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result(s) for
"Ersen, Ayca"
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A single-center prospective study evaluating the relationship of tumor consistency on remission in acromegaly patients
by
Ozturk, Seda Duman
,
Danyeli, Ayca Ersen
,
Gokbel, Aykut
in
692/163
,
692/163/2743/1530
,
692/163/2743/2742/1738
2025
The nature of somatotroph adenomas has not been clearly revealed in studies. We consider that there are macroscopic differences in intraoperative tumor consistency in acromegaly patients. We aimed to determine whether there is a relationship between intraoperative tumor consistency and histopathological subtypes by planning a prospective study to determine whether these differences are significant. Between August 1997 and December 2021, 1118 patients with GH-secreting tumors underwent endoscopic endonasal surgery at our Pituitary Research Center. Between January 2022 and May 2023, pure GH-secreting adenomas operated via the endoscopic endonasal approach were sequentially categorized into three types(Type-1:Soft, Type-2:Mucinous/Adhesive, Type-3:Mix/Intermediate) according to the intraoperative tumor consistency. The final patient cohort consisted 218 cases. The ratio of densely granulated adenomas(DG-A) to sparsely granulated adenomas(SG-A) was as follows: Type-1, 89/11; Type-2, 5/95; Type-3, 13/5. Logistic regression revealed that Type-1 tumors were associated with a high remission rate(
p
= 0.011), and Type-2 were associated with SG-A(
p
< 0.001). Furthermore, no or weak staining for E-cadherin was associated with Type-2 tumors(
p
< 0.001). Surgeon could predict the prognosis and histopathological subtype of the pure somatotroph adenoma by observing the intraoperative tumor consistency. This could facilitate better intraoperative planning of patient-specific surgical strategies to increase the remission rates.
Journal Article
Optimal qMSP cutoff value for MGMT promoter methylation in glioblastoma and its validation for clinical significance
2025
Background
Glioblastoma (GBM) is the most common and aggressive primary brain tumor, with limited survival despite multimodal treatment strategies. O6-Methylguanine-DNA Methyltransferase (MGMT) promoter methylation is a well-established predictive biomarker for response to temozolomide (TMZ) therapy. However, determining an optimal quantitative methylation-specific PCR (qMSP) cut-off value remains a challenge in clinical practice.
Objective
This study aimed to establish an optimal qMSP cut-off value for MGMT promoter methylation and validate its prognostic significance in GBM patients. The impact of MGMT methylation status on survival outcomes was analyzed concerning surgical extent, tumor localization, and white matter tract involvement.
Methods
A retrospective analysis of 101 GBM patients (IDH-wildtype) diagnosed between 2008 and 2022 was performed. All patients underwent surgical resection (total/partial excision or stereotactic biopsy) followed by standard chemoradiotherapy. MGMT promoter methylation status was assessed using real-time qMSP. The optimal cut-off value was determined via receiver operating characteristic curve analysis. Kaplan-Meier survival analysis and Cox regression models evaluated the association between MGMT methylation levels, clinical characteristics, and overall survival (OS).
Results
Among 101 patients with IDH-wildtype glioblastoma, a qMSP cut-off value of 0.242% demonstrated strong diagnostic performance for MGMT methylation status (AUC = 0.875), with 78% sensitivity and 86% specificity. Patients with high methylation levels (≥ 0.242%) showed significantly longer median overall survival compared to those with low methylation (24 vs. 12 months;
p
= 0.006). This prognostic relevance persisted across surgical and anatomical subgroups. Multivariable Cox regression identified high qMSP methylation (HR ≈ 0.45,
p
< 0.001) and extent of resection ≥ 90% (HR ≈ 0.30,
p
= 0.002) as independent predictors of improved survival, whereas TERT promoter mutation (HR ≈ 1.9,
p
= 0.017) was associated with worse survival. Stratified analysis revealed that TERTp-mutant tumors with low methylation had the worst outcomes. Additionally, excisional surgery and neocortical tumor involvement were associated with significantly better survival (
p
= 0.0010 and
p
= 0.0218, respectively). These findings validate within our institutional setting the clinical utility of the 0.242% qMSP threshold for prognostic stratification in glioblastoma, although external multicenter validation is warranted before generalization to routine clinical practice.
Conclusion
The identified qMSP cut-off value (0.242) based on the procedure described in this study provides a robust prognostic stratification tool for GBM patients. High MGMT methylation correlates with improved survival, supporting its integration into clinical decision-making. Further multi-center validation studies are warranted to establish standardized MGMT assessment methodologies.
Journal Article
Diagnostic utility of SOX10 to distinguish malignant peripheral nerve sheath tumor from synovial sarcoma, including intraneural synovial sarcoma
by
Folpe, Andrew L
,
Horvai, Andrew E
,
Ersen, Ayca
in
692/53/2421
,
692/699/67/1798
,
692/699/67/1922
2014
Synovial sarcoma and malignant peripheral nerve sheath tumor pose a significant diagnostic challenge given similar histomorphology. The distinction is further complicated by similar immunophenotype and especially by occasional synovial sarcomas that present as intraneural tumors. Although the presence of a t(X;18) rearrangement or expression of TLE1 can help confirm the diagnosis of synovial sarcoma, negative results for these tests are not diagnostic of malignant peripheral nerve sheath tumor. The SOX10 transcription factor, a putative marker of neural crest differentiation, may have diagnostic utility in this differential, but immunohistochemical data are limited. The goal of the present study was to determine the diagnostic utility of SOX10 to discriminate between synovial sarcoma and malignant peripheral nerve sheath tumor. Forty-eight cases of malignant peripheral nerve sheath tumor, all from patients with documented neurofibromatosis, and 97 cases of genetically confirmed synovial sarcoma, including 4 intraneural synovial sarcomas, were immunohistochemically stained for SOX10. The stain was scored for intensity and fraction of cells staining. Thirty-two of 48 malignant peripheral nerve sheath tumors (67%) were SOX10-positive. The majority of malignant peripheral nerve sheath tumors showed ≥2+ staining, but staining did not correlate with grade. By contrast, only 7/97 (7%) synovial sarcomas were SOX10-positive. Only three synovial sarcomas showed ≥2+ staining but, importantly, two of these were intraneural synovial sarcoma. Therefore, SOX10 is a specific (93%), albeit not very sensitive (67%), diagnostic marker to support a diagnosis of malignant peripheral nerve sheath tumor over synovial sarcoma. Furthermore, the stain needs to be interpreted with caution in intraneural tumors in order to avoid a potential diagnostic pitfall. It remains to be determined whether SOX10-positive cells in intraneural synovial sarcoma represent entrapped Schwann cells, synovial sarcoma cells or both.
Journal Article
Preliminary findings of German-sourced ONC201 treatment in H3K27 altered pediatric pontine diffuse midline gliomas
by
Özek, M. Memet
,
Yaşar, Ahmet Harun
,
Tanrıkulu, Bahattin
in
Adolescent
,
Biopsy
,
Brain Stem Neoplasms - drug therapy
2023
Purpose
H3K27 altered pediatric pontine diffuse midline gliomas (pDMG) have a poor prognosis, and conventional treatments offer limited benefits. However, recent advancements in molecular evaluations and targeted therapies have shown promise. The aim of this retrospective analysis was to evaluate the effectiveness of German-sourced ONC201, a selective antagonist of dopamine receptor DRD2, for the treatment of pediatric H3K27 altered pDMGs.
Methods
Pediatric patients with H3K27 altered pDMG treated between January 2016 and July 2022 were included in this retrospective analysis. Tissue samples were acquired from all patients via stereotactic biopsy for immunohistochemistry and molecular profiling. All patients received radiation treatment with concurrent temozolomide, and those who could acquire GsONC201 received it as a single agent until progression. Patients who could not obtain GsONC201 received other chemotherapy protocols.
Results
Among 27 patients with a median age of 5.6 years old (range 3.4–17.9), 18 received GsONC201. During the follow-up period, 16 patients (59.3%) had progression, although not statistically significant, the incidence of progression tended to be lower in the GsONC201 group. The median overall survival (OS) of the GsONC201 group was considerably longer than of the non-GsONC201 group (19.9 vs. 10.9 months). Only two patients receiving GsONC201 experienced fatigue as a side effect. 4 out of 18 patients in the GsONC201 group underwent reirradiation after progression.
Conclusion
In conclusion, this study suggests that GsONC201 may improve OS in pediatric H3K27-altered pDMG patients without significant side effects. However, caution is warranted due to retrospective design and biases, highlighting the need for further randomized clinical studies to validate these findings.
Graphical Abstract
Journal Article
Susceptibility-Weighted MRI for Predicting NF-2 Mutations and S100 Protein Expression in Meningiomas
by
Dindar, Sukru Samet
,
Azamat, Sena
,
Pamir, M. Necmettin
in
Blood products
,
Blood vessels
,
Brain cancer
2024
S100 protein expression levels and neurofibromatosis type 2 (NF-2) mutations result in different disease courses in meningiomas. This study aimed to investigate non-invasive biomarkers of NF-2 copy number loss and S100 protein expression in meningiomas using morphological, radiomics, and deep learning-based features of susceptibility-weighted MRI (SWI). This retrospective study included 99 patients with S100 protein expression data and 92 patients with NF-2 copy number loss information. Preoperative cranial MRI was conducted using a 3T clinical MR scanner. Tumor volumes were segmented on fluid-attenuated inversion recovery (FLAIR) and subsequent registration of FLAIR to high-resolution SWI was performed. First-order textural features of SWI were extracted and assessed using Pyradiomics. Morphological features, including the tumor growth pattern, peritumoral edema, sinus invasion, hyperostosis, bone destruction, and intratumoral calcification, were semi-quantitatively assessed. Mann–Whitney U tests were utilized to assess the differences in the SWI features of meningiomas with and without S100 protein expression or NF-2 copy number loss. A logistic regression analysis was used to examine the relationship between these features and the respective subgroups. Additionally, a convolutional neural network (CNN) was used to extract hierarchical features of SWI, which were subsequently employed in a light gradient boosting machine classifier to predict the NF-2 copy number loss and S100 protein expression. NF-2 copy number loss was associated with a higher risk of developing high-grade tumors. Additionally, elevated signal intensity and a decrease in entropy within the tumoral region on SWI were observed in meningiomas with S100 protein expression. On the other hand, NF-2 copy number loss was associated with lower SWI signal intensity, a growth pattern described as “en plaque”, and the presence of calcification within the tumor. The logistic regression model achieved an accuracy of 0.59 for predicting NF-2 copy number loss and an accuracy of 0.70 for identifying S100 protein expression. Deep learning features demonstrated a strong predictive capability for S100 protein expression (AUC = 0.85 ± 0.06) and had reasonable success in identifying NF-2 copy number loss (AUC = 0.74 ± 0.05). In conclusion, SWI showed promise in identifying NF-2 copy number loss and S100 protein expression by revealing neovascularization and microcalcification characteristics in meningiomas.
Journal Article
Prognostic Factors in Elderly Patients With Diffuse Large B-Cell Lymphoma and Their Treatment Results
by
Danyeli, Ayça Ersen
,
Özkal, Şermin
,
Adıyaman, Süleyman Cem
in
b-cell neoplasms
,
Biopsy
,
Cancer therapies
2019
Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma (NHL). The treatment of older NHL patients has always been a struggle; however, treatment statistics have begun showing favorable results similar to those of younger DLBCL patients thanks to newer treatment protocols. Here, we analyze the progress of our own elderly DLBCL patients who were followed between 2000 and 2016 in our center.
Eighty-seven DLBCL patients, who were diagnosed and treated in the Dokuz Eylül University Department of Hematology between 2000 and 2016, were included in this study. Median age was 72 (65-89) years and 13 (14.9%) patients were older than 80 years.
Median follow-up time was 19 months and 45 patients (51.7%) died during the follow-up period. Median overall survival (OS) was 55 months and median progression-free survival was calculated as 27 months. Sixty-three patients (72.4%) received standard R-CHOP therapy. Complete response was seen in 46 (52.9%) patients. The median survival time for patients who had complete response was 136 months (p<0.001); however, OS was not statistically different between older (>80 years) and younger patients (p=0.236).
According to our findings, we think that being able to complete standard R-CHOP therapy is vital for the survival rate of elderly DLBCL patients.
Journal Article
Frequency and Role of CDKN2A Deletion in High-Risk Pituitary Neuroendocrine Tumors
by
Danyeli, Ayça Ersen
,
Kara Müjdat
,
Necmettin, Pamir M
in
Brain cancer
,
Chromosome 9
,
Fluorescence in situ hybridization
2020
The underlying mechanisms of aggressive pituitary neuroendocrine tumors (pitNETs) are still unclear. The p16 protein, encoded by the CDKN2A tumor suppressor gene on chromosome 9p21, is commonly reported to be lost in numerous types of cancer. For this reason, this study examined to examine the status of homozygous deletion of CDKN2A in high-risk pitNETs. Thirty-eight high-risk pitNETs (30 male, 8 female) were analyzed for CDKN2A deletion by fluorescent in situ hybridization (FISH). Demographic characteristics such as sex, patient age at operation, and sellar magnetic resonance imaging findings including tumor size and invasion status were recorded. The frequency of CDKN2A homozygous deletion by FISH was 3/38 (7.89%) in the high-risk pitNET group. All of these three cases with CDKN2A homozygous deletion were invasive densely granulated lactotroph tumors (p = 0.000). CDKN2A deletion was not correlated with patient age, sex, cavernous sinus invasion (CSI), and tumor size (p > 0.05). The Ki-67 proliferation index was significantly correlated with CDKN2A homozygous deletion (p = 0.003). The mean Ki-67 proliferation index was 10.7% in pitNETs with CDKN2A homozygous deletion and the Ki-67 proliferation index in the whole study group was 4.1%. CSI was significantly correlated with the morphofunctional tumor types including lactotroph tumor, invasive null cell tumor, and invasive gonadotroph tumor (p = 0.021). These findings suggest a close correlation between inactivation of p16 gene and invasive lactotroph tumors. Further investigations are needed to expand on the mechanism of p16 (CDKN2A) gene deletion in high-risk pitNETs.
Journal Article
Information theory approaches to improve glioma diagnostic workflows in surgical neuropathology
by
Becker, Aline Paixao
,
Garagorry Guerra, Francisco Jose
,
Cevik, Lokman
in
1p/19q codeletion
,
Analysis
,
Biomarkers
2022
Aims Resource‐strained healthcare ecosystems often struggle with the adoption of the World Health Organization (WHO) recommendations for the classification of central nervous system (CNS) tumors. The generation of robust clinical diagnostic aids and the advancement of simple solutions to inform investment strategies in surgical neuropathology would improve patient care in these settings. Methods We used simple information theory calculations on a brain cancer simulation model and real‐world data sets to compare contributions of clinical, histologic, immunohistochemical, and molecular information. An image noise assay was generated to compare the efficiencies of different image segmentation methods in H&E and Olig2 stained images obtained from digital slides. An auto‐adjustable image analysis workflow was generated and compared with neuropathologists for p53 positivity quantification. Finally, the density of extracted features of the nuclei, p53 positivity quantification, and combined ATRX/age feature was used to generate a predictive model for 1p/19q codeletion in IDH‐mutant tumors. Results Information theory calculations can be performed on open access platforms and provide significant insight into linear and nonlinear associations between diagnostic biomarkers. Age, p53, and ATRX status have significant information for the diagnosis of IDH‐mutant tumors. The predictive models may facilitate the reduction of false‐positive 1p/19q codeletion by fluorescence in situ hybridization (FISH) testing. Conclusions We posit that this approach provides an improvement on the cIMPACT‐NOW workflow recommendations for IDH‐mutant tumors and a framework for future resource and testing allocation. Different clustering patterns with clinical, histologic, immunohistochemical, and molecular information on the brain cancer population simulation and information gain in the glioma simulation model for clinical decision‐making. Dimensionality reduction by principal component analysis is shown in A1–A4, and by t‐stochastic neighbor embedding in B1–B4, with the features delineated on the top of each graph. Each color represents a unique diagnosis in the WHO classification scheme. (A1 and B1) Dimensionality reduction with clinical features alone demonstrates only a few visible clusters. (A2 and B2) Incorporating clinical history with histology generates the commencement of clear layering in PCA and discrete clusters with t‐SNE. (A3 and B3) Inclusion of immunohistochemical data improves the capacity of discerning clusters. (A4 and B4) The additional molecular features does not significantly improve the clustering. (C) Individual information gains with all clinical, histologic, immunohistochemical, and molecular features in the glioma simulation model. Age, site, and Ki67 are the features that have the most amount of necessary information for the diagnosis. (D) Information gains with clinical, histologic, immunohistochemical, and molecular information. Histology provides most of the necessary information for the diagnosis. Combining the clinical data with histology and immunohistochemistry provides more than 95% of the necessary information, whereas adding molecular data provides minimal information gain. (E) IDH1/2‐mutated tumors were subsetted, and the mutual information of the features on the X‐axis was quantified as % information on the Y‐axis. The conditional information function call was called on data the 1p19q status.
Journal Article
Glioblastoma with Unusual Features: Presentation with Intracerebral Hematoma, Diagnosis with CT Perfusion and Subsequent Cerebral Venous Sinus Thrombosis with Resultant New Hemorrhage
by
Danyeli, Ayça Erşen
,
Özer, Ercan
,
Bülbül, Hande Melike
in
Blood
,
Blood-brain barrier
,
Brain cancer
2023
During the course of primary malignant brain tumors, there is an increased tendency for both intracerebral hemorrhage and venous sinus thrombosis.
A 63-year-old man presented with a headache, and a brain computed tomography (CT) scan showed a hematoma in the right occipital lobe. Magnetic resonance imaging (MRI) revealed almost complete rim enhancement, and CT perfusion showed increased cerebral blood volume values. A new bleeding focus and a thrombus extending from the superior sagittal sinus to the cortical vein were seen on CT and MRI scans performed due to the headache that developed the day before surgery. After surgical evacuation of the hematoma, a giant cell glioblastoma diagnosis was made as a result of pathological examination of the lesion.
In challenging cases like this, perfusion techniques are useful. Cerebral venous sinus thrombosis should also be kept in mind during the perioperative and postoperative periods to avoid complications.
Journal Article
A pediatric bithalamic high grade glioma with concomitant H3K27M and EGFR mutations
2022
Background. Despite many treatment approaches, survival rates in high grade glial tumors are still not at the desired level. One of the cause of this failure might be that although having similar histologic features, they may display different biological behaviors depending on molecular heterogeneity. Case. A 10-year-old girl presented with sudden onset left sided hemiparesis, headache, and ataxia. Physical examination was normal except for left sided hemiparesis and ataxia. A hyperintense mass lesion involving the bilateral thalamus was detected in the axial T2-weighted and coronal FLAIR sequences on brain MRI. There was no enhancement in axial T1-weighted contrast-enhanced sequences. Due to the size and location of the tumor, the patient was considered inoperable. Intensity modulated radiotherapy was intended for curative treatment to the patient because the radiological findings suggested a low-grade glial tumor. Tumor was unresponsive to radiotherapy but biopsy could be performed. The histopathological examination revealed a diffuse glial tumor with increased cellularity, mild nuclear atypia and rare mitosis. Due to the infiltrative pattern of the tumor, it was accepted as a high grade diffuse glial tumor. A chemotherapy protocol including cisplatin and etoposide in the first cycle, vincristine and cyclophosphamide in the second cycle, and carboplatin and vincristine in the third cycle were instituted to the patient. After the third cycle of chemotherapy, the tumor progressed radiologically. H3.1 K27M c.83A > T (HIST1H3C p.Lys28Met), ATRX c.2169_2170del (p.Glu723AspfsTer9), TP53 c.338T > C (p.Phe113Ser), and EGFR c.2300_2308dup (p.Ala767_va1769dup) were detected in the genetic assessment of tumor tissue. The patient`s treatment was changed to vincristine, temozolomide, and irinotecan. Unfortunately, MRI showed progression after three cycles of second-line chemotherapy. The patient`s family refused any further treatment, and the patient died with progressive disease in a short time. Conclusions. EGFR mutation along with H3.1 K27M mutation is extremely rare in children to our knowledge. It should be kept in mind that if there is a possibility of targeted therapy, there may be a treatment option in this malignant disease with a poor prognosis.
Journal Article