ORIGINAL ARTICLE

The Evaluation of Malignancy Rate of Incidental Thyroid Nodules Detected by FDG-PET/CT
FDG-PET/BT ile Saptanan İnsidental Tiroid Nodüllerinin Malignite Oranının Değerlendirilmesi
Received Date : 17 Dec 2020
Accepted Date : 23 Mar 2021
Available Online : 31 Mar 2021
Doi: 10.25179/tjem.2020-80668 - Makale Dili: EN
Turk J Endocrinol Metab. 2021;25:142-150
Bu makale, CC BY-NC-SA altında lisanslanmış açık erişim bir makaledir.
ABSTRACT
Objective: 18F-fluorodeoxyglucose positron emission tomography/ computed tomography (FDG-PET/CT) is widely used in investigating and staging malignancies. Malignancy rate is high in thyroid incidentalomas detected by FDG-PET/CT. The objective of this study was to evaluate the malignancy rate of incidental thyroid nodules in patients who had undergone FDG-PET/CT scan. Material and Methods: The reports of 10,197 FDG-PET/CT scans performed between January 2014 and May 2019 were analyzed retrospectively. The patients with incidental thyroid nodules and who underwent fine-needle aspiration biopsy (FNAB) were included in this study. Patients were stratified into two groups: malignant and non-malignant, according to FNAB cytological results. The association between maximum standardized uptake (SUVmax) values, ultrasonography (USG) findings, and cytological results of the biopsied nodules were investigated. Results: A total of 80 patients were included in the study. Forty (50%) of the patients were females, and the mean age was 63.2±11.4 years. Evaluation of FNAB results of 13 (16.3%) showed their malignant status. Of the patients in the malignant group, seven (53.8%) were females (mean age, 60.6±11.8 years). No statistically significant difference between the groups with or without malignancy in terms of gender distribution and mean age (p=0.762, p=0.401, respectively) was observed. The SUVmax value of the malignant group was 15.7 (5.1-29.7) and of the non-malignant group was 4.4 (1.6- 24.1) (p<0.001). Conclusion: We found that the malignancy rate is high in patients with thyroid incidentaloma detected by FDG-PET/CT and those who underwent FNAB, confirming previous results in the literature. It is suggested to evaluate further thyroid incidentaloma cases with high SUVmax values.
ÖZET
Amaç: Malignitelerin araştırılması ve evrelemesinde, 18F-florodeoksiglukoz pozitron emisyon tomografisi/bilgisayarlı tomografi (FDGPET/ BT) yaygın olarak kullanılmaktadır. FDG-PET/BT ile tespit edilen tiroid insidentalomalarında, malignite oranı yüksektir. Bu çalışma ile FDG-PET/BT yapılan hastalarda saptanan insidental tiroid nodüllerinde malignite oranının değerlendirilmesi amaçlanmıştır. Gereç ve Yöntemler: Ocak 2014 ve Mayıs 2019 tarihleri arasında gerçekleştirilen 10.197 adet FDG-PET/BT çekiminin raporları, retrospektif olarak incelendi. İnsidental tiroid nodülü saptanıp, ince iğne aspirasyon biyopsisi (İİAB) yapılan hastalar çalışmaya dâhil edildi. Hastalar, İİAB sitoloji sonuçlarına göre malign ve malign olmayan şeklinde 2 gruba ayrıldı. Biyopsi yapılan nodüllerin maksimum standart uptake (SUVmaks) değerleri, ultrasonografi (USG) bulguları ve patoloji sonuçları arasındaki ilişki araştırıldı. Bulgular: Çalışmaya toplam 80 hasta dâhil edildi. Bu hastaların 40’ı (%50) kadın olup, yaş ortalaması 63,2±11,4 yıl olarak bulundu. On üç (%16,3) hastanın İİAB sonucu, malign olarak değerlendirildi. Malign olan gruptaki hastaların 7’si (%53,8) kadın olup, yaş ortalaması 60,6±11,8 olarak hesaplandı. Malign olan ve olmayan gruplar arasında, cinsiyet dağılımı ve yaş ortalaması açısından anlamlı fark yoktu (sırasıyla p=0,762; p=0,401). Malign olan grubun SUVmaks düzeyi 15,7 (5,1-29,7), malign olmayan grubun ise 4,4 (1,6-24,1) saptandı (p<0,001). Sonuç: FDGPET/ BT ile tespit edilen ve İİAB uygulanan tiroid insidentaloma olgularında malignite oranını, literatür ile benzer şekilde yüksek bulduk. SUVmaks değeri yüksek tiroid insidentaloma olgularına, ileri tetkik yapılması gerekmektedir.
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