FDG uptake, glucose transporter type 1, and Ki-67 expressions in non-small-cell lung cancer: Correlations and prognostic values

Abstract 

Purpose

FDG uptake mediated by glucose transporter type 1 (Glut-1) and tumor proliferative activity assessed by Ki-67 expression provide prognostic information in patients with non-small-cell lung cancer (NSCLC). Here, we compared the prognostic significances of FDG uptake, and of Glut-1 and Ki-67 expressions in patients with NSCLC.

Methods

NSCLC patients (n=53, F:M=16:37, age 61.9±12.1 years) who underwent curative resection after FDG-PET were enrolled. Thirty-one patients had stage I, 15 stage II, and 7 stage III disease. Patients were treated by surgery only (n=12), surgery plus adjuvant oral chemotherapy (n=32), or surgery plus adjuvant intravenous chemo- or radio-therapy (n=9). Maximum standardized FDG uptake values (maxSUV), and the Glut-1 and Ki-67 expressions of resected tumors were analyzed for correlations and relations with tumor recurrence. The median follow-up duration was 15 months.

Results

Thirteen (24.5%) of the 53 patients experienced recurrence during a median follow-up of 8 months and significant correlations were found between maxSUV, Glut-1, and Ki-67 expressions (r=0.48–0.79, p<0.001). Univariate analysis revealed that disease-free survival (DFS) was significantly correlated with maxSUV (<7 versus ≥7, p=0.001), % Ki-67 expression (<25% versus ≥25%, p=0.047), tumor size (<3cm versus ≥3cm, p=0.027), and tumor cell differentiation (well/moderate versus poor, p=0.011). However, multivariate Cox proportional analysis identified maxSUV as the only determinant of DFS (p=0.005). Patients with a maxSUV of ≥7 (n=14) had a significantly lower 1-year DFS rate (57.1%) than those with a maxSUV of <7 (n=39, 89.7%).

Conclusion

FDG uptake is more valuable than Glut-1 or Ki-67 expression in terms of predicting prognosis in patients with resected NSCLC.

Keywords: FDG uptake, Glucose transporter, Ki-67, Non-small-cell lung cancer, PET