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At least 199 records · Page 11Linked to original sources
PubMed2004

Gene expression in the bladder carcinoma rat model.

We investigated gene expression in N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced rat bladder carcinoma in order to test its applicability as a model for the study of novel therapeutic modalities, particularly gene therapy. We administered BBN in the drinking water to Wistar rats for up to 30 wk and induced papillary transitional cell carcinoma (TCC), which is similar to the most prevalent type of human bladder cancer. Tumor evolution was similar to that found in previous studies. However, we described the morphological stages according to modern human bladder carcinoma terminology. Our main goal was to examine the expression levels of the H19 gene, of the insulin-like growth factor 2 (Igf2) transcripts expressed from promoters P2 and P3 and of the telomerase subunits that we had previously investigated as tools for targeted gene therapy of bladder cancer. We detected at 30 wk of BBN exposure significant upregulation of these sequences in the rat bladder tumors, similar to our previous findings in human bladder cancer. To reinforce the similarity of this model to the corresponding human disease, we searched for additional tumor-specific genes documented as having altered expression in human bladder carcinoma, using cDNA expression arrays (Clontech). We suggest that BBN-induced rat bladder cancer has morphological, biological, and molecular parallels to human bladder cancer and is an attractive model for studying novel alternatives of therapeutic intervention.

Animals↗
PubMed2025

Defining the genome-wide mutagenic impact of APOBEC3 enzymes.

Somatic mutations drive cancer initiation and tumor evolution. Therefore, the etiology of mutagenesis in cancer is important to preventative and treatment strategies. Somatic mutagenesis in cancer is a multifactorial process and includes both endogenous and exogenous sources of mutations. One recently recognized source of mutagenesis in cancer is the innate immune APOBEC3 family of enzymes, which catalyze cytosine deamination to restrict viral infection but can aberrantly act on the cellular genome, resulting in mutations. Single base substitution (SBS) signatures, or mutational patterns, identified in cancer genomes have demonstrated widespread mutagenesis caused by APOBEC3 enzymes throughout human tumors. To comprehensively define the consequences of APOBEC3 mutagenesis, we developed an experimental pipeline for prospective analysis of genome-wide mutations caused by APOBEC3 activity. This pipeline can be adapted to analyze additional sources of mutagenesis across a spectrum of cells.

Humans↗
PubMed2025

CINner: Modeling and simulation of chromosomal instability in cancer at single-cell resolution.

Cancer development is characterized by chromosomal instability, manifesting in frequent occurrences of different genomic alteration mechanisms ranging in extent and impact. Mathematical modeling can help evaluate the role of each mutational process during tumor progression, however existing frameworks can only capture certain aspects of chromosomal instability (CIN). We present CINner, a mathematical framework for modeling genomic diversity and selection during tumor evolution. The main advantage of CINner is its flexibility to incorporate many genomic events that directly impact cellular fitness, from driver gene mutations to copy number alterations (CNAs), including focal amplifications and deletions, missegregations and whole-genome duplication (WGD). We apply CINner to find chromosome-arm selection parameters that drive tumorigenesis in the absence of WGD in chromosomally stable cancer types from the Pan-Cancer Analysis of Whole Genomes (PCAWG, [Formula: see text]). We found that the selection parameters predict WGD prevalence among different chromosomally unstable tumors, hinting that the selective advantage of WGD cells hinges on their tolerance for aneuploidy and escape from nullisomy. Analysis of inference results using CINner across cancer types in The Cancer Genome Atlas ([Formula: see text]) further reveals that the inferred selection parameters reflect the bias between tumor suppressor genes and oncogenes on specific genomic regions. Direct application of CINner to model the WGD proportion and fraction of genome altered (FGA) in PCAWG uncovers the increase in CNA probabilities associated with WGD in each cancer type. CINner can also be utilized to study chromosomally stable cancer types, by applying a selection model based on driver gene mutations and focal amplifications or deletions (chronic lymphocytic leukemia in PCAWG, [Formula: see text]). Finally, we used CINner to analyze the impact of CNA probabilities, chromosome selection parameters, tumor growth dynamics and population size on cancer fitness and heterogeneity. We expect that CINner will provide a powerful modeling tool for the oncology community to quantify the impact of newly uncovered genomic alteration mechanisms on shaping tumor progression and adaptation.

Chromosomal Instability↗
PubMed1994

Thymic carcinoma with a defective Epstein-Barr virus encoding the BZLF1 trans-activator.

The diagnosis of Epstein-Barr virus (EBV)-associated carcinomas is often heralded by high antibody titers to the viral replicative antigens, suggesting EBV reactivation may be a factor in tumor evolution. EBV DNA and nuclear antigen was detected in a newly diagnosed thymic carcinoma. Polymerase chain reaction analysis revealed the presence of a rearranged EBV DNA fragment, BamHI WZhet. This rearrangement is found in a defective EBV that up-regulates the BZLF1 (BamHI Z leftward reading frame) gene product in vitro and induces the EBV lytic cycle. Molecular analysis of the EBV termini demonstrated low levels of the lytic (linear) genomic configuration among a predominantly latent (episomal) population at diagnosis. The episomal populations were of uniform molecular weight at diagnosis and relapse, indicating clonal tumor expansion from a single EBV-infected progenitor. The presence within malignant epithelium of defective virus that can disrupt EBV latency, and perhaps cellular gene regulation, suggests a potential mechanism for EBV reactivation and concurrent malignant progression.

Adolescent↗
PubMed2000

A physical-based model for the simulation of neoplastic growth and metastasis.

BACKGROUND AND OBJECTIVES: It is possible to formulate models capable of reproducing the main details of the physical processes involved in the evolution of biological systems. The complexity of the problem requires to begin with a simple and universal model for the description of the cellular growth, to be adapted successively to the local conditions found in clinically observed neoplastic growths. METHODS: A model based on the Local Interaction Simulation Approach (LISA) has been formulated for the simulation of growth, diffusion, and metastasis of neoplasms. The vascularization is described by a blood vessel located on one edge of the specimen in which a constant and homogeneous flow is assumed. A nutrient density is defined to mimic the blood flow within the tissue. RESULTS: Photograms taken at proper times may identify the main characteristics of the tumor evolution and describe its volume variations in a transversal section. Furthermore, it is possible to monitor constantly the volume of the neoplasm and of the necrotic tissue as a function of time, as well as the portion of cells that have migrated in the blood vessel. CONCLUSIONS: In spite of strong simplifying assumptions, the model presents good qualitative agreement with clinical data, which may be further improved by more detailed information about cancer cells properties or local vascular system patterns.

Animals↗
PubMed2005

PIK3CA mutations correlate with hormone receptors, node metastasis, and ERBB2, and are mutually exclusive with PTEN loss in human breast carcinoma.

Deregulation of the phosphatidylinositol 3-kinase (PI3K) pathway either through loss of PTEN or mutation of the catalytic subunit alpha of PI3K (PIK3CA) occurs frequently in human cancer. We identified PIK3CA mutations in 26% of 342 human breast tumor samples and cell lines at about equal frequency in tumor stages I to IV. To investigate the relationship between PTEN and PIK3CA, we generated a cohort of tumors that had lost PTEN expression and compared it with a matched control set that had retained PTEN. A highly significant association between PIK3CA mutations and retention of PTEN protein expression was observed. In addition, PIK3CA mutations were associated with expression of estrogen and progesterone receptors (ER/PR), lymph node metastasis, and ERBB2 overexpression. The fact that PIK3CA mutations and PTEN loss are nearly mutually exclusive implies that deregulated phosphatidylinositol-3,4,5-triphosphate (PIP(3)) is critical for tumorigenesis in a significant fraction of breast cancers and that loss of PIP(3) homeostasis by abrogation of either PIK3CA or PTEN relieves selective pressure for targeting of the other gene. The correlation of PIK3CA mutation to ER/PR-positive tumors and PTEN loss to ER/PR-negative tumors argues for disparate branches of tumor evolution. Furthermore, the association between ERBB2 overexpression and PIK3CA mutation implies that more than one input activating the PI3K/AKT pathway may be required to overcome intact PTEN. Thus, mutation of PIK3CA is frequent, occurs early in carcinoma development, and has prognostic and therapeutic implications.

Adult↗
PubMed1997

Potential biomarkers in predicting progression of epithelial hyperplastic lesions of the larynx.

Factors contributing to malignant transformation of laryngeal pre-neoplastic lesions remain largely unknown. Potential etiologic factors may be related to a genetically controlled sensitivity to environmental carcinogens. In this study, we investigated bleomycin-induced chromosome fragility in 15 patients with laryngeal keratoses who experienced a malignant transformation of pre-neoplastic lesions during follow-up, as compared with chromosome fragility in 15 historical controls with no progression of laryngeal keratoses during a 10-year follow-up, in a match-paired analysis. Chromosomal analysis demonstrated a higher sensitivity to clastogens in patients with malignant progression of laryngeal pre-neoplastic lesions than that of control patients with no evolution of their original laryngeal keratoses (p < 0.01). Furthermore, in the attempt to identify possible prognostic markers we studied proliferative activity (MIB-1 expression) and p53 gene aberration in biopsy samples from non-invasive and invasive laryngeal lesions in both groups. p53 immunostaining was observed in 10/15 (66.7%) of pre-neoplastic lesions and in 11/15 (73.3%) of metachronous laryngeal cancers. No differences in terms of p53 expression were noted between transformed and not-transformed lesions. Mutations at p53 gene were observed in 3/15 (20%) of pre-invasive biopsies and in 4/5 (80%) of the laryngeal cancers analyzed. Our data suggest that p53 alteration is an early event in the genesis of a subset of laryngeal carcinomas and that there is no conclusive data about the possible clonal development of metachronous laryngeal carcinoma from a p53 mutated pre-invasive disease in the same patient. MIB-1 expression was found to progressively increase with degree of epithelial hyperplasia and dysplasia in both transformed (p = 0.007) and not-transformed (p < 0.1) lesions. Surprisingly, pre-invasive lesions with tumor evolution showed a lower proliferative activity when compared with laryngeal lesions without malignant transformation (p = 0.013). These data suggests that subjects with pre-neoplastic laryngeal lesion showing an increased susceptibility to carcinogens and with less proliferative disease could be at a higher risk for development of laryngeal carcinoma.

Antigens, Nuclear↗
PubMedDate not supplied

How should PCNA be assessed? Total of stained cells or only the most intensely stained ones?

OBJECTIVE: This study aimed to analyse whether a marker of proliferative activity (PCNA) could provide a prognosis of tumor evolution and to determine whether different interpretation criteria could alter the results. METHOD: The presence of PCNA in 59 patients of state II (T2 N0.1 M0) mammary carcinoma was determined. RESULT: Numerical proportions of total and intensely stained cells were established. These data were compared with anatomopathological parameters. A significant association between higher cyclin values and worse histological and nuclear grading was encountered, particularly in patients with a "negative axilla" using the PCNA index. Cyclin values were not significant in relation to any parameters when indices from the intensely stained cells were considered exclusively. CONCLUSION: Higher nuclear (NG3) and histological (HGIII) grading, associated with a high PCNA index (> 50), distinguish high-risk patients, and it is more appropriate considering all the stained cells as representative of PCNA indices, thus reflecting tumor aggressiveness.

Breast Neoplasms↗
PubMed2026

MET Exon 14 Skipping Mutation in NSCLC: From Genomic Discovery to Biomarker-Guided Therapeutic Innovation.

INTRODUCTION: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, and the MET exon 14 skipping mutation is a key oncogenic driver, which promotes tumor progression and provides a new direction for precision therapy. METHODS: A systematic search of English-language literature and clinical trial data related to the MET exon 14 skipping mutation from 2020-2025 was performed to summarize the role of the mutation and therapeutic advances. RESULTS: DNA-based next-generation sequencing (NGS), RNA-based NGS, and RT-qPCR were employed as the main detection methods. Preclinical models confirmed that mutations promote tumor progression by activating the RAS/MAPK pathway. Clinical trials have reported objective remission rates (ORR) of 46-68% for first-line treatment with MET inhibitors in NSCLC patients harboring MET exon 14 skipping mutations. DISCUSSION: MET exon 14 skipping mutation as a therapeutic target for NSCLC has made significant progress, and MET inhibitors are more advantageous than chemotherapy and immunotherapy, and have been recommended by national and international guidelines as a first-line treatment option. Additionally, NGS technology has the potential to dynamically monitor tumor evolution and drugresistant mutations, thereby helping to realize precision medicine. CONCLUSION: The MET exon 14 skipping mutation is an important target for the precision treatment of NSCLC, and MET-TKIs have remarkable efficacy but a prominent problem with drug resistance. The construction of a precision medicine system encompassing diagnosis, treatment, and drug resistance management through multi-omics research, technological innovation, and international collaboration is a key direction for improving prognosis.

Humans↗
PubMed1977

[Evolution of hepatocyte population in the process of chemical carcinogenesis].

By means of two different markers of differentiation, using immunofluorescene method, the authors have characterized changes in the population of hepatic cells 1-8 weeks following the start of 3'-methyl-4-dimethyl-aminoazobenzene or 2-acetyl-aminofluorene action. Alpha-fetoprotein served as a marker of embryonic hepatocyte differentiation; while ligandin-as a marker of high-differentiated mature hepatocytes. The toxic effect of the carcinogens on hepatic stem cells was accompanied with a decrease of ligandin content in centrilobular hepatocytes. Among newly proliferating elements "oval" cells, cells of bile tract epithelium and most of basophilic hepatocyte-like cells fail to contain either alpha-fetoprotein or ligandin. Small groups of basophilic hepatocyte-like cells would contein alpha-fetoprotein. In cells of high cylinder-shaped epithelium of intestinal type ligandin was found, but alpha-fetoprotein was not found. The latter was absent in oxyphilous hepatocytes of hyperplastic nodules. In terms of ligandin content three types of morphologically identical nodules were differentiated; a) ones not containing this protein, b) ones containing it in amounts common to normal mature hepatocyte, and c) hyperdifferentiated nodules containing abnormally high concentrations of ligandin. Within one nodule cell all cells were identical in ligandin content. Thus, it is shown that at early stages of chemical carcinogenesis there occure in the liver multiple foci of differentiation of various kind. These intensive processes are assumed to be essential for tumor evolution in the tissue.

2-Acetylaminofluorene↗
PubMed1991

Cytogenetic analysis of 434 consecutively ascertained specimens of non-Hodgkin's lymphoma: correlations between recurrent aberrations, histology, and exposure to cytotoxic treatment.

Cytogenetic abnormalities in non-Hodgkin's Lymphoma (NHL) provide a model system for the analysis of the role of multiple genomic aberrations in human malignancy. In order to define correlations with histology, tumor evolution, and the effects of genotoxic exposure, cytogenetic analysis was performed on 434 specimens of NHL derived from 423 patients consecutively ascertained over a 5-year period (1984-1989). Six recurring translocations (RT) were observed: t(14;18)(q32;q21), t(8;14)(q24;q32), t(11;14)(q13;q32), t(3;22)(q27;11), t(2;5)(p23;q35), and t(1;6)(q21;q25). No translocation was specific to a single histologic subtype. Other structural chromosome abnormalities were analyzed according to break site; groups of related breaks were considered together for statistical analysis. Recurring other structural and numerical aberrations (ROA) encountered in greater than 10% of specimens included rearrangements with breaks at bands 1p32-36, 1q21-23, 6q21-25, and trisomies of chromosomes 7 and 12. ROA with one of these breaks or numerical abnormalities were the sole abnormalities in at least two cases. Correlations were observed among ROA and between ROA and histologic subtypes. Trisomy 7, breaks at 1q21-23, 1p32-36, 6q21-25, and 7q32 were associated with t(14;18); trisomy 18 was associated with trisomy 3; and structural abnormalities of chromosome 17 were associated with breaks at 1p32-36 and 6q21-25. Trisomy 7 and trisomy 12 were more frequent in t(14;18)-bearing intermediate to high grade tumors compared to low grade tumors. Trisomy 12 and breaks at band 1p22 were associated with large cell diffuse lymphomas. Incidence rates of reciprocal translocations, ROA, and measures of karyotypic complexity, including number of breakpoints and marker chromosomes were compared in pretreatment and posttreatment samples. Karyotypic complexity was greater in the posttreatment samples, reflecting an increased frequency of nonrecurring and low incidence aberrations. These results better define the association of genomic aberrations and tumorigenesis, histologic transformation, and tumor progression.

Alkylating Agents↗
PubMed1997

Lymphokine-activated killer (LAK)-mediated lysis of sequentially isolated ovarian cancer cell lines.

PROBLEM: Understanding immunologic eradication of cancer is hampered by failure to explore tumor evolution. Cell surface molecules may alter with therapy and disease progression. These alterations can translate into variable susceptibility to immune-mediated cell lysis. METHOD OF STUDY: Cell lines from a patient with ovarian carcinoma isolated at surgical debulking (UL-3A), during chemotherapy (UL-3B), and after progression (UL-3C) were used to study changes in cell lysis by natural killer (NK) and lymphokine-activated killer (LAK) cells. The role of adhesion molecules ICAM-1, LFA-3, and glycoproteins in the demonstrated differential killing was also examined. RESULTS: An inverse relationship between attachment and lysis was demonstrated. UL-3C, the most sensitive to lysis (50%), attached the least lymphocytes (40%), whereas UL-3A, the least sensitive (33%), attached the most lymphocytes (71%). A correlation with ICAM-1 and LFA-3 expression was not demonstrated. CONCLUSION: Ovarian cancer cells evolve throughout the disease course, and this may manifest as differential sensitivity to immune-mediated cell lysis.

Cytotoxicity, Immunologic↗
PubMed2026

Non-coding RNAs as regulators of chromosomal instability in breast cancer.

Breast cancer is a highly heterogeneous disease characterized by extensive genomic and chromosomal instability (CIN), a hallmark that drives tumor evolution, intratumoral heterogeneity, therapeutic resistance, and poor clinical outcomes. Increasing evidence indicates that non-coding RNAs (ncRNAs) are important regulators of genome maintenance and chromosome stability. However, their specific contributions to CIN and the strength of the available evidence remain incompletely understood. This review examines the role of the major ncRNA classes, including circular RNAs, microRNAs, PIWI-interacting RNAs, small nucleolar RNAs, and long non-coding RNAs, in the regulation of CIN-related processes in breast cancer. We discuss the molecular mechanisms by which these ncRNAs regulate key pathways involved in CIN, while critically evaluating the strength of the experimental evidence supporting their functional roles. We also examine their associations with distinct breast cancer molecular subtypes and assess their potential as biomarkers and therapeutic targets, highlighting current limitations and knowledge gaps that hinder clinical translation. Collectively, the available evidence supports an emerging role for ncRNAs as regulators of CIN while underscoring the need for further mechanistic and subtype-specific studies to validate their clinical utility.

DNA repair↗
PubMed2005

p53 regulation and function in renal cell carcinoma.

Loss of p53 function is a critical event in tumor evolution. This occurs through a range of molecular events, typically a missense p53 mutation followed by loss of heterozygosity. In many cancers, there is compelling evidence that cells that can compromise p53 function have a selective advantage. The situation in renal cell carcinoma is unclear. It has recently been suggested that p53 function is unusually compromised in renal carcinoma cells by a novel dominant, MDM2/p14ARF-independent mechanism. This is hard to reconcile with other recent studies that have identified p53 as an important prognostic indicator. Indeed, one of these latter studies found that the best predictor of poor outcome was the presence of high levels of both p53 (usually indicative of p53 mutation) and MDM2. Thus, it is important that we gain a clearer understanding of the regulation of p53 and the role of MDM2 in renal cell cancer. To address this, we have investigated the transcriptional activity of p53 in a panel of renal cell carcinoma cell lines and the contribution of MDM2 and p14ARF to p53 regulation. We have found that p53 is functional in p53 wild-type renal cell carcinoma cells and that this activity is significantly regulated by MDM2 and to a much lesser extent by p14ARF. Moreover, following induction of DNA damage with UV, the p53 response in these cells is intact. Thus, future studies of renal cell carcinoma that focus on p53 and MDM2 and their role in determining disease outcome will be required to create a better understanding of this notoriously difficult to manage disease.

Carcinoma, Renal Cell↗
PubMed2026

A stratified urine-based molecular diagnostic and prognostic model for non-muscle-invasive bladder cancer management.

BACKGROUND: Non-muscle-invasive bladder cancer (NMIBC) is characterized by a high recurrence rate requiring lifelong cystoscopic surveillance. Existing urine-based molecular assays mainly rely on mutations or methylation, which fail to capture large-scale genomic instability. Copy number variation (CNV) profiling offers complementary information on tumor evolution and aggressiveness, but its application in urinary diagnosis remains limited. We aimed to integrate CNV and DNA methylation signals from urinary DNA to establish a noninvasive and biologically informed stratified diagnostic model for NMIBC recurrence surveillance and risk stratification. METHODS: Urine samples were prospectively collected from 91 patients (75 evaluable) between June 2021 and August 2023. Shallow whole-genome sequencing (sWGS) was used to detect CNVs at chromosomal arm and focal gene levels, while ONECUT2 promoter methylation was quantified by qPCR. Diagnostic and prognostic performance was evaluated by ROC analysis, Kaplan-Meier survival, and stratified recurrence assessment. RESULTS: We evaluated a stratified diagnostic model combining CNV and ONECUT2 methylation testing in a cohort of 79 patients. CNV analysis alone showed high specificity (0.923) for NMIBC diagnosis. A combined model, using CNV as an initial screen followed by ONECUT2 methylation testing in CNV-positive cases, achieved a sensitivity of 0.783, specificity of 0.981, and a negative predictive value (NPV) of 0.911. This approach reduced the number of required ONECUT2 tests by 35% and identified a high proportion of true-negative patients (98.1%), which may help reduce unnecessary cystoscopy procedures. The model also demonstrated significant prognostic value, with the molecularly defined high-risk group showing significantly shorter recurrence-free survival (RFS) than the low-risk group (median RFS: 4.33 months vs. not reached; p&#x2009;<&#x2009;0.001). Additional, in patients with initially negative cystoscopy after urine sample collection, the model demonstrated a predictive accuracy of 0.922 for recurrence, with molecular positivity observed a median of 9.6 months prior to clinical diagnosis. CONCLUSIONS: Integrating CNV and DNA methylation profiling from urinary DNA provides a powerful and noninvasive molecular framework for NMIBC surveillance. By combining early epigenetic changes with genomic instability signals, this approach enhances recurrence risk assessment and enables earlier detection compared with conventional cystoscopy. It offers a practical route toward personalized and adaptive post-treatment monitoring of NMIBC. TRIAL REGISTRATION: NCT04994197.

Humans↗
PubMed2002

Comprehensive analysis of genomic alterations in gliosarcoma and its two tissue components.

Gliosarcoma is a variant of glioblastoma multiforme characterized by two components displaying gliomatous or sarcomatous differentiation. We investigated 38 gliosarcomas for aberrations of tumor-suppressor genes and proto-oncogenes that are commonly altered in glioblastomas. Amplification of CDK4, MDM2, EGFR, and PDGFRA were found in 11% (4/35), 8% (3/38), 8% (3/38), and 3% (1/35) of the tumors, respectively. Nine of 38 gliosarcomas (24%) carried TP53 mutations. PTEN mutations were identified in 45% (9/20) of the investigated tumors. Twenty gliosarcomas were analyzed by comparative genomic hybridization (CGH). Chromosomal imbalances commonly detected were gains on chromosomes 7 (15/20; 75%), X (4/20; 20%), 9q, and 20q (3/20, 15% each); and losses on chromosomes 10 and 9p (7/20, 35% each), and 13q (3/20, 15%). Five different high-level amplifications were mapped to 4q12-q21 (1 case), 6p21 (1 case), 7p12 (2 cases), proximal 12q (4 cases), and 14q32 (1 case) by CGH. Southern blot and/or differential PCR analyses identified amplification of PDGFRA (4q12), CCND3 (6p21), EGFR (7p12), CDK4 (12q14) and/or MDM2 (12q14.3-q15), and AKT1 (14q32.3) in the respective tumors. Separate analysis of the gliomatous and sarcomatous components of eight gliosarcomas by CGH after microdissection and universal DNA amplification revealed that both components shared 57% of the chromosomal imbalances detected. Taken together, our data indicate that the genomic changes in gliosarcomas closely resemble those found in glioblastomas. However, the number of chromosomes involved in imbalances in gliosarcomas was significantly lower than that in glioblastomas, indicating a higher genomic stability in gliosarcomas. In addition, we provide further support for the hypothesis that the gliomatous and sarcomatous components are derived from a single precursor cell clone, which progressed into subclones with distinct morphological features during tumor evolution. According to our data, gain/amplification of genes on proximal 12q may facilitate the development of a sarcomatous phenotype.

Adult↗
PubMed1996

Pleomorphic xanthoastrocytoma: some observations.

The authors describe 3 cases of cerebral pleomorphic xanthoastrocytoma, one of which has an unusual neuroradiological appearance, and review the clinical and prognostic features of the 96 cases reported in the literature. Pleomorphic xanthoastrocytoma is a neuroectodermal tumor that affects young patients, in a superficial or supratentorial site, most frequently at the temporal level. It is difficult to formulate a differential diagnosis with other neuroectodermal tumors or with meningioma on the basis et neuroradiological appearance, as demonstrated by one of the cases reported here. The prognosis of this tumor is very good, regardless of the type of treatment performed, although both relapse and, more rarely, malignant tumor evolution are possible.

Adolescent↗
PubMed1997

Osteoblastoma of the calvaria: report of two cases diagnosed with MRI and clinical review.

The authors describe 2 cases of osteoblastoma of the calvaria and review the clinical features of the 28 cases reported in the world literature. Benign osteoblastoma is a rare tumor that effects young patients, most frequently at temporal level. On the basis of its neuroradiological appearance, it is difficult to formulate a differential diagnosis against other osteoblastic tumors or against osteoid osteoma. In only a few cases MRI findings are reported. In our cases, MRI was more effective than CT scans and radiographs for evaluating the intracranial and intraosseous extension of the tumor. The definitive diagnosis was obtained by combining the histopathological features of the tumor with the clinical and radiological data. The prognosis of this tumor is very good regardless of the type of treatment performed, although both relapse and, more rarely, malignant tumor evolution are possible.

Adult↗