Objective: Prognosis of patients with pancreatic cancer is poor. Median survival from diagnosis without determining surgical treatment is 3-11 months, after surgical treatment between 13-20 months according to various studies. 5-year survival rate is below 5%. The only chance of cure remains a radical surgical resection. Early diagnosis and determining resectability of tumour is the most important objective in patients with pancreatic cancer. Aim of this work is to evaluate the benefits and define the role of 18F-FDG PET/CT in preoperative staging.
Material and methods: 195 patients (103 men, 92 women, mean age 66.7 year, range 32-88 years) with suspected pancreatic lesions underwent enhanced 18F-FDG PET/CT in the preoperative staging in addition to standard investigative methods (ultrasonography, contrast enhanced CT, EUS, EUS FNA). All PET/CT findings were compared with standard methods (CT, EUS, EUS FNA), with peroperative findings and definitive histology in surgical patients as the reference standards. Interpretation of the extent of the tumor defined by TNM classification. Limitations of the local resectability was advanced local stage (T4) and presence of distant metastases (M1).
Results: In 195 patients with suspected pancreatic lesions was pre-operatively performed PET/CT in the period 1/2007-3/2009. 153 patients with pancreatic cancer, of which 72 was not suitable for radical surgery because of local inoperability or a generalization of the disease. The sensitivity of PET/CT in the capture of primary lesions was 92.2%, specificity 90.5%. False negative findings in 12 patients, false-positive results occurred in 4 cases, positive predictive value (PPV) 97.2%, negative predictive value (NPV) 76.0%. In the assessment of regional lymph nodes sensitivity was 51.9%, specificity 58.3%, PPV 58.3%,NPV 51.9%. In detection of distant metastases PET/CT reached sensitivity 82.8%, specificity 97.8%, PPV 96.9%, NPV 87.0%. PET/CT found distant metastases in 12 patients, which standard methods failed to detect. Surgery was cancelled in 15 patients (15.6%) with potentially resectable tumour based on the performance of PET/CT findings and the management of treatment was changed.
Conclusion: PET/CT is highly sensitive and specific method suitable for preoperative staging of pancreatic cancer. It improves the selection of patients for surgery, who can benefit from and reduces the number of incorrectly indicated operations.