18F-FDG PET/CT, 99mTc-MIBI, and MRI in evaluation of patients with multiple myeloma.
New imaging techniques have been introduced to assess the extent and severity of disease in multiple myeloma (MM) patients. The aim of our study was to compare newer imaging modalities-such as (18)F-FDG PET/CT, (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) scintigraphy, and MRI-to assess their relative contribution in the evaluation of MM patients at diagnosis.


METHODS
Thirty-three newly diagnosed patients with MM were prospectively studied. Diagnosis and staging were made according to standard criteria. All patients underwent whole-body (18)F-FDG PET/CT, whole-body (99m)Tc-MIBI, and MRI of the spine and pelvis within 10 d, and imaging findings were compared.


RESULTS
(18)F-FDG PET/CT was positive in 32 patients (16 focal uptake, 3 diffuse uptake, 13 focal and diffuse uptake), (99m)Tc-MIBI was positive in 30 patients (6 focal, 11 diffuse, 13 focal and diffuse uptake), and MRI of the spine and pelvis was positive in 27 patients (6 focal, 13 diffuse, 8 focal and diffuse uptake). (18)F-FDG PET/CT showed a total of 196 focal lesions (178 in bones and 18 in soft tissues), of which 121 were in districts other than the spine and pelvis, whereas (99m)Tc-MIBI visualized 63 focal lesions (60 in bones and 3 in soft tissues), of which 53 were in districts other than the spine and pelvis. In the spinal and pelvic regions, (18)F-FDG PET/CT detected 75 focal lesions (35 in spine and 40 in pelvis), (99m)Tc-MIBI visualized 10 focal lesions (1 in spine and 9 in pelvis), and MRI detected 51 focal lesions (40 in spine and 11 in pelvis).


CONCLUSIONS
In whole-body analysis, (18)F-FDG PET/CT performed better than (99m)Tc-MIBI in the detection of focal lesions, whereas (99m)Tc-MIBI was superior in the visualization of diffuse disease. In the spine and pelvis, MRI was comparable to (18)F-FDG PET/CT and (99m)Tc-MIBI in the detection of focal and diffuse disease, respectively. Because myelomatous lesions may often occur out of spinal and pelvic regions, MRI should be reserved to the evaluation of bone marrow involvement of these districts, whereas (18)F-FDG PET/CT can significantly contribute to an accurate whole-body evaluation of MM patients. Finally, whole-body (99m)Tc-MIBI, despite its limited capacity in detecting focal lesions, may be an alternative option when a PET facility is not available.
Fonti
Rosa
R
Istituto di Biostrutture e Bioimmagini-CNR, Napoli, Italy. fontir@tin.it
Salvatore
Barbara
B
Quarantelli
Mario
M
Sirignano
Cesare
C
Segreto
Sabrina
S
Petruzziello
Fara
F
Catalano
Lucio
L
Liuzzi
Raffaele
R
Rotoli
Bruno
B
Del Vecchio
Silvana
S
Pace
Leonardo
L
Salvatore
Marco
M
D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis*; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D017256:Technetium Tc 99m Sestamibi