RT Journal Article SR Electronic T1 Ki-67 Immunostaining in Pancreatic Cancer and Chronic Active Pancreatitis: Does In Vivo FDG Uptake Correlate with Proliferative Activity? JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 721 OP 725 VO 42 IS 5 A1 Andreas C. Buck A1 Holger H. Schirrmeister A1 Carl-Albrecht Guhlmann A1 Christoph G. Diederichs A1 Changxian Shen A1 Inga Buchmann A1 Jens Kotzerke A1 Dieter Birk A1 Thorsten Mattfeldt A1 Sven N. Reske YR 2001 UL http://jnm.snmjournals.org/content/42/5/721.abstract AB PET with 18F-FDG has been shown to be useful in the detection and staging of pancreatic cancer. However, whether FDG uptake is dependent on proliferative activity is still unclear. The aim of this prospective study was to evaluate a probable correlation between FDG uptake and proliferative activity in benign and malignant pancreatic tumors. Methods: Our series consisted of 23 patients with pancreatic cancer and 9 patients with chronic active pancreatitis (CAP). FDG PET was performed within 2 wk before surgery, and standardized uptake values (SUVs) were calculated for benign and malignant pancreatic tumors. Patients were selected when focally increased FDG uptake in previously known pancreatic tumors was present. Proliferation fraction was measured in tissue specimens using the anti–Ki-67 antibody MIB-1. A computer-assisted imaging system was used for quantification of nuclear Ki-67 immunostaining. Immunohistochemical findings were correlated to SUVs. Results: Pancreatic cancer showed both intense nuclear staining of Ki-67 (39% ± 16%) and high FDG uptake (SUV = 3.6 ± 1.6). However, no significant correlation was found between in vivo FDG uptake and Ki-67 immunoreactivity (P = 0.65). By contrast, Ki-67 nuclear staining was significantly lower (3.8% ± 2.7%, P < 0.05) in CAP, whereas FDG uptake was in the same range as for pancreatic cancer (SUV = 3.5 ± 1.8). Conclusion: FDG uptake did not correlate with proliferative activity in pancreatic cancer. Proliferative activity was tenfold higher in malignant pancreatic tumors than in benign tumors associated with CAP, whereas FDG uptake in vivo did not differ significantly. Thus, a PET tracer indicating cellular proliferation should better differentiate between cancer and inflammatory lesions than do metabolic markers such as FDG.