FDG PET/CT in pancreatic cancer staging and management: A retrospective study.

Abstract

464 Background: FDG PET/CT scan (PET) has been approved by Cancer Care Ontario since 2011 for pancreatic cancer patients who have potentially resectable disease. A recent prospective study supported the use of PET in patients with a pancreatic mass and showed improved staging accuracy. Herein, we reviewed the outcomes of PET in the disease staging and management of patients with pancreatic mass at a single academic center. Methods: We collected demographics, CA 19-9 level, CT, MRI and PET results of patients with suspicious pancreas mass followed at Sunnybrook Health Sciences Centre from April to August 2011. We reviewed disease staging after CT/MRI and clinical management decision after PET result. We excluded patients with proven non-primary adenocarcinoma of the pancreas from the analysis. Results: In this cohort, 58 patients had PET scans. 14 patients with non-primary adenocarcinoma of the pancreas were excluded. From 44 patients analyzed, 61% of them were females, median age 70, 19 patients had biliary obstruction with biliary drain, CA 19.9 was elevated preoperatively in 27 patients (level above 1400 was seen in 37% of 44 patients), pancreatic mass median SUV = 4.8 and 7 patients had SUV < 2.5 with no FDG avid at the pancreas mass (both biopsy proven). Ten patients were discovered to have metastatic disease on PET. PET results were discordant with the CT/MRI disease staging in 34% of cases. PET revealed metastatic disease in 7 patients with prior CT or MRI considered to be negative for metastasis. PET showed localized disease in 8 patients with suspicious metastasis on CT or MRI. However, none of the patients underwent pancreatic resection. Clinical management was changed after PET results in 80% of patients with discordant PET and CT/MRI results. Conclusions: In this single-centre retrospective analysis, PET results changed the metastatic disease status depicted by CT or MRI in 34% of patients and clinical management was guided by PET results for the majority of those patients. This supports the use of PET as a tool to guide staging and treatment of pancreas cancer.