RESULTS OF POSITRON EMISSION TOMOGRAPHY W ITH FLUORINE-18-LABELED FLUORODEOXYGLUCOSE IN STAGING AND DIFFERENTIAL-DIAGNOSIS OF PANCREATIC-CANCER

Although the detection of pancreatic carcinoma has been considerably i mproved by recently developed imaging procedures, differential diagnos is between cancer and benign tumor masses, as well as lymph node stagi ng, is still difficult. In vivo evaluation of regional glucose metabol ism by means of positron emission tomography (PET) and fluorine-18-lab elled fluorodeoxyglucose (FDG) is a new approach utilizing metabolic i nstead of morphological tumor properties for diagnosis. Patients and m ethods: A total of 85 patients with suspected pancreatic carcinoma wer e investigated by FDG-PET prior to surgery. Static PET scans were eval uated visually as well as quantitatively, taking increased FDG uptake as a sign of malignancy. PET results were correlated with intraoperati ve findings and histopathology of surgical specimens. Results: Forty-s even out of 55 (85%) malignant tumors and 23 out of 30 (77%) benign le sions were correctly classified by PET, Lymph node metastases were pre sent in 31 patients, 19 of them (61%) positive in PET. In 7 our of 13 (54%) patients with liver metastases, PET detected hypermetabolic lesi ons. False-negative findings were mainly due to disturbance of glucose metabolism in diabetic patients, while most false-positive results co uld be attributed to acute inflammatory lesions in chronic pancreatiti s. Conclusions: Our results indicate that classification of pancreatic masses can be improved by use of FDG-PET which might lead to a reduct ion of unnecessary laparotomies in patients with benign or incurable d isease.