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    Computed tomography texture analysis in patients with gastric cancer: a quantitative imaging biomarker for preoperative evaluation before neoadjuvant chemotherapy treatment
    (Springer, 2020) Yardimci, Aytul Hande; Sel, Ipek; Bektas, Ceyda Turan; Yarikkaya, Enver; Dursun, Nevra; Bektas, Hasan; Afsar, Cigdem Usul
    Purpose The aim of the study is to explore the role of computed tomography texture analysis (CT-TA) for predicting clinical T and N stages and tumor grade before neoadjuvant chemotherapy treatment in gastric cancer (GC) patients during the preoperative period. Materials and methods CT images of 114 patients with GC were included in this retrospective study. Following pre-processing steps, textural features were extracted using MaZda software in the portal venous phase. We evaluated and analyzed texture features of six principal categories for differentiating between T stages (T1,2 vs T3,4), N stages (N+ vs N-) and grades (low-intermediate vs. high). Classification was performed based on texture parameters with high model coefficients in linear discriminant analysis (LDA). Results Dimension-reduction steps yielded five textural features for T stage, three for N stage and two for tumor grade. The discriminatory capacities of T stage, N stage and tumor grade were 90.4%, 81.6% and 64.5%, respectively, when LDA algorithm was employed. Conclusion CT-TA yields potentially useful imaging biomarkers for predicting the T and N stages of patients with GC and can be used for preoperative evaluation before neoadjuvant treatment planning.
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    Öğe
    ROLE OF INSULIN-LIKE GROWTH FACTOR 1 (IGF-1) AND INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN-3 (IGFBP-3) IN THE DIAGNOSIS OF PANCREATIC ADENOCARCINOMA AND MONITORING TREATMENT RESPONSE
    (Carbone Editore, 2019) Bademler, Suleyman; Ucuncu, Whammed Zubeyr; Sari, Murat; Yasasever, Ceren Tilgen; Afsar, Cigdem Usul; Tastekin, Didem
    Purpose: Pancreatic cancer occurs rarely in humans, and it is one of the most fatal five cancer types with very poor prognosis. Early diagnosis of pancreatic cancer is difficult due to late presentation of symptoms. The purpose of our study was to evaluate the utility of IGFBP-3 and IGF-1 in early diagnosis of pancreatic cancer and in monitoring treatment response and contribute to the studies conducted in this regard. Methods: The study included 108 subjects, 54 of who were diagnosed with and followed-up for pancreatic cancer and 54 were healthy subjects. The results were compared between the two groups. The study was approved by the Istanbul Faculty of Medicine Ethics Committee. Results: The mean age of the patients included in the study was 54.42 years. IGF-1 levels and IGFBP-3 levels were significantly lower in pancreatic cancer patients than in the control group (respectively p = 0.002, 0.004). There was no difference between IGF-1 and IGFBP-3 levels in patients with distant metastasis (p > 0.05). IGF- 1 levels were significantly higher in patients who responded to chemotherapy than in those who did not respond to chemotherapy (p = 0.03). Conclusions: In our study, we observed that IGF-1 and IGHIP-3 levels can be used for the diagnosis of patients with pancreatic cancer and evaluation of treatment response and prognosis, and there is no significant difference in serum levels according to age, presence of distant metastasis, and gender.