Evaluation of PIV Score as a Predictor Biomarker for Pathologically Proven Intermediate-High Risk Gastric Gastrointestinal Stromal Tumors

G astrointestinal stromal tumors (GIST) constitutes 1-3% of all gastrointestinal cancers that seems as subepithelial neoplasms. [1]Gastric GIST are most common subtypes of these neoplasms and they represents 50-60% of GIST. [2,3] ording to NCCN (National Comprehensive Cancer Network) guidelines, diagnosis of gastric GIST, found as incidentally or after using imaging methods in semptomatic cases, are clarified by evaluation of histopathologic and immunohistochemistry results and sometimes by some molecular alterations if can be analysed. [4]Endoscopy with bi-opsy, computed tomography (CT), abdominal ultrasound, magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) with fine needle biopsy are among the imaging methods that helpful in diagnosis of GIST. [5]After diagnosis, surgical resection is the main treatment of choice in primary localized gastric GIST but tumors with size of less than 2 cm may be followed up or resected endoscopically. [6]stric GIST are known to be associated with better survival outcomes than other GIST. [7]Based on the characteristics of the primary tumor, the disease may differ in prognosis.Pa-Objectives: Pan-immune-inflammation value (PIV) score has been started to be used as a prognostic tool in cancer patients trendly in recent years.In this study, we aimed to evaluate the PIV score in patients with pathologically-proven intermediate-high risk gastric GIST to guide adjuvant therapy and to get better prognosis.Methods: Patients followed up by Medical Oncology clinic with a diagnosis of gastric GIST were evaluated retrospectively.Results: A total of 41 patients with a diagnosis of gastric GIST were examined.When the tumors were analyzed according to the AFIP prognostic model, 23 patients were identified as intermediate-high-risk tumors.According to the modified NIH model, intermediate-high risk tumors were noted in 26 patients.According to AFIP prognostic model, PIV scores were not different between risk groups (p=0.27).When the patients were classified according to modified NIH model, the platelet counts in patients with intermediate-high risk tumor were significanly higher than the other patients group (p=0.01).In addition, PIV scores were significantly higher in patients with intermediate-high risk tumor than other patients (p=0.03). Conclusion:This study displayed that PIV score can be useful as a risk predictor in patients with gastric GIST.Future prospective analysis are needed to support our results.