Purpose: PET using 18F-FDG integrated with CT is beneficial for staging patients with non-Hodgkin lymphoma (NHL). The Ki-67 index is used to assess the proliferation potential of tumor cells. The aim of this study was to evaluate the correlation of the Ki-67 index in tissue samples with the SUV at different sites on dual-phase FDG PET/CT of patients with newly diagnosed NHL.
Materials and Methods: From September 2009 to March 2011, patients with newly diagnosed NHL who had received dual-phase FDG PET/CT for staging and biopsy samples that were evaluated for the Ki-67 expression were enrolled. The SUVmax of the biopsy site, the tumorous lesion sites, and 3 different bone marrow sites (right iliac crest, sternum, and L1) were measured. The SUVmean of the liver and spleen were also measured.
Results: There were a total of 27 patients in this study. Significant correlations were observed between the Ki-67 index and the SUVmax of the right iliac crest in patients with early-stage disease (stage I and II) patients, the SUVmax of the biopsy and whole-body lesion sites in patients with late-stage disease (stage III and IV), and the retention index of SUVmax of the right iliac crest in patients whose bone marrow were involved by lymphoma cells.
Conclusions: For patients with newly diagnosed NHL, the significant correlation between the Ki-67 index and the SUV in this study suggests that dual-phase FDG PET/CT may be used as a noninvasive measurement of tumor proliferation.