The value of {sup 18}F-FDG PET/CT and carbohydrate antigen 19-9 in predicting lymph node micrometastases of pancreatic cancer

Purpose: This study aimed to assess the value of {sup 18}F-FDG PET/CT and carbohydrate antigen 19-9 (CA 19-9) levels in predicting lymph node micrometastases in patients with pancreatic cancer. Patients and methods: A total of 160 patients with pancreatic carcinoma were included in the study from 2012 to 2017. All patients underwent surgical treatment and PET/CT scans as well as tests to measure CA 19-9 levels before surgery. The PET/CT scans were evaluated by 2 nuclear medicine physicians who were blinded to the clinical information and were compared to the postsurgical pathological findings. Logistic regression analysis was performed to determine the variables that could predict lymph node micrometastases. Receiver operating characteristic (ROC) curves were utilized to find the best cutoff value of the variables related to predicting lymph node micrometastases. Results: The maximum standardized uptake value (SUV{sub max}) of the primary tumor and CA 19-9 level were potent predictors for determining the lymph node status. The best SUV{sub max} and CA 19-9 cutoff values for predicting lymph node micrometastases were 7.05 (sensitivity = 71.2%, specificity = 76.6%) and 240.55 U/ml (sensitivity = 62.1%, specificity = 79.8%), respectively. Conclusion: Patients with pancreatic cancer with a tumor SUV{sub max} ≥ 7.05 or a CA 19-9 value ≥ 240.55 are likely to have lymph node micrometastases.