Abdurrahman Işıkdoğan

Dr. Abdurrahman Işıkdoğan

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2003
Verified
Journal Article
Closed access
MDMehmet Dursun
Mehmet Dursun
MYMehmet Yaldiz
Mehmet Yaldiz
AIAbdurrahman Işıkdoğan
Abdurrahman Işıkdoğan
GYGülşen Yilmaz
Gülşen Yilmaz
FCFikri Canoruç
Fikri Canoruç
SYSerif Yilmaz
Serif Yilmaz
Primary squamous cell carcinoma of the stomach is extremely rare. To date, only 80 cases have been reported. A 65-year-old man with complaints of epigastric pain and cachexia for the past year is presented. He had a tumour with infiltration of the corpus and antrum of the stomach. The tumour was unresectable, and the patient died within 3 months.

1 January 2003 in Leukemia & Lymphoma
Verified
Journal Article
Closed access
AIAbdurrahman Işıkdoğan
Abdurrahman Işıkdoğan
MAMEHMET ORHAN AYYILDIZ
MEHMET ORHAN AYYILDIZ
MDMehmet Dursun
Mehmet Dursun
NTNaci Tiftik
Naci Tiftik
SBSabri Batun
Sabri Batun
EMEkrem Muftuoglu
Ekrem Muftuoglu
Hepatitis C virus (HCV) has been associated with several extrahepatic disorders including mixed cryoglobulinemia (MC), autoimmune thyroiditis, Sjogren's syndrome. Such associations have led to the suggestion that HCV may participate in the development of various immunmediated disorders. Recently, it has been hypothesised that HCV might act as a trigger for the development of monoclonal B-cell disorders such as non-Hodgkin's lymphoma (NHL). Discordant data have been reported in different geographic regions of the world. The aim of this prospective case-control study was to detect the prevalence of HCV in patients with NHL in southeastern Anatolia region of Turkey. In this study, HCV antibody prevalence and cryoglobulinemia were investigated in 119 patients with histologically diagnosed NHL. The control group consisted of 117 patients who visited the outpatient clinic of internal medicine. None of the patients had HCV antibody positive (0%) with the enzyme immunoassay and reverse transcriptase polymerase chain reaction (RT-PCR). One of the control patients had positive HCV antibody (0.9%). Our data does not support the association between HCV infection and NHL in southeastern Anatolia region of Turkey.

30 March 2020 in BMC Cancer
Verified
Journal Article
Open access
PDF file
SYSuayib Yalcin
Suayib Yalcin
FDFaysal Dane
Faysal Dane
BOBerna Oksuzoglu
Berna Oksuzoglu
NONuriye Yildirim Ozdemir
Nuriye Yildirim Ozdemir
AIAbdurrahman Işıkdoğan
Abdurrahman Işıkdoğan
SKSaadettin Kilickap
Saadettin Kilickap
Background: Combination of gemcitabine and nab-paclitaxel has superior clinical efficacy than gemcitabine alone. Nevertheless, health-related quality of life. (QoL) associated with this combination therapy when administered at first-line in advanced pancreatic adenocarcinoma is unknown. Methods: A total of 125 patients were randomized to combination therapy (1000 mg/m2 gemcitabine + 125 mg/m2 nab-paclitaxel) and single-agent gemcitabine (1000 mg/m2) arms to take treatment weekly for 7 of 8 weeks, and following 3 of 4 weeks, until progression or severe toxicity. Primary endpoints were three-months of definitive deterioration free percent of patients, and QoL. Results: Overall QoL analyses showed that 34 and 58.3% of cases in gemcitabine and gemcitabine+nab-P arms had no deterioration in 3rd month QoL scores (p = 0.018). These proportions were 27.3 and 36.6% in 6th month assessments, respectively (p = 0.357). Median overall survivals in combination and single-agent arms were 9.92 months and 5.95 months, respectively (HR: 0.64, 95% CI: 0.42–0.86, p = 0.038). Median progression free survivals in these treatment arms were 6.28 and 3.22 months, respectively (HR: 0.58, 95% CI: 0.39–0.87, p = 0.008). Median time-to-deterioration were 5.36 vs 3.68 months, and objective response rates were 37.1% vs 23.7% (p = 0.009), respectively in combination and single-agent arms. Conclusions: Combination therapy with gemcitabine + nab-paclitaxel had better overall and progression-free survival than gemcitabine alone. Also, combination therapy showed increased response rate without toxicity or deteriorated QoL. Combination treatment with gemcitabine and nab-paclitaxel may provide significant benefit for advanced pancreatic cancer. Trial registration: This study has been registered in ClinicalTrials.gov as NCT03807999 on January 8, 2019 (retrospectively registered).

18 March 2013 in Oncology Research and Treatment
Verified
Journal Article
Closed access
MKMuhammet Ali Kaplan
Muhammet Ali Kaplan
AIAli Inal
Ali Inal
MKMehmet Kucukoner
Mehmet Kucukoner
ZUZuhat Urakci
Zuhat Urakci
FEFaysal Ekici
Faysal Ekici
AIAbdurrahman Işıkdoğan
Abdurrahman Işıkdoğan
Aim: The aim of the current study was to evaluate whether early detection of brain metastases (BMs) could improve survival outcomes in human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients. Material and Methods: HER2-positive breast cancer patients without BMs who had no neurological symptoms within 12 months from diagnosis or relapse time of the disease were included in the study. The patients were distributed into 2 groups: Group 1 comprised patients without metastases; group 2 comprised patients with metastases. The symptomatic historic control group with BMs was defined retrospectively for survival comparisons. Results: 55 (57.3%) and 41 (42.7%) patients were in groups 1 and 2, respectively. 11 of the 96 patients (11.5%) had occult BMs, and 9 of them were in group 2 whereas only 2 patients were in group 1 (22% vs. 3.6%, respectively; p = 0.008). While the median survival times from the first metastasis (28.7 vs. 22.5 months, respectively; p = 0.561) and BM (6.8 vs. 6.1 months, respectively; p = 0.511) were similar, cerebral death was numerically different (16.7% vs. 46.3%; p = 0.221) between asymptomatic (n = 9) and symptomatic patients (n = 53). Conclusions: BMs were detected very rarely in asymptomatic, non-metastatic HER2-positive breast cancer patients compared with asymptomatic, metastatic patients. Furthermore, although early detection of BMs decreases the cerebral death rate, it does not prolong the survival rate in metastatic patients.

22 June 2012 in Medical Oncology
Verified
Journal Article
Closed access
PDF file
EEEmin Tamer Elkiran
Emin Tamer Elkiran
AGAnatolian Society of Medical Oncology Group
Anatolian Society of Medical Oncology Group
MKMuhammet Ali Kaplan
Muhammet Ali Kaplan
ASAlper Sevinc
Alper Sevinc
SASercan Aksoy
Sercan Aksoy
SBSuleyman Buyukberber
Suleyman Buyukberber

10 April 2025 in Medicina
Verified
Journal Article
Open access
PDF file
NINurullah Ilhan
Nurullah Ilhan
FDFaysal Dane
Faysal Dane
EGERDEM GOKER
ERDEM GOKER
KUKazım Uygun
Kazım Uygun
BOBulent Orhan
Bulent Orhan
MGMahmut Gumus
Mahmut Gumus
Background and Objectives: KRAS genes are among the most prominent oncogenes that trigger tumor formation in colorectal cancer (CRC) and serve as predictive biomarkers for resistance to anti-EGFR therapies in metastatic colorectal cancer (mCRC) patients. However, the prevalence and mutation spectrum of the KRAS gene family in mCRC patients in Turkey have not been sufficiently analyzed. This study investigates the frequency and distribution of mutations in the KRAS gene family across different regions of Turkey and examines gender-related variations. Materials and Methods: This multicenter observational study included 2458 histologically confirmed mCRC patients collected from 52 centers across Turkey. In a central laboratory, KRAS mutations in codons 12 and 13 were analyzed using polymerase chain reaction (PCR). Statistical analyses were performed using chi-square tests and Monte Carlo simulations, with a significance threshold set at p < 0.05. Results: Depending on the region, KRAS mutations were detected in 45% of patients, ranging from 39.6% to 47.5%. The mutation rate was significantly higher in female patients (48.8%) compared to male patients (42.6%) (p = 0.002). Codon 12 mutations were more frequent than codon 13 mutations. G12D, G12V, and G13D mutations accounted for 80% of all detected mutations. The G12V mutation was prevalent in female patients (p = 0.007). Based on region, mutation diversity was similar, and no statistically significant difference was found (p > 0.05). Conclusions: This large-scale, multicenter study provides the most comprehensive dataset of KRAS mutations in mCRC patients in Turkey. This study revealed regional trends, as well as gender differences. The findings highlight the importance of routine KRAS genotyping in guiding personalized treatment strategies, especially regarding candidate selection for anti-EGFR therapies. Further research is required to elucidate the prognostic and therapeutic implications of specific KRAS mutations.