Biomedical subjects

B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 145 records · Page 8Linked to original sources

PubMed1997

Randomized trial of radiation therapy (RT) plus dibromodulcitol (DBD) versus RT plus BCNU in high grade astrocytoma.

PURPOSE: We performed a randomized trial to compare survival distributions and toxicity of radiation therapy (RT) and DBD with RT and BCNU in patients with high-grade astrocytoma. METHODS: A total of 238 patients with supratentorial grade 3 and grade 4 astrocytoma were studied. Patients were stratified by age, extent of surgery, tumor grade, and performance score and randomly assigned to receive RT 55-60 Gy and either DBD, 200 mg/m2 orally on Days 1-10 every five weeks or BCNU, 200 mg/m2 intravenously every seven weeks. Median age was 60 years; 62% were 55 years or older. Eighty-three percent had subtotal resection, 58% had grade 4 tumors, and 83% had performance scores of 0-2. RESULTS: Survival distributions for all patients in the two arms were similar, with median survival of 41 weeks in each arm. Time to progression distributions were virtually identical, with medians of 22 weeks. BCNU produced significantly greater hematologic toxicity; median leukocyte and platelet nadirs on the first cycle were 3.6 vs. 4.7 (P = 0.0001) and 117 vs. 162 (P < 0.0001), and overall platelet nadirs were 80.5 vs. 114 (P = 0.0019). Non-hematologic toxicities were also significantly greater with BCNU, including nausea (57% vs. 31%; P < 0.0001) and vomiting (45% vs. 17%; P < 0.0001). CONCLUSION: This trial found no evidence of differences in treatment efficacy when either DBD or BCNU is combined with radiation therapy for patients with high-grade astrocytoma.

Algorithms↗

PubMed1997

Soft-tissue perineurioma. Evidence for an abnormality of chromosome 22, criteria for diagnosis, and review of the literature.

Reported herein are two examples of soft-tissue perineurioma (STP), one arising in the maxillary sinus and the other in subcutaneous tissue of the thigh. Electron microscopy and immunohistochemistry were performed in both cases. Based on our findings and a critical review of the literature, STPs are generally small, well-circumscribed but not encapsulated tumors. Histologically, most STPs resemble fibroblastic tumors, being composed of elongated, wavy cells. The immunohistochemical reactivity for epithelial membrane antigen, the lack of reactivity for S-100 protein, and the presence of ultrastructural features of perineurial cells are typical of this tumor. To explore the possibility that STP, like the intraneural variety of perineurioma, exhibits an abnormality of chromosome 22, we performed fluorescence in situ hybridization with a probe specific for the M-bcr locus, which maps to the chromosome band 22q11. In both our tumors, a high percentage of nuclei having only one M-bcr signal (44 and 96%) was observed. Our findings indicated deletion of part or all of chromosome 22 and support the view that both soft-tissue and intraneural perineurioma are part of a spectrum of perineurial neoplasia.

Chromosome Aberrations↗

PubMed1997

Salivary gland-like tumors of the sellar region.

Herein we present a group of rare tumors of the sella region that have not been previously recognized. Although clinically and radiographically the tumors resemble nonfunctioning pituitary adenomas, their histologic, immunohistochemical, and ultrastructural features differ and indicate a salivary gland origin. The lesions cover a morphologic spectrum that includes cellular pleomorphic adenoma, monomorphic adenoma, oncocytoma, and low-grade adenocarcinoma of the salivary gland. All tumors except the oncocytoma were immunoreactive for cytokeratin and were negative for pituitary hormones and synaptophysin. Ultrastructural characteristics in the cases examined include hypodense stromal material, basal lamina, and tonofilament bundles. The single oncocytoma was packed with mitochondria and lacked membrane-bound secretory granules. DNA ploidy based on image analysis and MIB-1 labeling indices showed diversity within this group of tumors, with labeling indices ranging from 0.06% to 15%. The presumed origin of these rare neoplasms is from salivary gland rests related to the normal pituitary gland. Despite their varied morphology, such tumors are easily confused with pituitary adenoma. Although rare, tumors of salivary gland origin should be considered in the differential diagnosis of unusual adenohypophyseal tumors.

Adenocarcinoma↗

PubMed1997

Composite pleomorphic xanthoastrocytoma and ganglioglioma: report of four cases and review of the literature.

Composite pleomorphic xanthoastrocytoma (PXA)-ganglioglioma (GG) is a rare recently described entity. Only three examples have been documented, one of which showed evidence of malignant transformation. We report an additional four cases and update the literature. With the exception of an 82-year-old man, all patients have been under 30 years of age. The temporal lobe was involved in three cases and cerebellum in another three. Radiologic features were those common to PXA and GG. Histologically, all were "collision tumors" composed of abutting, although spatially distinct, PXA and GG components. In two cases, the second element was only recognized at reexcision or recurrence. Histologic anaplasia, always in the PXA component, was evident as brisk mitotic activity and/or necrosis in five cases. Of the seven patients, one died of disease 17 years after the onset of seizures and after multiple recurrences, the last of which largely resembled glioblastoma. We conclude that the composite PXA-GG is a rare neoplasm that shares many features of its individual components. In addition to its temporal lobe predilection, the cerebellum is frequently affected. As when it occurs in isolation, the PXA component of composite PXA-GG possesses the potential for malignant transformation.

Adolescent↗

PubMed1997

Clear cell ependymoma: a mimic of oligodendroglioma: clinicopathologic and ultrastructural considerations.

Although clear cells resembling oligodendrocytes are known to occur in ependymomas, tumors composed primarily of such cells, i.e., clear cell ependymoma (CCE), are rare. Herein we characterize the clinicopathologic features of eight examples of CCE encountered at Mayo Clinic from 1983 to 1996. The tumors occurred in patients 3-31 years of age and presented as well-demarcated, deeply situated, contrast-enhancing masses, all of which were supratentorial. All but one case lacked classic light microscopic features of ependymoma. Although nearly all were immunoreactive for glial fibrillary acidic protein, it was electron microscopy that showed the diagnostic hallmarks of ependymoma, including complex intercellular junctions, surface microvilli and cilia, and microrosette formation, thus underscoring the importance of electron microscopy in the diagnosis of clear cell ependymomas. The differential diagnosis of CCE includes not only oligodendroglioma, but central neurocytoma and glioneurocytoma. Unlike oligodendrogliomas, CCEs are characterized by their sharp circumscription, hypervascularity as reflected in contrast enhancement on computed tomography and magnetic resonance imaging, their noninfiltrative pattern of growth that displaces parenchyma, and the occasional formation of vague perivascular pseudorosettes. Unlike central neurocytomas and glioneurocytomas, CCE lack secretory granules, vesicles, and synapses by electron microscopy and neuroendocrine markers by immunocytochemistry. In summary, the diagnosis of CCE requires neuroimaging, histologic, and ultrastructural correlation. The latter is essential in a limited biopsy. Ultrastructural studies also play a role in identifying glioneurocytomas. CCEs behave like more ordinary ependymomas. The importance of their recognition is the avoidance of alternative diagnoses and inappropriate therapies.

Adolescent↗

PubMed1997

The immunophenotypic spectrum of meningeal hemangiopericytoma: a comparison with fibrous meningioma and solitary fibrous tumor of meninges.

Despite controversy regarding its histogenesis, meningeal hemangiopericytoma (HPC) is a well-defined clinicopathologic entity exhibiting high rates of recurrence and late extracranial metastasis. It must be distinguished from several benign neoplasms, particularly fibrous meningioma (FM) and solitary fibrous tumor (SFT). To determine the immunoprofile of HPC, we studied 27 meningeal examples, including 13 low-grade and 14 high-grade tumors. For comparison, 20 FMs and eight SFTs of the meninges were also evaluated. The immunotype of HPC included vimentin (85%), factor XIIIa (78%) in individual scattered cells, Leu-7 (70%), and CD34 (33%) in a weak, patchy pattern. Focal desmin and cytokeratin positivity was only occasionally encountered (20% each). The SFT shared a similar immunophenotype, except that CD34 expression (100%) was characteristically strong and diffuse. The FM characteristically expressed epithelial membrane antibody (EMA) (80%) and S-100 protein (80%); CD34 reactivity (60%) was patchy and weak. Both within and among all three tumor types, MIB-1 labeling indices varied widely. Specifically, they were unrelated to tumor grade in HPC. Significant reactivity for p53 protein was detected in 52% of HPCs, 17% of SFTs, and 5% of FMs. Meningeal HPC exhibits a distinct antigenic profile, one enabling the exclusion of other entities in nearly all cases. The rare expression of desmin or cytokeratin in HPC suggests either the occurrence of divergent differentiation or, less likely, the possibility that its distinctive morphology is but a phenotype shared by several types of meningeal sarcoma.

Adult↗

PubMed1997

Meningioma grading: an analysis of histologic parameters.

Histologic grading of meningiomas has prognostic and sometimes therapeutic implications, but diagnostic criteria for atypical meningioma are vague, and the significance of brain invasion in the determination of malignancy remains controversial. We reviewed our experience with 581 patients whose meningiomas were resected at Mayo Clinic during the years 1978 through 1988. All patients were followed until death or a median of 9.0 years. Ten histologic parameters were assessed and compared with recurrence-free survival. On univariate analysis, six variables were associated with recurrence, although most were statistically significant only in the subset of patients having undergone gross total tumor resection. On multivariate analyses, the most significant parameters were histologic brain invasion (when assessable) and maximal mitotic rate of at least four per 10 high-power fields (HPF). Also significant were combinations of at least three of the following four parameters: hypercellularity, architectural sheeting, macronucleoli, and small cell formation. Proposed grading criteria based on these findings yielded 81% classic, 15% atypical, and 4% brain invasive meningiomas with respective 5-year recurrence rates of 12%, 41%, and 56%. There was no association between histologic grade and either extent of surgical resection or patient age. However, male sex was associated with high-grade (atypical/brain invasive) tumors. Too few frankly anaplastic meningiomas were encountered for statistical analysis. Brain invasion and an increased mitotic index (at least four per 10 HPF) are the most powerful histologic factors prognostic for recurrence in meningiomas. We propose an objective definition for atypical meningioma based on our data. Because the difference in recurrence rates for brain invasive and atypical meningiomas was not statistically significant, it could not be determined whether brain invasion alone warrants a designation of malignancy. Likewise, we were unable to determine what constitutes histologic anaplasia due to the rarity of such cases.

Analysis of Variance↗

PubMed1997

Atypical central neurocytoma.

The proliferative potential of central neurocytomas was determined in a biopsy series of 36 cases and compared with clinical outcome. The mean size of the growth fraction, as determined by MIB-1 labeling index (MIB-1 LI) at first biopsy, was 2.8 +/- 2.5 with a range of 0.1 to 8.6%. Neurocytomas with an MIB-1 LI > 2% comprised 39% of cases and showed a close correlation with the presence of vascular proliferation (p = 0.0006). The Kaplan-Meier analysis showed a highly significant difference in disease-free survival between the 2 groups (p = 0.0068). Over an observation time of 150 months, there was a 22% relapse among patients with an MIB-1 LI less than 2% and a 63% chance of relapse among those with an MIB-1 LI greater than 2%. We propose the term "atypical central neurocytoma" for the latter subset, corresponding to WHO grade II.

Adolescent↗

PubMed1997

Oestrogen receptors in meningiomas: a correlative PET and immunohistochemical study.

There have been a number of indications that sex hormones can affect the rate of growth of meningiomas during pregnancy. The presence of oestrogen or progesterone receptors in meningiomas and the influence of sex hormones upon cell cultures derived from human meningiomas have been extensively investigated. The results have been controversial, with most of the discussion centring upon the presence and possible role of oestrogen receptors. The aim of the present study was to assess oestrogen receptors in human meningiomas with 16alpha[l8F]fluoro-17beta-oestradiol ([18F]FES) and positron emission tomography (PET). With this purpose in mind, we measured the regional brain uptake of [18F]FES in six patients with a neuroradiological and histological diagnosis of meningioma, comparing the in vivo PET data with the immunohistological analysis of oestrogen receptors performed on formalin-fixed, paraffin-embedded tissue obtained at surgery. Two analyses were used for the in vivo measurement of [18F]FES binding to oestrogen receptors: the ratio of tumour activity to that of normal tissue (T/NT), calculated 90 min after tracer injection, and the ratio between the equilibrium distribution volume (DV) in normal and pathological tissues, calculated by means of a graphical kinetic analysis. PET studies demonstrated a marked uptake of [18F]FES by the tumour in four of the six patients. Immunohistochemical assay using a manual staining method capable of detecting oestrogen receptors at a level of > 10 pmol mg(-1) of protein detected only sparse immunostaining in one of the six meningiomas. Distinct albeit weak immunostaining was demonstrated in five of the six meningiomas when the sensitivity of the immunohistochemical assay was increased to < 10 pmol mg(-1) of protein by use of an automated staining method (Bioteck 1000). Comparison of the in vivo and immunohistochemical results showed a correlation in five of the six patients, thus indicating the high sensitivity of [18F]FES for the in vivo evaluation of oestrogen receptor expression.

Adult↗

PubMed1997

Classification and grading of low-grade astrocytic tumors in children.

This article reviews current perspectives in the classification and grading of astrocytomas in children and calls attention to several histologically distinct groups of low-grade tumors that characteristically arise during childhood. Recognition of these tumors and the range of histological features that they may exhibit is essential for making rational assessments regarding their expected behavior and, more importantly, for guiding therapeutic intervention. For example, pleomorphic xanthoastrocytoma, which may exhibit "anaplastic" features, generally carries a relatively favorable prognosis and should not be classified with other high-grade gliomas, such as anaplastic astrocytoma and glioblastoma multiforme. Similarly, the finding of anaplastic features, such as vascular proliferation or necrosis, in pilocytic astrocytomas does not automatically portend the unfavorable prognosis that such features would imply for "diffuse" astrocytomas. Increased appreciation of the morphological diversity of astrocytomas in children should help to improve the management of children with low-grade astrocytic tumors by avoiding potentially dangerous overtreatment of otherwise indolent lesions.

Astrocytoma↗

PubMed1997

Effective chemotherapy for advanced CNS embryonal tumors in adults.

PURPOSE: Embryonal tumors of the CNS include, among others, medulloblastoma, cerebral neuroblastoma, pineoblastoma, and primitive neuroectodermal tumors (PNETs). Almost all data on the treatment of embryonal CNS tumors are derived from the pediatric population, since these tumors are uncommon in adulthood. The purpose of this study was to examine the rate and duration of response to chemotherapy of advanced embryonal CNS tumors in adults. PATIENTS AND METHODS: We retrospectively studied all adult (> 18 years of age) patients with advanced embryonal tumors of the CNS who received chemotherapy at our institution between 1976 and 1994. Seventeen consecutive patients were treated with regimens that contained either nitrosourea or cisplatin or both sequentially, with no patients having received the combination of nitrosourea and cisplatin concurrently. RESULTS: In patients who received cisplatin-based chemotherapy, responses were observed in 84.5% (26% complete response [CR] rate), 10.5% remained stable, and 5% progressed. The median time to progression was 18 months for patients who had a CR, 6 months for those with partial response (PR), and 10 months for stable patients. Among patients who received nitrosourea-based chemotherapy, PR was observed in 27%, 36.5% remained stable, and 36.5% progress. The median time to progression was 6 months for patients who had a PR and 6.5 months for stable patients. CONCLUSION: In adults with advanced embryonal CNS tumors, conventional-dose intravenous cisplatin-based chemotherapy regimens are able to produce responses in the majority of the patients (84.5%), even as second- or third-line regimens. Nitrosourea-based regimens less frequently produce responses (27%).

Adolescent↗

PubMed1997

Prolactin receptor messenger ribonucleic acid in normal and neoplastic human pituitary tissues.

We examined the specific cell types in normal human pituitaries that expressed PRL receptor (PRL-R) messenger ribonucleic acid (mRNA) by combined in situ hybridization and immunohistochemistry. The distribution of PRL-R mRNA in 28 pituitary adenomas was examined by in situ hybridization and reverse transcription-PCR in 12 cases of adenomas. In another set of experiments, 34 PRL adenomas from men, women, and bromocriptine-treated patients were analyzed for PRL-R by in situ hybridization. In the normal pituitary, PRL- and LH-producing cells had significantly more mean grain counts per cell and higher percentages of cells positive for PRL-R than GH and TSH cells. PRL-R mRNA was present in all groups of adenomas by in situ hybridization and reverse transcription-PCR. PRL adenomas had a significantly higher density of labeling compared to other adenoma types. Although there was no difference in the levels of PRL-R mRNA in PRL adenomas from men and premenopausal and postmenopausal women, patients treated with bromocriptine before pituitary surgery had significantly lower levels of PRL-R compared to all other groups. These results indicate that in the normal pituitary, PRL and LH cells have the highest level of PRL-R mRNA, whereas PRL adenomas have significantly higher levels of PRL-R mRNA than other types of adenomas, and bromocriptine treatment decreases the levels of PRL-R mRNA in PRL adenomas.

Adenoma↗

PubMed1997

Gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor messenger ribonucleic acids expression in nontumorous and neoplastic pituitaries.

In the nontumorous pituitary, GnRH stimulates the release and synthesis of LH and FSH by gonadotroph cells via the GnRH receptor (GnRH-R). Little is known, however, about expression of GnRH and GnRH-R messenger RNAs (mRNAs) in nontumorous pituitary tissue and in adenomas. To learn more about the distribution and regulatory roles of GnRH and its receptor, we investigated the expression of both GnRH and GnRH-R mRNAs in nontumorous human pituitary and in various types of pituitary adenomas using the RT-PCR, in situ hybridization, and in situ hybridization in combination with RT-PCR (in situ RT-PCR). Using RT-PCR, GnRH mRNA was found to be expressed in normal human pituitaries and in all types of adenomas. Similarly, GnRH-R mRNA was expressed in nontumorous human pituitaries and in most, but not all, adenomas. These included 5 gonadotroph adenomas, 6 null cell adenomas, 1 of 2 GH-producing tumors, and 1 of 2 ACTH-producing adenomas, but not in the 2 PRL-producing adenomas examined. In situ hybridization studies showed GnRH and GnRH-R mRNAs in all 3 nontumorous pituitaries and in 12 of 33 (36.4%) and 10 of 33 adenomas (30.3%), respectively. Using an indirect in situ RT-PCR technique to increase the sensitivity of the in situ localization, GnRH and GnRH-R mRNAs were detected in 29 (87.9%) and 25 (75.8%) of 33 adenomas, respectively. This is the first report of the localization of GnRH and GnRH-R mRNAs in individual pituitary adenoma cells using in situ RT-PCR. The frequent expression of GnRH and GnRH-R mRNAs in pituitary cells suggests that GnRH has autocrine/paracrine functions in nontumorous and neoplastic pituitary tissues.

Gonadotropin-Releasing Hormone↗

PubMed1997

Analysis of proliferation markers and p53 expression in gliomas of astrocytic origin: relationships and prognostic value.

Consecutive paraffin sections of 105 astrocytomas and 15 oligoastrocytomas were examined for expression of p53, MIB-1 (Ki-67), and proliferating cell nuclear antigen (PCNA). The tumors had been examined previously for genetic abnormalities and by flow cytometry. Regardless of the tumor's stage and grade and the patient's age and gender, p53 expression was found in 40% of tumors. Although p53 expression was associated with a loss on chromosome 17p and was more frequent in aneuploid tumors, it had no association with survival time. The MIB-1 and PCNA labeling indices increased with increasing tumor grade but showed no association with other clinicopathological parameters. In individual tumors, there was poor concordance between any of the variables (MIB-1, PCNA, and p53). Results for p53 and MIB-1 were similar for both astrocytomas and oligoastrocytomas. The MIB-1 and PCNA values appeared to have prognostic utility in univariate analysis but not after adjusting for patient age and tumor grade. The poor concordance between MIB-1 and PCNA in individual tumors indicates that any one means of assessing proliferative potential in gliomas may not be reliable.

Adolescent↗

PubMed1997

Transforming growth factor-beta, transforming growth factor-beta receptor II, and p27Kip1 expression in nontumorous and neoplastic human pituitaries.

Transforming growth factor (TGF)-beta has been implicated in the regulation of normal and neoplastic anterior pituitary cell function. TGF-beta regulates the expression of various proteins, including p27Kip1 (p27), a cell cycle inhibitory protein. We examined TGF-beta, TGF-beta type II receptor (TGF-beta-RII), and p27 expression in normal pituitaries, pituitary adenomas, and carcinomas to analyze the possible roles of these proteins in pituitary tumorigenesis. Normal pituitary, pituitary adenomas, and pituitary carcinomas all expressed TGF-beta and TGF-beta-RII immunoreactivity. Reverse transcription polymerase chain reaction analysis showed TGF-beta 1, -beta 2, and -beta 3 isoforms and TGF-beta-RII in normal pituitaries and pituitary adenomas. Pituitary adenomas cells cultured for 7 days in defined media showed a biphasic response to TGF-beta with significant inhibition of follicle-stimulating hormone secretion at higher concentrations (10(-9) mol/L) and stimulation of follicle-stimulating hormone secretion at lower concentrations (10(-13) mol/L) of TGF-beta 1 in gonadotroph adenomas. Immunohistochemical analysis for p27 protein expression showed the highest levels in nontumorous pituitaries with decreased immunoreactivity in adenomas and carcinomas. When nontumorous pituitaries and various adenomas were analyzed for p27 and specific hormone production, growth hormone, luteinizing hormone, and thyroid-stimulating hormone cells and tumors had the highest percentages of cells expressing p27, whereas adrenocorticotrophic hormone cells and tumors had the lowest percentages. Immunoblotting analysis showed that adrenocorticotrophic hormone adenomas also had the lowest levels of p27 protein. Semiquantitative reverse transcription polymerase chain reaction and Northern hybridization analysis did not show significant differences in p27 mRNA expression in the various types of adenomas or in nontumorous pituitaries. In situ hybridization for p27 mRNA showed similar distributions of the gene product in nontumorous pituitaries, pituitary adenomas, and carcinomas. These results indicate that TGF-beta and TGF-beta-RII are widely expressed in nontumorous pituitaries and in pituitary neoplasms and that TGF-beta 1 regulates pituitary hormone secretion. The levels of the TGF-beta-regulated protein p27 decreases in the progression of normal to neoplastic pituitaries. In contrast, the mRNA levels of p27 remained relatively constant in nontumorous pituitaries, pituitary adenomas, and carcinomas, indicating that p27 protein levels in adenomas and carcinomas are regulated by translational and post-translational mechanisms.

Adenoma↗

PubMed1997

Giant plexiform schwannoma: a report of two cases with soft tissue and visceral involvement.

We report two cases of massive, solitary, plexiform schwannoma. One was a 9-cm subcutaneous lesion on the hip of a 72-year-old man who had become aware of the slow-growing tumor 50 years earlier; the other is the first reported plexiform schwannoma to arise in a visceral organ: it arose in the ascending colon of a 54-year-old man and exhibited a dumbbell configuration with submucosal and subserosal components. Neither patient had neurofibromatosis or schwannomatosis. Both tumors were well-circumscribed and multinodular, and both showed a plexiform architecture. Microscopically, the nodules were composed primarily of Antoni A tissue, replete with nuclear palisading and Verocay bodies. Examination by immunohistochemistry and electron microscopy demonstrated the features of well-differentiated Schwann cells; nodules were surrounded by attenuated, residual perineurium. Both patients followed a benign clinical course, without recurrence or metastasis. Neither the large tumor size nor the unusual locations affected the biologic behavior of these neoplasms. A massive plexiform schwannoma must be distinguished from a malignant peripheral nerve sheath tumor and from a plexiform neurofibroma, a tumor prone to malignant transformation.

Aged↗

PubMed1997

Loss of tuberin in both subependymal giant cell astrocytomas and angiomyolipomas supports a two-hit model for the pathogenesis of tuberous sclerosis tumors.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by seizures, mental retardation, and tumors of skin, brain, heart, and kidney. In this study, we focused on two of the most frequent tumors in TSC patients, renal angiomyolipomas and subependymal giant cell astrocytomas (SEGAs). Two questions were addressed. First, is loss of tuberin, the product of the TSC2 gene, seen in both renal and central nervous system tumors from TSC patients? Second, when loss of tuberin occurs, does it affect each of the cell types seen in these tumors? We used a loss of heterozygosity approach to identify tumors from TSC2 patients. We found loss of tuberin immunostaining in the spindle and epithelioid cells but not in the giant cells of six TSC2 SEGAs. We also found loss of tuberin immunostaining in all three cell types (smooth muscle, fat, and vessels) of six TSC2 angiomyolipomas. Chromosome 16p13 loss of heterozygosity occurred in both spindle and epithelioid cells of a SEGA and in smooth muscle and fat but not the vessels of two angiomyolipomas. These results support a two-hit tumor suppressor model for the pathogenesis of SEGAs and angiomyolipomas. The vascular elements of angiomyolipomas and the giant cells of SEGAs may be reactive rather than neoplastic.

Angiomyolipoma↗

PubMed1996

Histologically confirmed pineal tumors and other germ cell tumors of the brain.

BACKGROUND: This study examined the outcome of patients with histologically confirmed pineal region tumors. METHODS: One hundred thirty-five patients with histologically confirmed pineal tumors and other germ cell tumors of the brain were evaluated retrospectively. The pineal parenchymal tumors (PPTs) included 15 pineoblastomas (PB), 2 mixed PPTs, 4 PPTs with intermediate differentiation, and 9 pineocytomas. The germ cell tumors included 48 germinomas, 26 mixed germ cell tumors, 11 mature teratomas, 9 immature teratomas, 6 malignant teratomas, 2 yolk sac tumors, and 3 choriocarcinomas. Patients were treated with various combinations of chemotherapy, radiotherapy, and surgery. The duration of follow-up ranged from 0.25 to 37.3 years, with a median follow-up of 5.3 years. RESULTS: The 5-year patient survival rate was 86% for those with mature teratomas; 86% with pineocytomas; 80% with germinomas; 67% with immature teratomas; 49% with PPTs, excluding pineocytomas; 38% with mixed germ cell tumors; and 17% with other germ cell histologies (P = 0.0001). The delivery of > 44 Gray (Gy) to germinomas and > 50 Gy to PPTs and nongerminomatous germ cell tumors (NGGCTs) other than mature and immature teratomas was associated with improved survival. A greater extent of resection was associated with a higher rate of survival in all patients with NGGCTs. The administration of chemotherapy was associated with improved survival in those patients with NGGCTs other than mature and immature teratomas. CONCLUSIONS: Prognosis was dependent on tumor type. Obtaining a tissue diagnosis made it possible to tailor therapy according to tumor type and potentially improve the survival of patients. Survival was dependent on the dose of radiation administered to patients with PPTs, germinomas, and NGGCTs other than mature and immature teratomas. More extensive resection and the use of chemotherapy were also associated with improved survival in subgroups of patients with NGGCTs. Treatment recommendations are described in detail in the article.

Adolescent↗