Reverse of the differential uptake intensity of Tc-99m MIBI and Tc-99m V-DMSA by multiple myeloma lesions in response to therapy.
OBJECTIVE
The objective of this study was to compare the uptake changes of Tc-99m 2-methoxy isobutyl isonitrile (MIBI) and Tc-99m pentavalent dimercaptosuccinic acid (V-DMSA) in multiple myeloma (MM) lesions in response to high-dose chemotherapy (HDC).


METHODS
The authors compared Tc-99m MIBI and Tc-99m V-DMSA scans before and after HDC in a patient with focal MM lesions without amyloidosis who had received previous standard chemotherapy as well.


RESULTS
HDC had the effect of eliminating all Tc-99m MIBI uptake in the lesions. Tc-99m V-DMSA uptake was increased in lesions presenting significant initial Tc-99m MIBI uptake. In 1 particular lesion that demonstrated this phenomenon, magnetic resonance showed necrosis of the area of MM.


CONCLUSIONS
The authors consider that the effect of increasing Tc-99m V-DMSA uptake in the absence of an increase in viable plasma cells possibly reflects the treatment-generated inflammatory and fibrotic changes and not necessarily viable tumor tissue. Exclusive focal Tc-99m V-DMSA uptake in this clinical setting could be considered as a sign of effectively treated lesions and not a sign of deterioration.
Athanasoulis
T
T
Department of Nuclear Medicine "Alexandra" University Hospital, Athens, Greece. theathan@hol.gr
Koutsikos
J
J
Moulopoulos
L A
LA
Tsiouris
S
S
Dimopoulos
M A
MA
Zerva
C
C
D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000378:metabolism; D003907:Dexamethasone / Q000008:administration & dosage; D004317:Doxorubicin / Q000008:administration & dosage; D006801:Humans; D008297:Male; D009101:Multiple Myeloma / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000378:metabolism; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012680:Sensitivity and Specificity; D012886:Skull / Q000000981:diagnostic imaging / Q000187:drug effects; D004113:Succimer / Q000493:pharmacokinetics; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics; D013977:Tibia / Q000000981:diagnostic imaging / Q000187:drug effects; D016896:Treatment Outcome; D014750:Vincristine / Q000008:administration & dosage
D019275:Radiopharmaceuticals; D014750:Vincristine; D003907:Dexamethasone; D004317:Doxorubicin; D017256:Technetium Tc 99m Sestamibi; D004113:Succimer