The role of 18F-FDG PET/CT in the evaluation of patients with cancer of unknown primary

Abstract

Purpose: The aim of this retrospective study is to investigate the efficacy of 18F-FDG PET/CT in detecting primary cancer in patients with cancer of unknown primary and to compare PET/CT results with histopathological results. Materials and Methods: The data of 134 patients who presented to our clinic with the diagnosis of malignancy with unknown primary and underwent 18F-FDG PET/CT scan were examined from the hospital information system. PET CT scans of 114 of these patients, whose histopathological examination was completed, were re-evaluated by two experienced nuclear medicine specialists. PET/CT results were compared with histopathological findings. Sensitivity, specificity and accuracy of 18F-FDG PET/CT were calculated. In this patient series, the ratio of the confirmed CUP was calculated. Results: A total of 114 patients (56 women, 58 men) aged 13-90 years were included in the study. The mean age of the patients was 60.53 ± 17.04 years. Histopathologically, 73 (64%) patients were malignant and 41/114 (36%) patients were benign. According to 18F-FDG PET/CT, 83 (73%) patients were evaluated as malignant and 31 (27%) patients as benign or primary or metastatic. 18F-FDG PET/CT was able to accurately detect primary focus in 65 (89%) of 73 patients with histopathologically confirmed malignancy. 18F-FDG PET / CT could not identify the primary tumor site in 8 (11%) of 73 patients. Two of these eight patients were plasma cell myeloma, one was multible myeloma and one patient was lymphoma. Therefore, 4 (6%) patients were accepted as confirmed cancer of unknown primary. Overall, the diagnostic accuracy was found to be 78%, sensitivity 89%, specificity %56%,positive predictive value %78.5, negative predictive value%74. Conclusion: 18F-FDG PET/CT is highly successful in determining the primary cancer focus in patients with CUP due to its full body scanning advantage and high sensitivity.

Keywords

• cancers of unknown primary,fluorodeoxyglucose

Primeri bilinmeyen maligniteli hastaların değerlendirilmesinde 18F-FDG PET/BT’nin rolü

Abstract

Amaç: Bu retrospektif çalışmanın amacı, 18F-FDG PET/BT'nin primeri bilinmeyen kanserli hastalarda primer kanseri saptamadaki etkinliğini araştırmak ve PET/BT sonuçlarını histopatolojik sonuçlarla karşılaştırmaktır. Gereç ve Yöntem: Kliniğimize primeri bilinmeyen malignite öntanısıyla başvuran ve 18F-FDG PET/BT taraması yapılan 134 hastanın bilgileri hastane bilgi sisteminden incelendi. Bu hastalardan histopatolojik incelemesi tamamlanmış olan 114 tanesinin PET/BT taramaları iki deneyimli nükleer tıp uzmanı tarafından yeniden değerlendirildi. PET/BT sonuçları histopatolojik bulgularla karşılaştırıldı. 18F-FDG PET/BT’ nin sensitivite, spesifite ve doğruluk oranları hesaplandı. Bu hasta serisinde doğrulanmış primeri bilinmeyen kanser oranı hesaplandı. Bulgular: Çalışmamıza 56 kadın, 58 erkekten oluşan, yaşları 13-90 arasında 114 hasta dahil edildi. Hastaların ortalama yaşı: 60,53±17,04 yıl idi. Histopatolojik olarak 73 (%64) hasta malign, 41 (%36) hasta benign idi. 18F-FDG PET/BT’ye göre primer veya metastatik olarak toplam 83(%73) hasta malign, 31(%27) hasta benign olarak değerlendirildi. 18F-FDG PET/BT histopatolojik olarak malignitesi kanıtlanmış 73 hastanın 65’inde(%89) primer odağı doğru tespit edebildi. 18F-FDG PET/BT, 73 hastanın 8’ inde (% 11) primer tümör bölgesini tanımlayamadı. Bu sekiz hastanın ikisi plazma hücreli myelom, biri multible myelom ve bir hasta lenfoma idi. Bu nedenle 4(%6) hasta doğrulanmış primeri bilinmeyen kanser olarak kabul edildi. Genel olarak, tanısal doğruluk %78, duyarlılık%89, özgüllük%56, pozitif öngörü değeri% 78,5, negatif öngörü değeri% 74 olarak bulundu. Sonuç: 18F-FDG PET/BT primeri bilinmeyen malignite hastalarında tüm vücut tarama avantajı ve sensitivitesinin yüksek olması nedeniyle primer kanser odağını belirlemede oldukça başarılıdır.

Keywords

• Primeri bilinmeyen kanser,florodeoksiglukoz,pozitron emisyon tomografisi

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