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14 result(s) for "Pyman, Jan"
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p53 immunohistochemistry in endometrial cancer: clinical and molecular correlates in the PORTEC-3 trial
Standard molecular classification of endometrial cancers (EC) is now endorsed by the WHO and identifies p53-abnormal (p53abn) EC as the subgroup with the poorest prognosis and the most likely to benefit from adjuvant chemo(radio)therapy. P53abn EC are POLE wildtype, mismatch repair proficient and show abnormal immunohistochemical (IHC) staining for p53. Correct interpretation of routinely performed p53 IHC has therefore become of paramount importance. We aimed to comprehensively investigate abnormal p53 IHC patterns and their relation to clinicopathological and molecular features. Tumor material of 411 molecularly classified high-risk EC from consenting patients from the PORTEC-3 clinical trial were collected. p53 IHC was successful in 408 EC and was considered abnormal when the tumor showed a mutant expression pattern (including subclonal): overexpression, null or cytoplasmic. The presence of pathogenic mutations was determined by next generation sequencing (NGS). Abnormal p53 expression was observed in 131/408 (32%) tumors. The most common abnormal p53 IHC pattern was overexpression (n = 89, 68%), followed by null (n = 12, 9%) and cytoplasmic (n = 3, 2%). Subclonal abnormal p53 staining was observed in 27 cases (21%), which was frequently but not exclusively, associated with POLE mutations and/or MMRd (n = 22/27; p < 0.001). Agreement between p53 IHC and TP53 NGS was observed in 90.7%, resulting in a sensitivity and specificity of 83.6% and 94.3%, respectively. Excluding POLEmut and MMRd EC, as per the WHO-endorsed algorithm, increased the accuracy to 94.5% with sensitivity and specificity of 95.0% and 94.1%, respectively. Our data shows that awareness of the abnormal p53 IHC patterns are prerequisites for correct EC molecular classification. Subclonal abnormal p53 expression is a strong indicator for POLEmut and/or MMRd EC. No significant differences in clinical outcomes were observed among the abnormal p53 IHC patterns. Our data support use of the WHO-endorsed algorithm and combining the different abnormal p53 IHC patterns into one diagnostic entity (p53abn EC).
Isolation and Characterization of Tumor Cells from the Ascites of Ovarian Cancer Patients: Molecular Phenotype of Chemoresistant Ovarian Tumors
Tumor cells in ascites are a major source of disease recurrence in ovarian cancer patients. In an attempt to identify and profile the population of ascites cells obtained from ovarian cancer patients, a novel method was developed to separate adherent (AD) and non-adherent (NAD) cells in culture. Twenty-five patients were recruited to this study; 11 chemonaive (CN) and 14 chemoresistant (CR). AD cells from both CN and CR patients exhibited mesenchymal morphology with an antigen profile of mesenchymal stem cells and fibroblasts. Conversely, NAD cells had an epithelial morphology with enhanced expression of cancer antigen 125 (CA125), epithelial cell adhesion molecule (EpCAM) and cytokeratin 7. NAD cells developed infiltrating tumors and ascites within 12-14 weeks after intraperitoneal (i.p.) injections into nude mice, whereas AD cells remained non-tumorigenic for up to 20 weeks. Subsequent comparison of selective epithelial, mesenchymal and cancer stem cell (CSC) markers between AD and NAD populations of CN and CR patients demonstrated an enhanced trend in mRNA expression of E-cadherin, EpCAM, STAT3 and Oct4 in the NAD population of CR patients. A similar trend of enhanced mRNA expression of CD44, MMP9 and Oct4 was observed in the AD population of CR patients. Hence, using a novel purification method we demonstrate for the first time a distinct separation of ascites cells into epithelial tumorigenic and mesenchymal non-tumorigenic populations. We also demonstrate that cells from the ascites of CR patients are predominantly epithelial and show a trend towards increased mRNA expression of genes associated with CSCs, compared to cells isolated from the ascites of CN patients. As the tumor cells in the ascites of ovarian cancer patients play a dominant role in disease recurrence, a thorough understanding of the biology of the ascites microenvironment from CR and CN patients is essential for effective therapeutic interventions.
Molecular correlates of platinum response in human high-grade serous ovarian cancer patient-derived xenografts
Improvement in the ability to target underlying drivers and vulnerabilities of high-grade serous ovarian cancer (HG-SOC) requires the development of molecularly annotated pre-clinical models reflective of clinical responses. We generated patient-derived xenografts (PDXs) from consecutive, chemotherapy-naïve, human HG-SOC by transplanting fresh human HG-SOC fragments into subcutaneous and intra-ovarian bursal sites of NOD/SCID IL2Rγnull recipient mice, completed molecular annotation and assessed platinum sensitivity. The success rate of xenografting was 83%. Of ten HG-SOC PDXs, all contained mutations in TP53, two were mutated for BRCA1, three for BRCA2, and in two, BRCA1 was methylated. In vivo cisplatin response, determined as platinum sensitive (progression-free interval ≥100 d, n = 4), resistant (progression-free interval <100 d, n = 3) or refractory (n = 3), was largely consistent with patient outcome. Three of four platinum sensitive HG-SOC PDXs contained DNA repair gene mutations, and the fourth was methylated for BRCA1. In contrast, all three platinum refractory PDXs overexpressed dominant oncogenes (CCNE1, LIN28B and/or BCL2). Because PDX platinum response reflected clinical outcome, these annotated PDXs will provide a unique model system for preclinical testing of novel therapies for HG-SOC. •High-grade serous ovarian cancer patient-derived xenografts from fragments (83% success).•In vivo platinum response (sensitive ≥ 100 d) consistent with patient outcome.•Three of four platinum-sensitive PDX contained mutations in BRCA1 or BRCA2.•All three platinum refractory PDX overexpressed dominant oncogenes.•These annotated PDX will enhance preclinical testing of novel therapies.
Pre-Vaccination Human Papillomavirus Genotypes and HPV16 Variants among Women Aged 25 Years or Less with Cervical Cancer
Background: In 2007, Australia introduced a national human papillomavirus (HPV) vaccination program. In 2017, the onset of cervical screening changed from 18 to 25 years of age, utilising human papillomavirus (HPV) nucleic acid testing. The objective of the study is to describe the HPV genotypes and HPV16 variants in biopsies from women ≤ 25 years of age with cervical carcinoma (CC) (cases), compared with those aged >25 years (controls), in a pre-vaccination cohort. Methods: HPV genotyping of archival paraffin blocks (n = 96) was performed using the INNO-LiPA HPV Genotyping assay. HPV16-positive samples were analysed for variants by type-specific PCR spanning L1, E2 and E6 regions. Results: HPV16 was the commonest genotype in cases (54.5%, 12/22) and controls (66.7%, 46/69) (p = 0.30), followed by HPV18 (36.3%, 8/22 vs. 17.3% 12/69, respectively) (p = 0.08). Furthermore, 90% (20/22) of cases and 84.1% (58/69) of controls were positive for HPV16 or 18 (p = 0.42); 100% (22/22) of cases and 95.7% (66/69) of controls had at least one genotype targeted by the nonavalent vaccine (p = 0.3). The majority of HPV16 variants (87.3%, 48/55) were of European lineage. The proportion of unique nucleotide substitutions was significantly higher in cases (83.3%, 10/12) compared with controls (34.1%, 15/44), (p < 0.003, χ2, OR 9.7, 95%CI 1.7–97.7). Conclusions: Virological factors may account for the differences in CCs observed in younger compared with older women. All CCs in young women in this study had preventable 9vHPV types, which is important messaging for health provider adherence to new cervical screening guidelines.
Histologic chorioamnionitis in preterm infants: correlation with brain magnetic resonance imaging at term equivalent age
Background To explore the associations between histologic chorioamnionitis with brain injury, maturation and size on magnetic resonance imaging (MRI) of preterm infants at term equivalent age. Methods Preterm infants (23–36 weeks’ gestational age) were recruited into two longitudinal cohort studies. Presence or absence of chorioamnionitis was obtained from placental histology and clinical data were recorded. MRI at term-equivalent age was assessed for brain injury (intraventricular haemorrhage, cysts, signal abnormalities), maturation (degree of myelination, gyral maturation) and size of cerebral structures (metrics and brain segmentation). Histologic chorioamnionitis was assessed as a predictor of MRI variables using linear and logistic regression, with adjustment for confounding perinatal variables. Results Two hundred and twelve infants were included in this study, 47 (22%) of whom had histologic chorioamnionitis. Histologic chorioamnionitis was associated with higher odds of intraventricular haemorrhage (odds ratio [OR] (95% confidence interval [CI]) = 7.4 (2.4, 23.1)), less mature gyral maturation (OR (95% CI) = 2.0 (1.0, 3.8)) and larger brain volume (mean difference in cubic centimeter (95% CI) of 14.1 (1.9, 26.2)); but all relationships disappeared following adjustment for perinatal variables. Conclusion Histologic chorioamnionitis was not independently associated with IVH, less mature gyral maturation or brain volume at term-equivalent age in preterm infants.
HPV16/18 prevalence in high-grade cervical lesions in an Australian population offered catch-up HPV vaccination
Using laser capture microdissection (LCM) and sensitive human papillomavirus (HPV) genotyping, we aimed to determine the distribution of vaccine-preventable types in cervical intraepithelial neoplasia grade 3 (CIN3) lesions and adenocarcinoma in situ (AIS) in young women in Victoria, Australia, offered catch-up HPV vaccination, as a baseline for ongoing vaccine impact monitoring. We also compared findings with available pre-vaccination estimates from women with HPV detected on concurrently-collected cytology samples. Consecutive histologically-confirmed CIN3/AIS biopsies were collected between May 2011 and December 2014 from vaccine-eligible women (born after 30th June 1981). Genotypes present in whole tissue sections (WTS) were determined by a sensitive reverse hybridisation assay; RHA kit HPV SPF10-LiPA25, v1 (Labo Bio-medical Products). Where multiple genotypes were detected, lesions were isolated using LCM and genotyped. Cervical cytology samples from a pre-vaccine cohort had been previously collected and genotyped using HPV Linear Array HPV Genotyping Test (Roche Diagnostics). Mixed-genotype detections in this cohort were resolved to single-lesion-attributable genotypes using hierarchical attribution. Overall, 213 and 530 cases were included from pre- and post-vaccine time-periods, respectively. In 18–25 year-olds, the proportion of HPV16/18-positive CIN3/AIS decreased significantly over time from 69% in 2001–2005 (pre-vaccine), to 62% in 2011–2012 (post-vaccine), to 47% in 2013–2014 (p-trend = 0.004). There was no significant change in HPV16/18 in 26–32 year-olds (p-trend = 0.15). In 2013/14, nonavalent vaccine types accounted for 80% of CIN3/AIS in 18–25 year old women and 90% in 26–32 year old women. Four to 8 years following implementation of HPV vaccination in Australia, approximately 70% of CIN3/AIS in young women was due to HPV16/18. Our data, despite some limitations due to change in methods between pre- and post-vaccine periods, suggests that for vaccine-eligible women aged 18–25 at the time of biopsy, the proportion of HPV16/18-attributable CIN3/AIS lesions is significantly declining post-vaccination.
Assessment of attribution algorithms for resolving CIN3-related HPV genotype prevalence in mixed-genotype biopsy specimens using laser capture microdissection as the reference standard
To make accurate determinations regarding potential and actual impact of HPV vaccine programs, precise estimates of genotype-specific contributions to disease are required for pre- and post-vaccine populations. Definitive determination of lesion-specific genotypes, particularly where multiple genotypes are detected in a sample, can be technically demanding and resource intensive; therefore, most prevalence studies use mathematical algorithms to adjust for multiple genotype detections. There are currently several algorithms, which can produce genotype estimates within a wide range of variability. The use of these for cervical cytology samples has recently been assessed for accuracy against a definitive reference standard, but none have yet been assessed for multiple-genotype-containing whole biopsy specimens. Using laser capture microdissection (LCM) on biopsy samples, lesion-specific genotype prevalence data were generated for a cohort of 516 young Australian women (aged 18–32 years) with cervical intraepithelial neoplasia grade 3 or adenocarcinoma in situ. Using whole tissue section genotype data from the same cohort, including 71 (13.7%) with multiple genotypes, lesion-associated genotype prevalence was estimated using four different attribution algorithms. The proportion of lesions attributable to HPV16 and HPV18 by LCM were 58.4% and 5%, respectively; hierarchical, proportional, single type/minimum and any type/maximum attribution estimates were comparable across genotypes. For analyses utilising whole tissue biopsy cervical specimens, attribution estimates are appropriate for estimating the proportional contribution of individual genotypes to lesions in a population.
How best to interpret mixed human papillomavirus genotypes in high-grade cervical intraepithelial neoplasia lesions
•Mixed HPV infections are not uncommon in cervical biopsies.•A single HPV genotype is associated with an independent cervical lesion.•LCM is an ideal method to attribute HPV genotype to specific cervical lesions.•LCM will improve assessment of vaccine. This study aimed to determine human papillomavirus (HPV) genotypes present in biopsy sections from young women of vaccine eligible age living in Victoria, Australia, with confirmed cervical intraepithelial neoplasia grade 3 (CIN3) or adenocarcinoma in situ (AIS) using laser capture microdissection (LCM). Histologically confirmed CIN3 or AIS positive biopsies from vaccine eligible women (born after 30th June 1981, n=169), between May 2011 and March 2013, were identified. CIN3 or AIS lesions were isolated from biopsy material using LCM, and the HPV genotypes present in whole tissue sections (WTS) as well as LCM-isolated lesion tissue were determined by a sensitive reverse hybridisation assay; RHA kit HPV SPF10-LiPA25, version 1 (Labo Bio-medical Products, Rijswijk, The Netherlands). One hundred and sixty-eight cases were shown to be HPV positive (99%), of which 20 (12%) had more than one HPV genotype detected using WTS-PCR. Evaluation by LCM of individual biopsies with mixed infections showed 18 cases (90%) had only one HPV genotype associated with each CIN3 lesion. HPV 16 was the most common HPV type, found in 95/168 cases (57%). LCM-PCR allowed us to confirm the presence of a single HPV genotype associated with each biologically separate CIN3 lesion, supporting the theory that only one virus type causes each independent CIN lesion. LCM will provide an important tool in assessing vaccine effectiveness in HPV vaccine programs.
Predictive Value of Magnetic Resonance Imaging in Assessing Myometrial Invasion in Endometrial Cancer: Is Radiological Staging Sufficient for Planning Conservative Treatment?
Objectives:There has been an increasing interest in accurately assessing tumors preoperatively to plan appropriate surgery or, in some low-risk patients, conservative treatment. We wish to determine the accuracy of magnetic resonance imaging (MRI) in predicting myometrial invasion in endometrial cancer and whether it is a safe and suitable tool for planning conservative treatment.Materials and Methods:We compared MRI scans and final histopathologic diagnoses of 111 patients with endometrioid adenocarcinoma over a 6-year period at a major tertiary centre. Data were analyzed collectively and according to histological differentiation and types of MRI scans (1.5 vs 3 T). Outcomes were presence versus absence of myometrial invasion and recently revised International Federation of Gynecology and Obstetrics stage IA (up to 50% myometrial invasion) versus deep invasion.Results:Magnetic resonance imaging had a high negative predictive value for the presence of deep invasion (87% overall and 95% for grade 1 disease). However, although the positive predictive value for the presence of any myometrial invasion was high, negative predictive values were poor (35% for all grades and 46% for grade 1). There was no difference between 1.5- and 3-T scanning.Conclusions:Magnetic resonance imaging is a suitable screening tool for the presence of stage IA disease under the newly revised International Federation of Gynecology and Obstetrics staging system. The significance of this finding will depend on whether clinicians are willing to treat all grade 1 stage IA disease (under the revised system) as low risk and to deem selected patients in this group suitable for more conservative treatment.