Detection of Lymphomatous Marrow Infiltration using F-18 FDG PET at Initial Staging and after chemotherapy

Yun, Mijin; Kim, Young Jin; Moon, Jin Wook; Park, Sang Joon; Lee, Jong Doo

Abstract

PURPOSE
To assess the ability of FDG PET for the detection of bone marrow infiltration compared to iliac crest biopsy in patients with lymphoma. MATERIALS AND METHODS: Seventy-three patients (30 females and 43 males, mean age of 47 years old) with malignant lymphoma (4 Hodgkin's disease, HD and 69 Non-Hodgkin's lymphoma, NHL) were included. FDG PET was performed for staging in 53 patients and to assess treatment response after the completion of chemotherapy in 20 patients. Final conclusions were based on biopsy, other imaging studies, or clinical follow-up. RESULTS: There were 54 (74%) of the 73 patients in whom FDG PET and iliac crest biopsy were concordant. Forty-seven of the 54 patients showed concordant negative results while the remaining 7 patients had concordant positive results. Of 19 patients with discordant results, FDG PET accurately detected bone marrow infiltration in 6 patients with negative iliac crest biopsy. On the contrary, iliac crest biopsy identified bone marrow infiltration in 12 of the 19 patients. In remaining one of the 19 patients with discordant results, iliac crest biopsy was true negative but FDG PET was falsely positive. CONCLUSION: FDG PET seems to be an adjunct in detecting marrow infiltration that may not be revealed by iliac crest biopsy at staging. For the assessment of treatment response, it may be less helpful than biopsy in detecting microscopic residual disease in the bone marrow.