| Abstract: |
Background: We previously correlated non-Hodgkin's lymphoma (NHL) histology with 18 fluoro-2-deoxyglucose-positron emission tomography (FDG-PET) intensity: A standardized uptake value (SUV) >10 predicted aggressive lymphoma with >80% certainty and an SUV >13, with >90% certainty. Patients and methods: To evaluate SUV in transformed lymphoma, we identified all FDG-PET scans for NHL at Memorial Sloan-Kettering Cancer 1999-2007 with (i) biopsy-proven transformation, (ii) no therapy 60 days before PET scan and (iii) FDG-PET scans no more than 60 days before or 90 days after transformation. Results: In 5 of 40 patients, the biopsy site was excised before PET; in two, only marrow was biopsied. In the remaining 33 patients, the SUV of the biopsy site ranged from 3 to 38, mean 14, median 12. Eighteen of 33 biopsies (55%) had an SUV >10 and 16 (48%) >13. The highest SUV in a transformed lymphoma PET scan (SUV<sub>study-max</sub>) ranged from 3.2 to 40, mean 15, median 12. Twenty-five of 40 patients (63%) presented with an SUV<sub>study-max</sub> >10 and 20 (50%) >13. Conclusions: Like de novo aggressive lymphomas, the majority of transformations have a high SUV<sub>study-max</sub> for a given pretreatment staging study, although many do not have very high values. Transformation should be suspected in indolent lymphoma with high SUVs on FDG-PET. Biopsies should be directed to the site of greatest FDG avidity. © The Author 2009. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. |
