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Öğe Awareness and perceptions of clinical trials in patients with cancer and their families in Turkey(Lippincott Williams & Wilkins, 2023) Kubilay, Pinar; Erol, Cihan; Kahraman, Seda; Tacar, Seher Yildiz; Ozcan, Erkan; Basal, Fatma Bugdayci; Kose, Fatih[Abstract Not Available]Öğe Comparison of real-life data from patients with NGS panel negative and KRAS mutation positive metastatic lung adenocarcinoma(Sage Publications Ltd, 2022) Gokyer, Ali; Kucukarda, Ahmet; Kostek, Osman; Gokmen, Ivo; Ozcan, Erkan; Sayin, Sezin; Tastekin, EbruObjective: To evaluate clinical and demographic characteristics and the results of cytotoxic treatments of KRAS(G12C), KRAS(other), and next-generation sequencing (NGS) panel negative patients. Methods: NGS data of 1264 patients with non-small cell lung cancer were retrospectively evaluated. Among these patients, the mutation distributions of 1081 patients with metastatic lung adenocarcinoma were analyzed. A total of 150 patients with negative NGS panel or mutant KRAS followed up in our clinic were included. Clinical features, overall survival, first-line chemotherapy responses, and progression-free survival of NGS panel negative, KRAS(G12C), and KRAS(other) groups were compared. Results: In 1081 patients who underwent NGS from tumor tissue with the diagnosis of metastatic lung adenocarcinoma, 296 (27%) NGS panel negative and 276 (26%) KRAS mutant patients were detected. Among these patients, 150 patients whose data were available were 71 (47.3%) NGS panel negative, 54 (36%) KRAS(other), and 25 (16.7%) KRAS(G12C). Clinical features, brain metastasis, and first-line chemotherapy response were similar among groups. Bone metastases were detected more often in the NGS panel negative group (p = 0.03). The median follow-up was 8.4 months. Overall, 107 deaths had occurred at the time of analysis. There was no difference in overall survival (p = 0.56) or progression-free survival (p = 0.71) among NGS panel negative, KRAS(other), and KRAS(G12C) patients. Conclusion: There is no difference in overall survival, first-line chemotherapy response, or progression-free survival among patients with NGS panel negative, KRAS(G12C), or KRAS(other) metastatic lung adenocarcinoma. Bone metastases were observed more frequently in the NGS panel negative group.Öğe An experimental study: the effect of S. boulardii on abemaciclib-induced diarrhea(Tubitak Scientific & Technological Research Council Turkey, 2023) Cakcak, Ibrahim Ethem; Aytin, Yusuf Emre; Sayin, Sezin; Kucukarda, Ahmet; Gokyer, Ali; Gokmen, Ivo; Ozcan, ErkanBackground/aim: In our study, we aimed to investigate the protective effects of Saccharomyces boulardii on abemaciclib-induced diarrhea model, which is a commonly used drug in breast cancer. Materials and methods: Thirty rats were divided into 3 groups as control (Group 1), abemaciclib (Group 2), and abemaciclib + Saccharomyces boulardii (Group 3) groups. The clinical status, body weight, and defecation status were monitored daily. At the end of the 15-day experiment period, the rats were killed with high-dose anesthesia and the resected small intestine segments were evaluated histopathologically. Lesions were classified according to thickening of the villus, inflammation and edema of mucosa and intraepithelial leukocyte accumulation. Then, mean values of both crypt depths and villi thicknesses were calculated for each rat. Normal distribution assumption was controlled with the Shapiro-Wilk test. One-way analysis of variance for normally distributed variables in the comparisons of more than two independent groups and Kruskal-Wallis test for nonnormally distributed variables were used. The significance value was accepted as 0.05. Results: There was one death in Group 3, but none in the others. There were no findings of mucositis in Group I. There was mild diarrhea and weight loss in only one rat in Group 1. For the comparison of the severity of diarrhea (72.5%/39%) and weight loss (72.5%/45%), a decrease was found in Group 3 according to Group 2 (p < 0.01). Histopathological findings such as edema, inflammation, and intraepithelial leukocyte accumulation also showed a decrease in Group 3 compared to Group 2 (p < 0.01). Conclusion: Saccharomyces boulardii should be considered as a treatment option in abaemaciclib (chemotherapy)-induced diarrhea. Further comparative studies and in vivo human randomized controlled studies can be conducted in the future.Öğe Molecular Pattern and Clinical Implications of KRAS/NRAS and BRAF Mutations in Colorectal Cancer(Mdpi, 2023) Gokmen, Ivo; Tastekin, Ebru; Demir, Nazan; Ozcan, Erkan; Akgul, Fahri; Hacioglu, Muhammed Bekir; Erdogan, BulentThe aim of our study was to evaluate the incidence of KRAS/NRAS and BRAF mutations, analyze molecular patterns, and investigate associations with clinical parameters of these mutations in CRC KRAS/NRAS and BRAF mutations analyzed by next-generation sequencing. The detection rates of these mutations and patients' demographics were recorded and the relationship between them was evaluated using the chi-square test. KRAS mutation was detected in 332 of 694 patients, while the mutation rates in KRAS exons 2/3 and 4 were 39.6%/3.2% and 5%, respectively. The most common mutation pattern was KRAS G12D. Five atypical variants were detected: V14I in KRAS exon 2, A18D, Q22K and T50I in exon 3, and T148P in exon 4. NRAS mutation was detected in 29 (4.5%) patients. One atypical variant L80W was detected in NRAS exon 3. BRAF mutation was seen in 37 (5.3%) patients, with BRAF(V600E) (83.8%) being the most common mutation pattern. NRAS mutation was significantly more frequent in patients > 64 years of age, BRAF mutation in women, and NRAS/BRAF mutations in right colon tumors. Grouping BRAF mutations into BRAF(V600E) and BRAF(non-V600E) and their analysis according to specific tumor localizations showed that all four BRAF(non-V600E) mutations originated in the rectum. In our study, KRAS exon 2 and other RAS mutation rates were higher than in the literature, while the BRAF v.600E mutation rate was similar. NRAS and BRAF mutations were significantly more frequent in the right colon. BRAF mutation was more common in women and in the right colon.Öğe Patient preferences for use of archived biospecimens in Turkey(Lippincott Williams & Wilkins, 2023) Tolunay, Pinar Kubilay; Erol, Cihan; Kahraman, Seda; Tacar, Seher Yildiz; Ozcan, Erkan; Basal, Fatma Bugdayci; Kose, Fatih[Abstract Not Available]Öğe Prognostic Factors for Survival in Transverse Colon Cancers(Springer, 2022) Kucukarda, Ahmet; Gokyer, Ali; Sayin, Sezin; Gokmen, Ivo; Ozcan, Erkan; Kostek, Osman; Hacioglu, Muhammet BekirBackground Transverse colon cancer (TCC) is a rare condition that accounts for 10% of all colon cancers. TCC was accepted more likely right-sided colon cancers. We aimed to investigate whether TCC differs from other colon tumors by using clinical, pathological, and molecular prognostic factors known to be important in colon cancer and if it differs in its own anatomical structure. Patients and Methods We evaluated local and locally advanced TCC patients between 2007 and 2020 years for demographics data, symptoms, treatment status, and histopathological and molecular features. Results Overall, 107 TCC patients were included in this study. According to the molecular data analysis of 44, 35, and 23 patients for MSI, RAS, and BRAF status, respectively, 7 (15.9%) were MSI-H, 13 (37.1%) were RAS mutant, and 11 (47.8%) had BRAF V600E mutation. The median follow-up time was 31.5 months. Median disease-free survival (DFS) was 5.19 months, and median OS was 88.3 months for the whole study population. The tumor stage was the most significant prognostic factor for DFS and OS. Although BRAF mutation was not a significant marker for DFS, it was an independent prognostic marker for OS (HR 3.90 95% CI 1.42-10.7). There were no statistically significant differences between proximal two-thirds and distal one-third tumor location. Conclusion TCC has molecular features and prognostic factors more likely RCC and no differences between proximal and distal sub-parts. BRAF V600E mutation status is an independent predictor of survival even in the early stages of TCC.Öğe Prognostic nutritional index and its dynamics after curative treatment are independent prognostic factors on survival in non-metastatic nasopharyngeal carcinoma(Springer, 2022) Kucukarda, Ahmet; Erdogan, Bulent; Gokyer, Ali; Sayin, Sezin; Gokmen, Ivo; Ozcan, Erkan; Hacioglu, Muhammet BekirPurpose We aimed to identify the prognostic and predictive values of post-treatment prognostic nutritional index (PNI) and PNI dynamics in nasopharyngeal cancer patients (NPC) in this study. Methods One hundred seven non-metastatic NPC patients were included. PNI was calculated by using the following formula: [10 x serum albumin value (gr/dL)] + [0.005 x total lymphocyte count (per mm3)]. ROC analysis was used for determining prognostic PNI values and univariate and multivariate statistical analyses for prognostic characterization of PNI. Results The statistically significant cut-off values for pre- and post-treatment PNI were 50.65 and 44.75, respectively. Of the pre-treatment PNI analysis, PNI <= 50.65 group had shorter loco-regional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), and overall survival (OS). Furthermore, for post-treatment PNI analysis, PNI <= 44.75 group had shorter LRRFS and OS. In univariate analysis, only pre-treatment PNI was associated with LRRFS and DMFS, while pre- and post-treatment PNI were both associated with OS. In multivariate analysis, both PNI were independent prognostic markers for OS. In the combined analysis, pre- and post-treatment PNI, differences between the groups were statistically significant, and the PNI dynamics was an independent prognostic indicator for OS. Conclusion PNI is a useful, independent prognostic marker for non-metastatic NPC patients. It is used for either pre- or post-treatment patients. Furthermore, changes in pre-treatment PNI value after curative treatment is a significant indicator for OS.Öğe Recurrent delayed immune-related pneumonitis after immune-checkpoint inhibitor therapy for advanced osteosarcoma(Future Medicine Ltd, 2022) Kucukarda, Ahmet; Gokmen, Ivo; Ozcan, Erkan; Peker, Pinar; Akgul, Fahri; Cicin, IrfanIntroduction: The case of a patient who developed recurrent delayed immune-related pneumonitis (checkpoint inhibitor pneumonitis [CIP]) after immune checkpoint inhibitor (ICI) therapy for advanced osteosarcoma treatment is presented. Case summary: A 25-year-old female patient with metastatic osteosarcoma was treated with atezolizumab. Grade 2 pneumonitis developed three times in the first two years. Treatment was discontinued after recovery from the last episode of pneumonitis, which was complicated with secondary spontaneous pneumothorax. 2 years after discontinuation of immunotherapy, the patient again developed CIP. Pneumonitis symptoms were regressed with oral steroid therapy during follow-up and a stable disease response continued. Conclusion: Immunotherapy can cause recurrent CIP at any time during the treatment period or after discontinuation of treatment. Plain language summary Immune checkpoint inhibitors have been used in many types of cancer because they cause prolonged tumor responses. However, new side effects associated with these drugs have been identified. Pneumonia of the lung tissue may occur and recur during the use of these drugs or after their discontinuation. Patients with newly developing pulmonary symptoms during follow-up should be carefully monitored for this side effect.Öğe The relationship between positivity for COVID-19 RT-PCR and symptoms, clinical findings, and mortality in Turkey(Taylor & Francis As, 2021) Ozcan, Erkan; Yavuzer, Serap; Borku Uysal, Betul; Islamoglu, Mehmet Sami; Ikitimur, Hande; Unal, Omer Faruk; Akpinar, Yunus EmreIntroduction: This study aimed to assess the correlation between nucleic acid amplification test (real-time reverse transcription-polymerase chain reaction, RT-PCR) positivity of patients presenting with suspected COVID-19 and pneumonic infiltration consistent with COVID-19-specific pneumonia diagnosis on thoracic computed tomography (CT), with symptoms, laboratory findings, and clinical progression. Methods: The study included 286 patients (female:male 131:155; mean age, 53.3 +/- 17.9 years) who were divided into two groups according to their RT-PCR test results. The symptoms, laboratory examinations, clinical findings, and thoracic CT imaging of the patients were evaluated. Results: While the physical examination, comorbidities, and total CT scores were similar between the groups, taste/smell abnormalities were observed more frequently in the PCR-positive group. The use of moxifloxacin, lopinavir/ritonavir, and tocilizumab was higher in the PCR-positive group (p = 0.016, p < 0.001, and p = 0.002, respectively). The duration of hospitalization, intensive care requirement, and mortality rate of the studied groups did not differ between the groups. Conclusions: Among patients presenting with suspected COVID-19 and pneumonic infiltration consistent with COVID-19 on thoracic CT, the symptoms, physical examination, total CT scores, duration of hospitalization, intensive care requirement, and mortality rate were similar between RT-PCR-positive and RT-PCR-negative patients. However, PCR-positive patients appeared to require more specific treatments.Öğe Relationship between prognostic nutritional index and neutrophil lymphocyte ratio with overall survival in patients with metastatic colorectal cancer receiving regorafenib(Wolters Kluwer Medknow Publications, 2023) Erdogan, Bulent; Ozcan, Erkan; Gokmen, Ivo; Gokyer, Ali; Kucukarda, Ahmet; Kostek, Osman; Hacioglu, Muhammet BekirAim: In this study, we aimed to analyze the effect of prognostic nutritional index and neutrophile lymphocyte ratio on the overall survival (OS) in patients treated with regorafenib. Materials and Methods: Metastatic colorectal cancer (CRC) patients who treated with regorafenib between 2016 and 2020 in a single center were evaluated retrospectively. ROC analysis was used for neutrophile lymphocyte ratio (NLR's) and prognostic nutritional index (PNI's) optimum cut-off value. The relationship between OS with PNI and NLR was investigated. Results: Fifty-two patient's data were analyzed. The median age was 57 years, 22 (41.5%) of the patients were female. The optimal cut-off value of PNI for OS was 45.7 according to ROC curve analysis. The median NLR value was accepted as 2.7. Median OS was 8.3 months. Patients who have high PNI value than 45.7 had longer OS (12.09 months vs. 6.31 months hazard ratio [HR]: 0.37 95% confidence interval [CI]: 0.19-0.73 P = 0.003) and there was a tendency for longer OS with low NLR value then median (12.05 months vs. 6.14 months HR: 0.54 95% CI: 0.29-1.23 P = 0.057). Primary tumor resected patients had longer OS than nonresected patients (12.05 months vs. 6.30 months HR: 0.34 95% CI: 0.17-0.66 P = 0.001). In multivariate analysis, high PNI value more than 45.7 (HR: 0.40 95% CI: 0.18-0.88 P = 0.02) and resection of the primary tumor (HR: 0.40 95% CI: 0.21-0.80 P = 0.01) were the only independent factors for longer OS. Conclusion: Metastatic CRC patients with high pretreatment PNI and primary tumor resected are more likely to have longer OS with regorafenib. PNI is more reliable index than NLR to predict OS in metastatic CRC patients treated with regorafenib.
