Uptake Patterns of Untreated Primary Gastrointestinal Extranodal Lymphomas on Initial Staging [.sup.18]F-FDG PET/CT and Metabolic Tumor Parameters/Primer Ekstranodal Gastrointestinal Sistem Lenfomalannda Primer Evreleme [.sup.l8]F-FDG PET/BT'de Tutulum Paternleri ve Metabolik Tumor Parametreleri

• Published in: Molecular imaging and radionuclide therapy 2017-10, Vol.26 (3), p.83
• Main Authors: Alagoz, Engin, Okuyucu, Kursat, Ince, Semra, Kantarcioglu, Murat, Ozaydin, Sukru, Heper, Cumhur, Turker, Turker, Arslan, Nuri
• Format: Article
• Language: English
• Subjects: Care and treatment; Gastrointestinal system; Non-Hodgkin's lymphomas; PET imaging; Prognosis
• ISSN: 2146-1414
• DOI: 10.4274/mirt.48658

Objective: Non-Hodgkin's lymphomas arising from tissues other than primary lymphatic sites are classified as primary extranodal lymphomas (PEL). PELs of the gastrointestinal system (PGISL) originate from the lymphatic tissues within the gastrointestinal tract. The prognostic value of [.sup.18]F-FDG PET/CT in lymphomas is high in terms of both overall survival (OS) and disease-free survival (DFS). Our aim was to investigate the uptake patterns and properties of low-grade and high-grade PGISL on primary staging [.sup.18]F-FDG PET/CT, as well as the prognostic significance of metabolic tumor parameters in high grade PGISL. Methods: Thirty-nine patients with PGISL were enrolled in this retrospective cohort study between 2004-2015. Primary staging [.sup.18]F-FDG PET/CT have been performed and quantitative parameters of [SUV.sub.max], [SUV.sub.mean], metabolic tumor volume (MTV), total lesion glycolysis (TLG) have been calculated for all patients prior to treatment. Low-grade and high-grade PGISL were compared in terms of metabolic tumor parameters. Cox regression models were performed to determine factors that correlate with DFS in high-grade PGISL. Results: There were statistically significant differences between high-grade and low-grade PGISL in terms of [SUV.sub.max], [SUV.sub.mean], MTV, TLG, recurrence, mortality, DFS and OS. None of the potential risk factors (sex, age, site, [SUV.sub.max], [SUV.sub.mean], MTV, TLG) for recurrence and metastasis in high grade PGISL was identified as a risk factor on univariate and multivariate Cox regression analysis. Conclusion: Metabolic tumor parameters are not predictive markers in high-grade PGISL, especially in diffuse large B cell variant and primary gastric lymphoma. The first implications suggest they will not play a role in patient management. Keywords: [.sup.18]F-fluorodeoxyglucose positron emission tomography/computed tomography, metabolic tumor parameters, primary gastrointestinal lymphoma Amac: Primer lenfatik alanlar disindaki dokulardan kaynaklanan Non-Hodgkin lenfomalara primer ekstranodal lenfoma (PEL) denmektedir. Gastrointestinal sistemin PEL'i (PGISL) buradaki lenfatik dokulardan koken alir. [.sup.18]F-FDG PET/BT lenfomalarda genel ve hastaliksiz sagkalim acisindan yuksek prognostik degere sahiptir. Amacimiz dusuk grad ve yuksek grad PGISL'de primer evreleme [.sup.18]F-FDG PET/BT'de tutulum sekillerini, ozelliklerini, yuksek grad PGISL'de metabolik tumor parametrelerinin prognostik onemi ile birlikte