J Nucl Med 2002 Feb;43(2):173-80
Relationship between retention index in dual-phase (18)F-FDG PET, and
hexokinase-II and glucose transporter-1 expression in pancreatic cancer.
Higashi T, Saga T, Nakamoto Y, Ishimori T, Mamede MH, Wada M, Doi R, Hosotani R,
Imamura M, Konishi J.
Recently, some studies have shown that delayed scanning with (18)F-FDG PET may
help to differentiate malignant from benign pancreatic lesions. However, no
study has evaluated the relationship between temporal changes in (18)F-FDG
uptake and expression of hexokinase or glucose transporter. METHODS: Twenty-one
consecutive patients with pancreatic cancer were studied preoperatively by
dual-phase (18)F-FDG PET, performed 1 and 2 h after injection of (18)F-FDG. The
standardized uptake value (SUV) of the pancreatic cancer was determined, and the
retention index (RI) (%) was calculated by subtracting the SUV at 1 h (SUV1)
from the SUV at 2 h (SUV2) and dividing by SUV1. The percentages of cells
strongly expressing hexokinase type-II (HK-II) and glucose transporter-1
(GLUT-1) were scored on a 5-point scale (1 = 0%-20%, 2 = 20%-40%, 3 = 40%-60%, 4
= 60%-80%, 5 = 80%-100%) by visual analysis of immunohistochemical staining of
paraffin sections from the tumor specimens using anti-HK-II and anti-GLUT-1
antibody (HK-index and G-index, respectively). RESULTS: SUV2 (mean +/- SD, 5.7
+/- 2.6) was higher than SUV1 (5.1 +/- 2.1), with an RI of 8.5 +/- 11.0. Four
cases of cancer, in which SUV2 showed a decline from SUV1, showed a low HK-index
(1.8 +/- 1.1), whereas 4 cases with an RI of > or =20 and 13 cases with an
intermediate RI (0-20) showed significantly higher HK-indices (4.3 +/- 0.7 and
3.1 +/- 1.5, respectively; P < 0.05). RI showed a positive correlation with
HK-index, with an R(2) of 0.27 (P < 0.05), but no significant correlation
with the G-index. SUV1 showed no relationship with the HK-index but showed a
weak positive correlation with the G-index, with an R(2) of 0.05 (P = 0.055).
CONCLUSION: These preliminary findings suggest that the RI obtained from
dual-phase (18)F-FDG PET can predict HK-II expression and that the SUV (at 1 h)
has a positive correlation with GLUT-1 expression but not with HK-II expression.
