uncommon and present diagnostic and therapeutic challenges. A 15-year retrospective review of laryngeal tumors at our institution identified four patients with malignant neoplasms. These children, 7 months to 16 years of age, were treated for squamous cell carcinoma, choriocarcinoma, rhabdomyosarcoma, and primitive neuroectodermal tumor. This report details these cases, emphasizing diagnostic approaches, treatment decisions (medical oncologic management, surgical resection), and rehabilitation measures for postlaryngectomy communication. A multi-institutional pediatric head and neck tumor registry would be a useful reference to assist with individual treatment decisions.

Adolescent↗
PubMed2004

Radiotherapy for pediatric central nervous system tumors: a regional cancer centre experience.

INTRODUCTION: The purpose of this review was to analyze outcomes for pediatric patients treated for more common (non-low grade glioma) primary central nervous system (CNS) tumors at a Regional (tertiary) Cancer Center. Comparison to reported results from other regional centres and results from the contemporary literature were made. MATERIAL AND METHODS: The records of pediatric patients treated with radiotherapy at the London Regional Cancer Center (LRCC) for more common (non-low grade glioma) primary CNS tumors between 1980 and 2001 were reviewed. Details regarding tumor presentation, treatment and outcome were analyzed. RESULTS: Eighty-eight patients were eligible for the review. Twenty-nine patients with malignant glioma, 37 patients with medulloblastoma or primitive neuroectodermal tumor (PNET), 15 patients with brainstem glioma, 4 with ependymoma and 3 with germ cell tumors were treated during this time period. Average follow-up for the group was 5 years (range 4 months to 19 years). Five-year overall, progression free and cause specific survival were 45, 42 and 50%, respectively. For patients with malignant glioma median progression free and overall survival was 20 and 29 months. For patients with brainstem glioma median progression free and overall survival was 9 and 13 months. For medulloblastoma, 5-year progression free, and overall survival was 60 and 59%. CONCLUSIONS: RESULTS of this retrospective review of pediatric patients treated at a regional cancer center for primary CNS tumors (other than low grade glioma) were comparable to contemporary results reported by other Canadian centers and North American co-operative group trials.

Adolescent↗
PubMed1993

Intraarterial cisplatinum and intravenous adriamycin for primary hypervascular bone tumor: experience of seven cases.

Seven consecutive cases of primary hypervascular bone tumor, encountered between January 1991 and September 1992, were treated with intraarterial cisplatinum and intravenous adriamycin infusion. There were four osteosarcomas, one malignant fibrous histiocytoma, one chondrosarcoma and one case of primitive neuroectodermal tumor. Local symptoms were markedly relieved, or disappeared, in 71% (5/7) of cases after the first course of treatment. Sclerotic changes of bone tumor occurred in 100% (6/6) of cases after two courses of chemotherapy. Progressive decrease of tumor stains was noted in 100% (6/6) of patients during angiographic assessments. On exploration, no gross tumors were found in 80% (4/5) of the cases that received limb-sparing surgery. Although disappearance of symptoms and sclerotic changes of bone tumor predicted a good response to treatment, the degree of decrease of tumor stains corresponded best with the extent of tumor necrosis. Our study verified the effectiveness of intraarterial cisplatinum and intravenous adriamycin infusion in treating primary hypervascular bone sarcomas. Further studies with more cases are necessary to define the optimal duration of postoperative adjuvant chemotherapy.

Adolescent↗
PubMed1993

Use of HBA 71 and anti-beta 2-microglobulin to distinguish peripheral neuroepithelioma from neuroblastoma.

Peripheral neuroepithelioma (PN) can be difficult to distinguish from undifferentiated neuroblastoma (NBL) in the absence of molecular and cytogenetic studies. These primitive neural tumors of childhood are similar in morphology and immunocytochemistry, despite their distinct biochemical and behavioral characteristics. The recently developed monoclonal antibody HBA 71 is specific for the product MIC2, a marker of peripheral primitive neuroectodermal tumors. Because beta 2-microglobulin also is selectively expressed by most tumors in this subset, we examined whether a combination of the antibodies HBA 71 and anti-beta 2-microglobulin could facilitate the differentiation of the two malignancies. We histologically confirmed the diagnoses of 45 paraffin-embedded tumors of presumed neuroectodermal origin (19 PNs and 26 NBLs) from the pathology files of St Jude Children's Research Hospital. Samples were immunohistochemically stained using HBA 71 and anti-beta 2-microglobulin. Molecular and cytogenetic data were correlated with the results in a subset of eight patients. Sixteen (84%) of the 19 PNs reacted with HBA 71 and 13 (76%) of 17 PNs reacted with anti-beta 2-microglobulin. None of the NBLs reacted with either antibody. Three PNs were identified by HBA 71 alone and one was identified by anti-beta 2-microglobulin alone. Cellular genetic findings were consistent with the results. HBA 71 and anti-beta 2-microglobulin, when used in combination, can facilitate the differential diagnosis of PN and NBL.

12E7 Antigen↗
PubMed1998

Primary cutaneous Ewing's sarcoma: immunophenotypic and molecular cytogenetic evaluation of five cases.

Cutaneous small blue cell tumors are relatively uncommon and include primary lesions of either adnexal or neuroendocrine differentiation, as well as metastatic disease. Extraosseous Ewing's sarcoma/malignant primitive neuroectodermal tumor (MPNET) rarely may occur as a primary, superficially based neoplasm in children and young adults. We describe a series of five cases of Ewing's sarcoma/malignant primitive neuroectodermal tumor occurring as a primary cutaneous malignancy supported diagnostically both by immunohistochemical stains and fluorescence in situ hybridization (FISH). All five cases occurred as a solitary dermal nodule and were located in the lower extremities (3 cases), the axilla (1 case), and the flank (1 case). Three of the cases were clinically polypoid. Four of the five patients were female, and age at presentation ranged form 8 to 50 years of age (median, 18 years). All five tumors consisted of nodular proliferations of monomorphous, small blue cells with round, vesicular nuclei, and scant to moderate cytoplasm that were uniformly immunoreactive for the CD99 cell surface glycoprotein in a characteristic membranous pattern. Fluorescence in situ hybridization analysis of paraffin-embedded tissue revealed that three of four tumors were positive for a chromosomal translocation involving the EWS locus at 22q12, seen in more than 90% of cases of Ewing's sarcoma/malignant primitive neuroectodermal tumor. One case was not analyzable. All five patients were treated using local excision, and two patients additionally received postoperative chemotherapy and radiotherapy. Clinical follow-up is available in three cases (median duration, 33 months) and to date none has shown evidence of either local recurrence or metastasis. Because similar cases reported in the literature have likewise had favorable clinical courses after excision, primary cutaneous Ewing's sarcoma/malignant primitive neuroectodermal tumor may represent a clinically favorable subset of this otherwise highly aggressive neoplasm.

Adolescent↗
PubMed1995

A phase I and II trial of dose-intensified cyclophosphamide and GM-CSF in pediatric malignant brain tumors.

PURPOSE: Cyclophosphamide is commonly used in the treatment of children with malignant brain tumors. The purpose of this study was to develop a multicycle, high-dose intensity cyclophosphamide regimen with granulocyte-macrophage colony-stimulating factor (GM-CSF) and to assess its activity against malignant glioma and primitive neuroectodermal tumor (PNET). METHODS: Twenty-three patients with brain tumors, including 15 with malignant glioma and six with PNET, were enrolled. Cyclophosphamide (1.8-2.25 g/m2/day for 2 days i.v.; total dose 3.6-4.5 g/m2) was administered and was followed by recombinant human GM-CSF (5 micrograms/kg/day s.c.) on days 3-11 or until the absolute granulocyte count reached 1.5 x 10(9)/L. RESULTS: With a total of 83 cycles administered, the mean dose intensity of cyclophosphamide ranged from 1.5 g/m2/week through cycle 2 (22 patients) to 0.8 g/m2/week through cycle 8 (two patients). No activity was seen against malignant glioma, and five of six patients with PNET had partial responses. The mean duration of a neutrophil count of < 0.5 x 10(9)/L was only 8 days; the platelet recovery was substantially longer. Fever during neutropenia occurred in 54 of 83 cycles. One patient died from transfusion-related graft-versus-host disease. CONCLUSIONS: A cyclophosphamide regimen equal to twice the dose intensity of that used in conventional therapy was administered. The regimen was active against PNET but inactive against malignant glioma.

Adolescent↗
PubMed2005

Favorable outcome of Ewing sarcoma family tumors to multiagent intensive preoperative chemotherapy: a single institution experience.

BACKGROUND: Aim of our study was to evaluate the efficacy of multiagent intensive preoperative chemotherapy in patients with Ewing sarcoma family tumors (ESFT), in order to succeed a better percentage of necrosis before surgical resection. PROCEDURE: Eighteen patients with ESFT were treated with the same multiagent intensive preoperative protocol. 5/18 patients had bone Ewings sarcoma (EWS) and 13/18 had peripheral primitive neuroectodermal tumor (PNET). None had metastases at diagnosis. Chemotherapy consisted of 5 or 6 cycles with vincristine, cisplatin, cyclophosphamide, and Adriamycin, followed by 12 cycles of vincristine, cyclophosphamide, and actinomycin-D. Five patients with EWS underwent total resection after 5-6 cycles of preoperative chemotherapy and prosthetic replacement was performed in two of them. In 3/13 patients with PNET the tumor was resected at diagnosis and in 1/13 after 5 cycles of chemotherapy, while 9/13 patients received chemotherapy only and/or radiotherapy. RESULTS: In patients with EWS, the histologic specimens of the resected tumors showed that tissue necrosis was 100% in four patients and 95% in one patient. The good histologic response reflects the effectiveness of this regimen in all ESFT. No patient had topical recurrence or developed metastatic disease during follow-up period (2-13 years, mean time 7.4 years). All patients had the scheduled cycles without delays or dose reductions. There were no major side effects of chemotherapy. CONCLUSIONS: The intensive chemotherapy schedule, comprising of 5-6 cycles preoperatively, seems to maximize the percentage of tumor necrosis, thus improving outcome. Our study implies that this combined therapy may improve the prognosis of ESFT.

Adolescent↗
PubMed1995

Neurologic and other disorders in relatives of pediatric patients with CNS tumors.

Abnormalities of embryogenesis and nervous system development may cause or contribute to the development of childhood brain tumors. To identify genetic or environmental factors that may be associated with etiologies of childhood central nervous system tumors, we examined family histories of 165 children with such tumors for the presence of neurologic disorders, including neural tube defects, mental retardation, seizures, and central nervous system tumors, as well as other cancers and birth defects. Only 1 patient, with the neurofibromatosis-Noonan syndrome, was confirmed to have an underlying syndromic diagnosis associated with central nervous system tumorigenesis. Families of 2 probands with posterior fossa primitive neuroectodermal tumors reported relatives with olivopontocerebellar atrophy. Although increased incidences of study disorders were not identified in this population, it is possible that within individual families one or more of these disorders is related to childhood central nervous system tumorigenesis.

Adolescent↗
PubMed2002

Nonteratomatous tumors in the pediatric sacral region.

STUDY DESIGN: Two institutional experiences in nonteratomatous sacral tumors of the child were analyzed retrospectively. OBJECTIVES: To examine noncongenital nonteratomatous sacral tumors, which are more common in older infants and, as a group, are rare. SUMMARY OF BACKGROUND DATA: Pediatric sacral tumors usually occur in the newborn period, with most of these tumors being sacrococcygeal teratomas. Other common benign congenital tumors of the sacrum include lipomas, dermoids, and epidermoids. METHODS: Six patients were found in a 6-year period. Four patients underwent posterior resection of their tumors. One underwent a combined anterior and posterior approach. One patient underwent a posterior resection and will undergo a second stage anterior approach later to allow for chemotherapy and radiation to shrink the intrapelvic portion of the tumor. RESULTS: Ages ranged from 8 to 11 years. Three were males, and three were females. Five of six presented with back pain, three had constipation, and two had gait difficulties. Pathologies were diverse. They included ganglioneuroma (n = 1), myxopapillary ependymoma (n = 2), primitive neuroectodermal tumor (n = 1), aneurysmal bone cyst (n = 1), and Ewing's sarcoma (n = 1). No progression of disease has occurred in the follow-up period of 1.5 to 7 years (average, 5 years). Radical resection did not result in instability. CONCLUSIONS: In contradistinction to adults, in whom chordomas and metastases are the most common primary and secondary tumors, the pediatric group does not have a predominant pathology. Tumors may attain extremely large sizes and may be very vascular. Multiple therapeutic methods may be required, including adjuvant chemotherapy and, possibly, embolization. Because of the wide range of pathologies, prognosis is varied.

Back Pain↗
PubMed2005

Immunohistochemical findings in embryonal small round cell tumors with molecular diagnostic confirmation.

The diagnosis of pediatric tumors relies heavily on immunohistochemical staining of small tissue biopsies, since many entities share a "small blue cell" phenotype. More recently, molecular genetic analysis for detection of specific gene fusion products has become available. With the increased use of such molecular techniques, the authors have noted that tumors with proven molecular diagnoses can exhibit unusual patterns of immunohistochemical staining. This study examines pediatric tumors with a "small blue cell" phenotype in which molecular diagnoses were available where applicable. A panel of immunohistochemical stains was performed (S100, CD56, NB84, CD99 [MIC2], Bcl-2, CD117, CD34, desmin, MNF116, and WT1). In the 370 sections from 37 cases, all primitive neuroectodermal tumors, with and without the presence of t(11;22), demonstrated uniform membranous membrane staining with CD99 (MIC2) and focal staining with CD56, NB84, MNF116, and WT1. All rhabdomyosarcomas, both alveolar and embryonal, demonstrated uniform desmin, CD56, and cytoplasmic WT1 immunostaining. Desmoplastic small round cell tumors showed positive cytokeratin staining, with half having "dot-like" cytoplasmic desmin and WT1 positivity; some showed focal positivity for NB84, CD99, and Bcl-2. The "undifferentiated" sarcomas showed the widest range of staining, with no marker staining all cases. Neuroblastomas exhibited uniform strong staining for CD56 and NB84 and marked cytoplasmic Bcl-2 positivity, and some cases showed cytoplasmic WT1 expression. Blastematous Wilms' tumors showed uniform strong membranous staining for CD56, uniform cytoplasmic staining for Bcl-2, and nuclear expression of WT1. Embryonal pediatric malignancies can demonstrate apparently nonspecific expression patterns for several antigens, which may reflect developmental immaturity rather than specific differentiation pathways.

Antibodies, Monoclonal↗
PubMed2004

Loss of cell polarity causes severe brain dysplasia in Lgl1 knockout mice.

Disruption of cell polarity is seen in many cancers; however, it is generally considered a late event in tumor progression. Lethal giant larvae (Lgl) has been implicated in maintenance of cell polarity in Drosophila and cultured mammalian cells. We now show that loss of Lgl1 in mice results in formation of neuroepithelial rosette-like structures, similar to the neuroblastic rosettes in human primitive neuroectodermal tumors. The newborn Lgl1(-/-) pups develop severe hydrocephalus and die neonatally. A large proportion of Lgl1(-/-) neural progenitor cells fail to exit the cell cycle and differentiate, and, instead, continue to proliferate and die by apoptosis. Dividing Lgl1(-/-) cells are unable to asymmetrically localize the Notch inhibitor Numb, and the resulting failure of asymmetric cell divisions may be responsible for the hyperproliferation and the lack of differentiation. These results reveal a critical role for mammalian Lgl1 in regulating of proliferation, differentiation, and tissue organization and demonstrate a potential causative role of disruption of cell polarity in neoplastic transformation of neuroepithelial cells.

Animals↗
PubMed2003

Chemotherapy for teratoma with malignant transformation.

PURPOSE: Teratoma with malignant transformation (MT) is a well-described entity that refers to the MT of a somatic teratomatous component in a germ cell tumor (GCT) to a histology that is identical to a somatic malignancy (eg, rhabdomyosarcoma [RMS]). Surgical resection has been the mainstay of therapy for localized transformed disease because these tumors are thought to be resistant to standard treatment. We report that chemotherapy has a role in selected patients with MT, determined by cell type. PATIENTS AND METHODS: Chemotherapy was administered to 12 patients with MT of GCT limited to a single cell type (two patients with primitive neuroectodermal tumors, five with undifferentiated RMS, one with anaplastic small-cell tumor, two with adenocarcinoma, and two with leukemia); 10 patients had measurable disease. GCT origin was confirmed by molecular cytogenetics in five patients. Each patient received chemotherapy regimens based on the specific malignant cell observed in the transformed histology. RESULTS: Seven patients with measurable disease achieved a partial response, with the duration of response ranging between 1 month and 7 years. Three of those patients are alive. Three patients did not respond to treatment, and all of those patients died as a result of their disease. CONCLUSION: Chemotherapy for MT limited to a single cell type may result in major responses and long-term survival in selected patients. Local therapy after chemotherapy is an important component of treatment to achieve maximum response.

Adenocarcinoma↗
PubMed2002

High-dose chemotherapy in poor-prognosis adult small round-cell tumors: clinical and molecular results from a prospective study.

PURPOSE: The prognosis of metastatic/high-risk localized small round-cell tumors (SRCTs) treated conventionally is dismal. In this phase II study, we explored a high-dose chemotherapy (HD-CT) approach and analyzed the clinical significance of fusion transcripts detection. PATIENTS AND METHODS: From June 1997 to November 1999, 28 SRCT patients (median age, 26 years; 14 peripheral primitive neuroectodermal tumors [pPNETs], seven rhabdomyosarcomas [RMSs], and seven desmoplastic small round-cell tumors [DSRCTs]) received induction chemotherapy with ifosfamide, epirubicin, and vincristine followed by HD-CT. Local treatment (radiotherapy and/or surgery) was performed when possible. Molecular analysis was performed on peripheral-blood and leukapheresis products by reverse-transcriptase polymerase chain reaction. RESULTS: Overall response (OR) was 65% (18 of 28), with 40% complete response and 25% partial response. According to histology, the OR rate was 86% in pPNET and 43% in both RMS DSRCT. With a median follow-up of 35 months, median overall survival was 16 months and median progression-free survival (PFS) was 10 months. PFS was statistically better in pPNET than other histologic types (P =.0045). No correlation was found between the fusion transcript and clinical outcome during follow-up. Furthermore, transcript detection in leukapheretic products was not of prognostic significance. CONCLUSION: Intensive HD-CT seems to enhance the response rate and survival when compared with conventional treatment in poor-prognosis pPNET. The poor results of this treatment in RMS and DSRCT do not support the inclusion of such an approach in these patient subsets. No definitive conclusions can currently be drawn concerning the clinical implications of the detection of fusion transcripts during treatment or follow-up.

Adolescent↗
PubMed1998

Diagnostic utility of MIC-2 immunocytochemical staining in the differential diagnosis of small blue cell tumors.

Ewing's sarcoma (ES) and peripheral neuroectodermal tumor (PNET) are considered in the differential diagnosis of small round blue cell tumors of infancy and childhood which includes neuroblastoma, rhabdomyosarcoma and malignant lymphoma. Fine-needle aspiration diagnosis of these neoplasms can be particularly difficult when the neoplasms are composed of poorly differentiated cells or fail to produce a stroma. MIC-2 is a highly sensitive and specific marker for the PNET/ES group of neoplasms and has been studied extensively in surgical pathology. Other small blue cell neoplasms including rhabdomyosarcoma, blastemal Wilm's tumor, and lymphoblastic lymphoma have also shown positivity, but the staining reactions are usually weak and focal. The utility of this marker in the differential of small blue cell neoplasms in cytologic material has not been examined. Twenty cases of small blue cell neoplasms obtained by fine-needle aspiration (FNA) were studied. MIC-2 antibody was applied retrospectively to formalin-fixed cell block material and destained alcohol-fixed and air-dried cytologic preparations. These cases include primitive neuroectodermal tumor (five cases), Ewing's sarcoma (two cases), neuroblastoma (four cases), Wilms's tumor (four cases), lymphoblastic lymphoma (two cases), and small-cell carcinoma (three cases). The cases were judged positive when the majority of the cells showed cytoplasmic staining. Diffuse cytoplasmic staining was observed in all seven cases of PNET/ES. Staining could be seen on the destained air-dried smears (three cases), fixed smears (two cases), or the cell block material (two cases). None of the other 13 small blue cell neoplasms showed positive staining. We conclude that MIC-2 is a sensitive and specific marker for the PNET/ES group of neoplasms in specimens from formalin-fixed cell block, air-dried, and alcohol-fixed cytologic material and is useful in the differential diagnosis of small blue cell tumors.

12E7 Antigen↗
PubMed2005

Multiagent chemotherapy and deferred radiotherapy in infants with malignant brain tumors: a report from the Children's Cancer Group.

PURPOSE: To evaluate response rate, event-free survival (EFS), and toxicity of two chemotherapeutic regimens for treatment of children younger than 36 months with malignant brain tumors and to estimate control intervals without irradiation in children with no residual tumor after initial surgery and induction chemotherapy and with delayed irradiation in patients with residual tumor or metastatic disease at diagnosis. PATIENTS AND METHODS: Patients were randomly assigned to one of two regimens of induction chemotherapy (vincristine, cisplatin, cyclophosphamide, and etoposide v vincristine, carboplatin, ifosfamide, and etoposide). Maintenance chemotherapy began after induction in children without progressive disease. Children with no residual tumors after induction therapy and no metastatic disease at diagnosis were not to receive radiation therapy unless their tumors progressed. RESULTS: Two hundred ninety-nine infants were enrolled. Forty-two percent of patients responded to induction chemotherapy. At 5 years from study entry, the EFS rate was 27% +/- 3%, and the survival rate was 43% +/- 3%. There was no significant difference between the two arms in terms of response rate or EFS. For medulloblastoma, supratentorial primitive neuroectodermal tumor, ependymoma, and rhabdoid tumors, 5-year EFS rates were 32% +/- 5%, 17% +/- 6%, and 32% +/- 6%, and 14% +/- 7%, respectively. Fifty-eight percent of patients who were alive 5 years after study entry had not received radiation therapy. CONCLUSION: Intensified induction chemotherapy resulted in a high response rate of malignant brain tumors in infants. Survival was comparable to that of previous studies, and most patients who survived did not receive radiation therapy.

Antineoplastic Combined Chemotherapy Protocols↗