THE VALUE OF (18)FLUOR-DEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY/COMPUTED TOMOGRAPHY (18FDG-PET/CT) IN RESECTABLE PANCREATIC CANCER: A PROSPECTIVE STUDY

Background and aim : Whole-body (18)fluor-deoxyglucose positron emission tomography/computed tomography (PET/CT) has emerged as a promising diagnostic modality in different tumors. The role and the utility of (18)FDG-PET/CT in resectable pancreatic cancer is debated. Aim of the present work was to assess prospectively the value of (18)FDG-PET/CT in addition to conventional imaging as a staging modality in candidates for resection of resectable pancreatic cancer. Secondary aim is to correlate (18)FDG-PET/CT results with tumor-recurrence after resection. Material and methods : Whole-body (18)FDG-PET/CT was performed in 72 patients with pancreatic ductal adenocarcinoma who were judged resectable at high-resolution imaging. Neoadjuvant therapy was performed in the 14% of cases. Maximum standardized uptake value (SUVmax) was evaluated 60 minutes after FDG injection. PET/TC was considered "positive" for pancreatic cancer when SUV > 3. Results : 8/72 (11%) patients were spared unwarranted resection since (18)FDG-PET/CT detected synchronous advanced lung cancer (n=1) or metastatic disease (n=7). Median CA 19.9 was 48.8 U/mL for the entire cohort and 292 U/mL for seven patients with metastases (p=0.112). In other two patients (18)FDG-PET/CT identified one colon carcinoma and a thoracic neurinoma. 15/72 (21%) patients had low metabolic activity (SUVmax<3), and 60% of these patients had undergone neoadjuvant treatment (p=0.0001). At laparotomy 3/64 (5%) patients did not undergo resection because of locally-advanced (n=1) or metastatic disease (n=2). 61 patients underwent pancreatic resections with curative intent. N1 rate was 77%, with a median of 33 resected nodes. In 8/61 (13%) patients (18)FDG-PET/CT identified metastatic lymph nodes that required an extension of lymphadenectomy. Sensitivity and specificity of (18)FDG-PET/CT for the detection of metastatic disease were 78% and 100%, respectively. Median follow-up for resected patients was 10 months and 53% of them developed recurrence. No significant correlation between SUVmax values and disease-free survival was found. Conclusions : (18)FDG-PET/CT findings resulted in changes of therapeutic management/operative procedures in one third of patients. (18)FDG-PET/CT improves staging of patients with resectable pancreatic cancer. Neoadjuvant treatment is significantly associated with low metabolic activity limiting the value of (18)FDG-PET/CT in this setting.