title: Assessment of cell proliferation in renal cell carcinoma using dual-phase18F-fluorodeoxyglucose PET/CT.
abstract: The present study aimed to examine the association between18F-fluorodeoxyglucose (18F-FDG) uptake and cell proliferation markers; in addition, the correlation between18F-FDG uptake and biological characteristic in patients with renal cell carcinoma (RCC) was investigated using dual-phase18F-FDG-positron emission tomography/computed tomography (PET/CT). Dual-phase18F-FDG PET/CT was performed on 31 RCC patients and the maximum standardized uptake values at 1 h (SUV1) and 2 h (SUV2) as well as the retention index (RI; %) in the primary tumors were calculated. Monoclonal antibodies for Ki-67, minichromosome maintenance 2 (MCM2) and topoisomerase II α (topo II α) were used to assess the expression levels of their respective proteins in excised tumor tissue using immunohistochemistry. The results demonstrated that RI and SUV2 in patients with Stage I/II + grade 1 (G1) RCC were significantly decreased compared with all patients with other stages/grades (RI, P=0.0065; SUV2, P=0.043); in addition, significantly increased uptake and RI were detected in patients with metastases compared with patients without metastases (SUV1, P=0.029; SUV2, P=0.0003; RI, P<0.001). All proliferation markers significantly correlated with RI (Ki-67, r=0.501, P=0.004; MCM2, r=0.359, P=0.047; topo II α, r=0.402, P=0.024), while SUV1 and SUV2 correlated with Ki-67 only. In conclusion, the results of the present study demonstrated that dual-phase18F-FDG-PET/CT was more useful for predicting cell proliferation in RCC compared with single-phase imaging alone. However, follow-ups are required in order to determine whether dual-phase18F-FDG-PET/CT provides independent prognostic information.
authors.affiliation: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Rei
authors.initials: R
authors.lastname: Onishi
authors.affiliation: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan ; Clinical Research Division, Research Center for Innovative Cancer Therapy, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Noguchi
authors.affiliation: Division of Nuclear Medicine, PET Center and Department of Radiology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Hayato
authors.initials: H
authors.lastname: Kaida
authors.affiliation: Department of Pathology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Fukuko
authors.initials: F
authors.lastname: Moriya
authors.affiliation: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Chikui
authors.affiliation: Division of Nuclear Medicine, PET Center and Department of Radiology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kurata
authors.affiliation: Department of Pathology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kawahara
authors.affiliation: Department of Pathology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kage
authors.affiliation: Division of Nuclear Medicine, PET Center and Department of Radiology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Ishibashi
authors.affiliation: Department of Urology, Kurume University School of Medicine, Kurume, Fukuoka 830-0011, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Matsuoka
keywords: 18F-fluorodeoxyglucose; Ki-67; cell proliferation; minichromosome maintenance 2; positron emission tomography/computed tomography; renal cell carcinoma; topoisomerase IIα