18-F-FLUORODEOXYGLUCOSE POSITRON-EMISSION-TOMOGRAPHY AS A NEW APPROACH TO DETECT LYMPHOMATOUS BONE-MARROW

Purpose: Bone marrow involvement in patients with malignant lymphoma i s considered a sign of generalised disease with less favorable prognos is. Bone marrow biopsy (BMB), which represents the standard diagnostic procedure, however, is associated with a high rate of false-negative findings, which may lead to errors in management. The present study wa s undertaken to investigate the efficacy of positron emission tomograp hy (PET) with 18-F-fluorodeoxyglucose (FDG-PET) as a new method to eva luate bone marrow involvement in patients with malignant lymphoma. Met hods: Seventy-eight consecutive, untreated patients with either non-Ho dgkin's lymphoma (NHL; n = 39) or Hodgkin's disease (HD; n = 39) were prospectively evaluated. Static FDG-PET imaging was performed followin g application of 270 MBq (F-18)-FDG. Attenuation correction was perfor med in 63 of 78 patients. Visual evaluation was performed by two exami ners unaware of the clinical data. Material for BMB (70 bilateral, 8 u nilateral) was obtained from the posterior iliac crest. Discordant res ults of PET and biopsy were settled, when possible, on the basis of fu rther biopsy or magnetic resonance imaging (MRI). Results: In addition to seven concordant positive and 57 concordant negative findings, bio psy revealed another four cases with bone marrow involvement not detec table by FDG-PET analysis (+5.1%). On the contrary, PET showed bone ma rrow areas of intensive FDG uptake that suggested bone marrow lymphoma in 10 patients with negative biopsies (+12.8%). In eight patients, FD G-PET findings were confirmed by either histologic verification (n = 4 ), MRI (n = 2), polymerase chain reaction (PCR) for rearranged immunog lobulin H sequences (n = 1), or clinical presentation (n = 1). Two cas es remained unresolved. Conclusion: The results indicate that FDG-PET has a high potential to detect bone marrow involvement in malignant ly mphoma. Besides confirming lesions found at BMB, FDG-PET provided addi tional information, which, in eight of 78 patients (10.3%),led to an u pgrade of the tumor stage. (C) 1998 by American Society of Clinical On cology.