Prognostic value of bone marrow 18 F-FDG uptake on PET/CT in lymphoma patients with negative bone marrow involvement.

Objective: The study evaluated the significance of 18F fluorodeoxyglucose ( ¹⁸ F-FDG) uptake of bone marrow (BM) for predicting progression-free survival (PFS) in lymphoma patients without BM involvement.
Subjects and Methods: Ninety-five patients with histopathologically proven lymphoma, 7 Hodgkin's lymphoma and 88 non-Hodgkin's lymphoma, who underwent ¹⁸ F-FDG positron emission tomography/computed tomography (PET/CT) and BM biopsy for staging work-up and 40 normal subjects were retrospectively enrolled. Maximal ¹⁸ F-FDG uptake of lymphoma (Lmax), mean ¹⁸ F-FDG uptake of BM (BM SUV) and BM-to-liver uptake ratio (BLR) were measured. Prognostic value of BM SUV and BLR for predicting PFS were assessed.
Results: Of the 95 patients, 35 (36.8%) were histopathologically or clinically diagnosed with BM involvement of lymphoma. There were significant differences of BLR among lymphoma patients with/without BM involvement and normal subjects (P<0.05). For all patients, high risk indicated by International Prognostic Index (IPI) score and Lmax were significantly associated with PFS on multivariate analysis (P<0.05). For 60 patients without BM involvement, BM SUV and BLR were independent prognostic factors for PFS along with performance status and Lmax (p<0.05). Among patients without BM involvement, high ¹⁸ F-FDG uptake of BM was associated with significantly worse PFS than low ¹⁸ F-FDG uptake of BM, with no significant difference in PFS apparent compared to patients with BM involvement.
Conclusion: In lymphoma patients without BM involvement, ¹⁸ F-FDG uptake of BM was significantly associated with worse PFS. Patients with high ¹⁸ F-FDG uptake of BM showed similar prognosis to those with BM involvement.