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1.
Front Pediatr ; 12: 1378608, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39108689

RESUMEN

Background: Pleomorphic xanthoastrocytoma (PXA) is a rare brain tumor that accounts for <1% of all gliomas. An in-depth understanding of PXA's molecular makeup remains a work in progress due to its limited numbers globally. Separately, spontaneous intracranial hemorrhage (pICH) is an uncommon but potentially devastating emergency in young children, often caused by vascular malformations or underlying hematological conditions. We describe an interesting case of a toddler who presented with pICH, later found to have a PXA as the underlying cause of hemorrhage. Further molecular interrogation of the tumor revealed a neurotrophic tyrosine receptor kinase (NTRK) gene fusion and CDKN2A deletion more commonly seen in infantile high-grade gliomas. The unusual clinicopathological features of this case are discussed in corroboration with published literature. Case presentation: A previously well 2-year-old male presented with acute drowsiness and symptoms of increased intracranial pressure secondary to a large right frontoparietal intracerebral hematoma. He underwent an emergency craniotomy and partial evacuation of the hematoma for lifesaving measures. Follow-up neuroimaging reported a likely right intra-axial tumor with hemorrhagic components. Histology confirmed the tumor to be a PXA (WHO 2). Additional molecular investigations showed it was negative for BRAFV600E mutation but was positive for CDKN2A homozygous deletion and a unique neurotrophic tyrosine receptor kinase (NTRK) gene fusion. The patient subsequently underwent second-stage surgery to proceed with maximal safe resection of the remnant tumor, followed by the commencement of adjuvant chemotherapy. Conclusion: To date, there are very few pediatric cases of PXA that present with spontaneous pICH and whose tumors have undergone thorough molecular testing. Our patient's journey highlights the role of a dedicated multidisciplinary neuro-oncology team to guide optimal treatment.

2.
Diagn Cytopathol ; 52(2): E34-E38, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37837283

RESUMEN

Squamoid cyst of pancreatic duct is a rare benign pancreatic lesion that is rarely encountered in fine-needle aspiration (FNA) and surgical resection specimens. Pancreatic stones can be seen in chronic pancreatitis, but stone-related crystals have previously not been described in pancreatic cytology. Presented here is a case report of a squamoid cyst of pancreatic duct with concurrent pancreatic duct stones. We describe the cytomorphology of this benign cyst, as well as the remarkable finding of polymorphous crystals on cyst fluid aspirate. We also describe the histology of the surgically resected cystic lesion. With the increase in detection of incidental pancreatic cysts on imaging, this case highlights the importance of awareness and recognition of benign non-neoplastic epithelial cysts on FNA sampling to avoid overtreatment. The presence of crystals on pancreatic FNA is an unusual finding, likely representing calcium carbonate crystals related to the formation of pancreatic duct stones.


Asunto(s)
Quiste Pancreático , Neoplasias Pancreáticas , Humanos , Biopsia con Aguja Fina , Páncreas/patología , Quiste Pancreático/patología , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/patología
3.
Clin Transplant ; 36(8): e14717, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35598116

RESUMEN

INTRODUCTION: To evaluate the initial use of label-free second harmonic generation (SHG) imaging with two-photon excitation (2PE) auto-fluorescence in multiphoton microscopy (MPM) for the quantification of collagen/fibrosis on preimplantation biopsies of extended criteria donors (ECD). MATERIALS AND METHODS: Twenty preimplantation core biopsies were extracted from 10 donor kidney samples, of which originated from seven donors. Kidney Donor Profile Index (KDPI) and Remuzzi scores of biopsies were calculated. Collagen parameters measured included quantification by the Collagen Area Ratio in Total Tissue (CART) and qualitative measurements by Collagen Reticulation Index (CRI). RESULTS: Biopsies classified with > 85% KDPI scores had significantly higher CART (p = .011) and lower CRI values (p = .025) than biopsies with ≤ 85% KDPI scores. Increase in CRI values correlated significantly with rise in recipient creatinine levels 1-year post-transplant (p = .027; 95% CI: 4.635-66.797). CONCLUSION: MPM is an evolving technology that enables the quantification of the amount (CART) and quality (CRI) of collagen deposition in unstained preimplantation biopsies of donor kidneys stratified by KDPI scores. This initial evaluation found significant differences in both parameters between donor kidneys with more or less than 85% KDPI.


Asunto(s)
Trasplante de Riñón , Enfermedades Pulmonares Intersticiales , Colágeno , Fibrosis , Supervivencia de Injerto , Humanos , Riñón/patología , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Microscopía , Estudios Retrospectivos , Donantes de Tejidos
4.
BMJ Case Rep ; 15(1)2022 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-35027387

RESUMEN

Phyllodes tumours occurring in pregnancy are very rare. While most cases presented as rapidly enlarging masses, we present a benign phyllodes tumour which had the most growth in the first half of pregnancy followed by gradual growth in the latter half of pregnancy and lactation, as characterised on ultrasound imaging. This is the first report, to the best of our knowledge, which has objective measurements of the lesion before, during and after pregnancy. It also highlighted the need for a vigilant approach to fibroepithelial lesions in pregnancy, instead of attributing the growth of these lesions solely to hormonal changes.


Asunto(s)
Neoplasias de la Mama , Tumor Filoide , Lactancia Materna , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Lactancia , Tumor Filoide/diagnóstico por imagen , Tumor Filoide/cirugía , Embarazo , Ultrasonografía
5.
FASEB J ; 36(1): e22082, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34918389

RESUMEN

Vitamin D deficiency is associated with risk of several common cancers, including colorectal cancer (CRC). Here we have utilized patient derived epithelial organoids (ex vivo) and CRC cell lines (in vitro) to show that calcitriol (1,25OHD) increased the expression of the CRC tumor suppressor gene, CDH1, at both the transcript and protein level. Whole genome expression analysis demonstrated significant differential expression of a further six genes after 1,25OHD treatment, including genes with established links to carcinogenesis GADD45, EFTUD1 and KIAA1199. Furthermore, gene ontologies relevant to carcinogenesis were enriched by 1,25OHD treatment (e.g., 'regulation of Wnt signaling pathway', 'regulation of cell death'), with common enriched processes across in vitro and ex vivo cultures including 'negative regulation of cell proliferation', 'regulation of cell migration' and 'regulation of cell differentiation'. Our results identify genes and pathways that are modifiable by calcitriol that have links to CRC tumorigenesis. Hence the findings provide potential mechanism to the epidemiological and clinical trial data indicating a causal association between vitamin D and CRC. We suggest there is strong rationale for further well-designed trials of vitamin D supplementation as a novel CRC chemopreventive and chemotherapeutic agent.


Asunto(s)
Antineoplásicos/farmacología , Carcinogénesis/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas de Neoplasias/biosíntesis , Neoplasias/metabolismo , Transcriptoma/efectos de los fármacos , Vitamina D/análogos & derivados , Células CACO-2 , Células HCT116 , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Vitamina D/farmacología
6.
Int J Cancer ; 149(5): 1100-1108, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33937989

RESUMEN

Site-specific variation in colorectal cancer (CRC) incidence, biology and prognosis are poorly understood. We sought to determine whether common genetic variants influencing CRC risk might exhibit topographical differences on CRC risk through regional differences in effects on gene expression in the large bowel mucosa. We conducted a site-specific genetic association study (10 630 cases, 31 331 controls) to identify whether established risk variants exert differential effects on risk of proximal, compared to distal CRC. We collected normal colorectal mucosa and blood from 481 subjects and assessed mucosal gene expression using Illumina HumanHT-12v4 arrays in relation to germline genotype. Expression quantitative trait loci (eQTLs) were explored by anatomical location of sampling. The rs3087967 genotype (chr11q23.1 risk variant) exhibited significant site-specific effects-risk of distal CRC (odds ratio [OR] = 1.20, P = 8.20 × 10-20 ) with negligible effects on proximal CRC risk (OR = 1.05, P = .10). Expression of 1261 genes differed between proximal and distal colonic mucosa (top hit PRAC gene, fold-difference = 10, P = 3.48 × 10-57 ). In eQTL studies, rs3087967 genotype was associated with expression of 8 cis- and 21 trans-genes. Four of these (AKAP14, ADH5P4, ASGR2, RP11-342M1.7) showed differential effects by site, with strongest trans-eQTL signals in proximal colonic mucosa (eg, AKAP14, beta = 0.61, P = 5.02 × 10-5 ) and opposite signals in distal mucosa (AKAP14, beta = -0.17, P = .04). In summary, genetic variation at the chr11q23.1 risk locus imparts greater risk of distal rather than proximal CRC and exhibits site-specific differences in eQTL effects in normal mucosa. Topographical differences in genomic control over gene expression relevant to CRC risk may underlie site-specific variation in CRC. Results may inform individualised CRC screening programmes.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Mucosa Intestinal/metabolismo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Transcriptoma , Adulto Joven
8.
Gland Surg ; 9(5): 1764-1787, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33224854

RESUMEN

The Bethesda System for Reporting Thyroid Cytopathology has paved the way for comparisons of the practice of thyroid cytology in many different regions. However, there have been comparatively few studies documenting differences between Asian and non-Asian practice. Here, we aim to compare a few key parameters between the two regions, focusing on the indeterminate category of atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS). We compared its incidence, resection rates (RRs), risk of malignancy (ROM), rate of repeat fine needle aspiration (rFNA), ROMs of cytomorphologic subcategories of nuclear atypia (AUS-N) vs. architectural atypia (AUS-A), and, finally, the incidence of papillary thyroid carcinoma (PTC) vs. follicular neoplasms (FNs) in resected AUS/FLUS cases in Asian and non-Asian regions. Where possible, these metrics were compared with the Singapore experience from a tertiary referral institution. While the incidence of AUS/FLUS was similar in both regions, we found geographical differences in the RRs and ROMs, which may reflect a higher collective threshold for surgery in Asian countries. However, both cohorts showed higher ROMs in the AUS-N subcategory as compared to the AUS-A subcategory, supporting the subclassification of the AUS/FLUS based on the presence of nuclear atypia. We also observed a higher incidence of AUS-N coupled with a higher incidence of PTC in resected AUS/FLUS nodules in Asian cohorts, while AUS-A and follicular-patterned neoplasms featured more prominently in the non-Asian cohorts. These incidences may account for the starkly different molecular approaches that we noted-in Asian (chiefly Korean and Chinese) centers, BRAF mutational analysis was favored, while gene panels and gene expression classifiers were more frequently applied in non-Asian centers (chiefly in the United States of America). Overall, the data from Singapore appears more closely aligned to non-Asian trends, despite its geographical location in Southeast Asia and its predominantly Asian population. We conclude that there is significant heterogeneity in the outcomes of the AUS/FLUS categories between and within regions, which is only partially explained by regional variations, and may also reflect different regional diagnostic and management practices. This highlights the importance of understanding the local context in the interpretation of indeterminate Bethesda categories, rather than adopting a "one-size fits all" approach.

9.
Urology ; 144: 249-254, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32681916

RESUMEN

OBJECTIVE: To utilize Multiphoton Microscopy (MPM) as a novel imaging technique to characterize and quantify collagen at the Renal Cell Carcinoma Pseudocapsule, to assess for both intra-tumoral and inter-tumoral variation of collagen characteristics. MPM combines Second Harmonic Generation and Two Photon Excitation Fluorescence to image extracellular matrix architecture. METHODS: Twenty partial nephrectomy specimen tissues were retrieved, cut into 5-micron sections, mounted on slides and deparaffinized. The pseudocapsules (PCs) were imaged with 2X and 20X objective at selected Regions of Interest. Corresponding clinical information was retrieved. PC thickness was determined. Collagen parameters measured included quantification by the Collagen Area Ratio, and qualitative measurements by the Collagen Fiber Density and Collagen Reticulation Index. RESULTS: The boundaries between tumor, PC and normal renal parenchyma were distinguished by MPM without need for staining. In the thickest areas of the PC, collagen content and density were quantitatively higher compared to the thinnest areas. Median Collagen Area Ratio was higher in the thickest compared to the thinnest areas of the PC (P = .01). Clear Cell RCC specimens had a consistently higher Collagen Fiber Density in both the thickest and thinnest areas compared to non-Clear Cell RCC specimens (P = .02). CONCLUSIONS: We demonstrated the ability of MPM to quantify collagen characteristics of PCs without fluorescent labeling. Tumor enucleation for Renal Cell Carcinoma along its PC remains debatable with regards to oncological safety. Even with a complete and intact PC, the PC is not a homogenous structure, and varies in its thickness and its collagen characteristics within, and between tumors.


Asunto(s)
Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/cirugía , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Nefrectomía , Anciano , Femenino , Humanos , Masculino , Microscopía de Fluorescencia por Excitación Multifotónica , Persona de Mediana Edad , Nefrectomía/métodos , Estudios Retrospectivos
10.
Sci Rep ; 5: 16286, 2015 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-26553438

RESUMEN

Whilst common genetic variation in many non-coding genomic regulatory regions are known to impart risk of colorectal cancer (CRC), much of the heritability of CRC remains unexplained. To examine the role of recurrent coding sequence variation in CRC aetiology, we genotyped 12,638 CRCs cases and 29,045 controls from six European populations. Single-variant analysis identified a coding variant (rs3184504) in SH2B3 (12q24) associated with CRC risk (OR = 1.08, P = 3.9 × 10(-7)), and novel damaging coding variants in 3 genes previously tagged by GWAS efforts; rs16888728 (8q24) in UTP23 (OR = 1.15, P = 1.4 × 10(-7)); rs6580742 and rs12303082 (12q13) in FAM186A (OR = 1.11, P = 1.2 × 10(-7) and OR = 1.09, P = 7.4 × 10(-8)); rs1129406 (12q13) in ATF1 (OR = 1.11, P = 8.3 × 10(-9)), all reaching exome-wide significance levels. Gene based tests identified associations between CRC and PCDHGA genes (P < 2.90 × 10(-6)). We found an excess of rare, damaging variants in base-excision (P = 2.4 × 10(-4)) and DNA mismatch repair genes (P = 6.1 × 10(-4)) consistent with a recessive mode of inheritance. This study comprehensively explores the contribution of coding sequence variation to CRC risk, identifying associations with coding variation in 4 genes and PCDHG gene cluster and several candidate recessive alleles. However, these findings suggest that recurrent, low-frequency coding variants account for a minority of the unexplained heritability of CRC.


Asunto(s)
Neoplasias Colorrectales/genética , Variación Genética , Factor de Transcripción Activador 1/genética , Proteínas Adaptadoras Transductoras de Señales , Alelos , Cadherinas/genética , Estudios de Casos y Controles , Neoplasias Colorrectales/patología , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Desequilibrio de Ligamiento , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Proteínas/genética , Población Blanca/genética
11.
J Clin Oncol ; 32(23): 2430-9, 2014 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-25002714

RESUMEN

PURPOSE: We investigated whether the plasma level of 25-hydroxyvitamin D (25-OHD) after a diagnosis of colorectal cancer (CRC) influences survival outcome. PATIENTS AND METHODS: We prospectively studied 1,598 patients with stage I to III CRC. We sought association between plasma 25-OHD and stage-specific survival and tested for interaction between 25-OHD level and variation at the vitamin D receptor (VDR) gene locus. Blood was sampled postoperatively, and plasma was assayed for 25-OHD by liquid chromatography-tandem mass spectrometry. VDR polymorphisms (rs1544410, rs10735810, rs7975232, rs11568820) were genotyped, and haplotypes were inferred by using BEAGLE software. We tested for association between survival and 25-OHD, VDR genotype/haplotype, and after applying a VDR genotype-25-OHD interaction term. We conducted Kaplan-Meier survival analysis and used Cox proportional hazards models to estimate adjusted hazard ratios (HRs). RESULTS: We found strong associations between plasma 25-OHD concentration and CRC-specific (P = .008) and all-cause mortality (P = .003). Adjusted HRs were 0.68 (95% CI, 0.50 to 0.90) and 0.70 (95% CI, 0.55 to 0.89), respectively (highest v lowest 25-OHD tertile), particularly in stage II disease (HR, 0.44; P = .004 for CRC-specific mortality). We detected gene-environment interactions between 25-OHD concentration and rs11568820 genotype for CRC-specific (P = .008) and all-cause (P = .022) mortality, number of protective alleles (P = .004 and P = .018, respectively), and GAGC haplotype at the VDR locus for all-cause mortality (P = .008). CONCLUSION: In patients with stage I to III CRC, postoperative plasma vitamin D is associated with clinically important differences in survival outcome, higher levels being associated with better outcome. We observed interactions between 25-OHD level and VDR genotype, suggesting a causal relationship between vitamin D and survival. The influence of vitamin D supplementation on CRC outcome will require further investigation.


Asunto(s)
Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/mortalidad , Vitamina D/análogos & derivados , Estudios de Casos y Controles , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Polimorfismo Genético , Estudios Prospectivos , Receptores de Calcitriol/genética , Factores de Riesgo , Escocia/epidemiología , Vitamina D/sangre , Vitamina D/metabolismo
12.
Nat Genet ; 44(7): 770-6, 2012 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-22634755

RESUMEN

We performed a meta-analysis of five genome-wide association studies to identify common variants influencing colorectal cancer (CRC) risk comprising 8,682 cases and 9,649 controls. Replication analysis was performed in case-control sets totaling 21,096 cases and 19,555 controls. We identified three new CRC risk loci at 6p21 (rs1321311, near CDKN1A; P = 1.14 × 10(-10)), 11q13.4 (rs3824999, intronic to POLD3; P = 3.65 × 10(-10)) and Xp22.2 (rs5934683, near SHROOM2; P = 7.30 × 10(-10)) This brings the number of independent loci associated with CRC risk to 20 and provides further insight into the genetic architecture of inherited susceptibility to CRC.


Asunto(s)
Neoplasias Colorrectales/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , ADN Polimerasa III/genética , Proteínas de la Membrana/genética , Estudios de Casos y Controles , Sitios Genéticos , Predisposición Genética a la Enfermedad , Variación Genética , Estudio de Asociación del Genoma Completo/métodos , Humanos
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