dded Value of 18 F-FDG PET/CT as a Molecular Imaging to Diagnose Biological Behavior of Hepatocellular Carcinoma

Document Type : Original Paper, Oncology

Author

Oncology Center, Faculty of Medicine, Sohag University, Egypt

Abstract

Aim of work: To evaluate the role of FDG-PET/CT as additive imaging tool to evaluating the aggressiveness and extent of the hepatocellular Carcinoma (HCC) and assessment of extra-hepatic metastatic spread. Patients and Methods: A retrospective analysis of 77 patients with suspicious liver lesion of HCC on ultrasonographic examination. All patients were subjected to Tri-phasic CT and 18 FDG PET/CT qualitatively and quantitatively with SUV max calculation. All patients had histo-pathological examination with assessment of different grades of HCC. None of them received chemotherapy or radiotherapy. Results: The studied patients were 65 males (84.4%) and 12 females (15.6%) with mean age of 55.269.69 years. Seventytwo patients proved to have HCC (54 patients had poorly differentiated tumors, 8 patients with moderate differentiation and 11 patients were well differentiated tumors) and 5 patients had only liver cirrhosis. Serum Alfa fetoprotein (AFP) level was recorded in 38 patients, it was (< 100 ng/ml) in 8 patients, (100-400 ng/ml) in 7 patients and > 400 ng/ml in 23 patients. Tri-phasic CT showed criteria of malignancy in 71 patients with false negative result in (92.2%) one patient with poorly differentiated tumor. PET/CT showed metabolic activity in 54/ out of 72 patients (70.1%), all positive PET/CT patients had poorly differentiated tumor. Mean SUV max of liver lesions was 5.51 ±4.1. And Mean SUV max of liver parenchyma was 2.35 ±0.6. Both Triphasic CT and PET/CT showed positive metastatic lymph nodes in 20 patients (27.8%). PET/CT was able to detect additional mediastinal lymph nodes metastases in two patients. Total extra hepatic metastases (lung, bone and adrenal) detected by PET/CT were 14 patients (19.4%) compared to only one patient with adrenal metastases detected by abdominal Tri-phasic CT. Sensitivity, Specificity and Accuracy of PET/CT were 75%, 100% and 76-6% compared to 98.6%, 100% and 98.7% for Tri-phasic CT, respectively. Conclusion: 18F-FDG PET has an additional role in the evaluation of biological behavior of HCC with more metabolically active lesions seen in poorly differentiated HCC and in detecting extra-hepatic metastases.

Keywords