Diffusion-weighted MRI for staging and evaluation of response in diffuse large B-cell lymphoma: a pilot study.
The aim of this study was to compare diffusion-weighted MRI (DW-MRI) with positron emission tomography/computed tomography (PET/CT) for the staging and evaluation of the treatment response in patients with diffuse large B-cell lymphoma (DLBCL). Institutional review board approval was obtained for this study; all subjects gave informed consent. Twelve patients were imaged before treatment and eight of these were also imaged after two cycles of chemotherapy using both DW-MRI and PET/CT. Up to six target lesions were selected at baseline for response assessment based on International Working Group criteria (nodes > 1.5 cm in diameter; extranodal lesions > 1 cm in diameter). For pretreatment staging, visual analysis of the numbers of nodal and extranodal lesions based on PET/CT was performed. For interim response assessment after cycle 2 of chemotherapy, residual tumor sites were assessed visually and the percentage changes in target lesion size, maximum standardized uptake value (SUVmax ) and apparent diffusion coefficient (ADC) from pretreatment values were calculated. In 12 patients studied pretreatment, there were 46 nodal and 16 extranodal sites of lymphomatous involvement. Agreement between DW-MRI and PET/CT for overall lesion detection was 97% (60/62 tumor sites; 44/46 nodal and 16/16 extranodal lesions) and, for Ann Arbor stage, it was 100%. In the eight patients who had interim assessment, five of their 49 tumor sites remained abnormal on visual analysis of both DW-MRI and PET/CT, and there was one false positive on DW-MRI. Of their 24 target lesions, the mean pretreatment ADC value, tumor size and SUVmax were 772 µm(2) /s, 21.3 cm(2) and 16.9 g/mL, respectively. At interim assessment of the same 24 target lesions, ADC values increased by 85%, tumor size decreased by 74% and SUVmax decreased by 83% (all p < 0.01 versus baseline). DW-MRI provides results comparable with those of PET/CT for staging and early response assessment in patients with DLBCL.
Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA; Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA.
Marilyn J
MJ
Siegel
Clint E
CE
Jokerst
Dhana
D
Rajderkar
Charles F
CF
Hildebolt
Sagun
S
Goyal
Farrokh
F
Dehdashti
Nina
N
Wagner Johnston
Barry A
BA
Siegel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010865:Pilot Projects; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed
apparent diffusion coefficient; diffuse large B-cell lymphoma; diffusion-weighted MRI; positron emission tomography/computed tomography (PET/CT); response to chemotherapy; standardized uptake value