18F-FDG PET/CT: a review of diagnostic and prognostic features in multiple myeloma and related disorders

Abstract

Conventional radiographic skeletal survey has been for many years the gold standard to detect the occurrence of osteolytic lesions in patients with multiple myeloma (MM). However, the introduction of more sensitive imaging procedures has resulted in an updated anatomic and functional Durie and Salmon "plus" staging system and has remarkably changed the diagnostic and prognostic approach to this tumor. It is now established that (18)fluorine-fluorodeoxyglucose ((18)F-FDG) positron-emission tomography (PET) combined with low-dose computed tomography (CT), shortly designated PET/CT, exhibits a higher screening and diagnostic sensitivity and specificity over the skeleton X-ray. In patients with monoclonal gammopathy of undetermined significance and in those with smoldering MM, PET/CT is consistently unable to detect focal and/or diffuse marrow abnormalities. Conversely, based on a systematic review of 18 studies comprising almost 800 MM patients, PET/CT was able to detect MM osteolytic lesions with a sensitivity of approximately 80-90% and a specificity of 80-100%. Importantly, a poor degree of concordance has also been emphasized between PET/CT and whole-body magnetic resonance imaging (WB-MRI) in that when both techniques were applied to the same patients, double-positive results were recorded in approximately 30% of the cases, but in the majority of them, a higher number of lesions were revealed with PET/CT than with MRI. Double-negative results, on the other hand, were found in about 22% of the patients. Because PET/CT is able to identify tumor foci throughout the body, it can be usefully applied to the study of solitary bone plasmacytoma and extra-medullary plasmacytoma: In both conditions, the detection of additional, previously overlooked sites of skeletal involvement would falsify the diagnosis of single-district disease, upstage the tumor, and therefore require a different therapeutic approach. In addition, although PET/CT is poorly sensitive to diffuse bone marrow infiltration, it can anticipate a site of impending fracture throughout the body and can discriminate old from new pathologic fractures. MRI should, however, be preferred when vertebral bodies are suspected to be involved and the risk of vertebral fracture is to be assessed. PET/CT is a sensitive and reliable procedure to evaluate the response to chemotherapy and/or radiotherapy, which is shown by a remarkable reduction and sometimes total disappearance of FDG accumulation in the involved bony structures, although these structures remain morphologically abnormal. Conversely, an increased focal uptake of FDG in apparent remission patients often precedes clinically overt relapse. PET/CT should be preferred to other imaging techniques to assess the remission status after autologous stem cell transplantation. In patients with primary and remission-induced non-secretory MM, the use of PET/CT may help to early detect single or multiple districts of focal non-secretory relapse. Osteonecrosis of the jaw, its location, and extent in MM patients receiving b...

Is there any complimentary role of F-18 NaF PET/CT in detecting of osseous involvement of multiple myeloma? A comparative study for F-18 FDG PET/CT and F-18 FDG NaF PET/CT

“…The basic concept in its application in MM is that malignant plasma cells, that infiltrate the bone marrow, consume much more glucose than normal cells [9][10][11][12]. Many studies [13][14][15] consistently emphasized that F-18 FDG imaging was an accurate and dependable technique in detecting MM osteolytic lesions in a higher number of patients and with greater sensitivity and specificity compared with routinely performed radiographs, bone scan, and CT or MRI. Based on a systematic review of 18 studies comprising almost 800 MM patients, PET/CT was able to detect MM osteolytic lesions with a sensitivity of approximately 80-90 % and a specificity of 80-100 % [15].…”

The role of 18F-FDG PET/CT before and after the treatment of multiple myeloma: Our clinical experience

“…The median PFS and also the median OS for FDG PET/ doi:10.18282/amor.v3.i1.167 radiographic skeletal survey has been for many years the gold standard in detecting osteolytic lesions in MM patients [14] . Until 2006, the staging of patients suffering from MM is done according to the Durie and Salmon criteria based on laboratory testing (determination of serum calcium, haemoglobin, and serum and urine M proteins) and conventional radiography [13,15] .…”

“…In addition, numerous studies have shown that FDG PET/ CT is more sensitive in the detection of osteolytic lesions in MM compared to whole-body X-ray [7,8,16] . Based on a systematic review from 2012 involving 18 studies and 798 patients, FDG PET/CT was able to detect MM osteolytic lesions with a sensitivity of approximately 80%-90% and a specificity of 80%-100% [14,17] . It is important to mention that, currently, qualitative or semiquantitative criteria used to define the positivity of a FDG PET or FDG PET/ CT scan for recurrence or disease progression of MM are not clearly specified.…”

“…It is important to note that FDG PET/CT is consistently unable to detect focal and/or diffuse marrow abnormalities in patients with MGUS and smoldering MM [14] . Therefore, the International Myeloma Working Group (IMWG) included the use of whole-body MRI (or MRI of the spine and pelvis, if the whole-body MRI is not available) in the workup for smoldering MM [29] .…”

“…In another review, based on the summarized data, the authors concluded that FDG PET/CT is a suitable method to evaluate the response to chemotherapy and/or radiotherapy and/or autologous stem cell transplantation (ASCT). The good response is shown by a remarkable reduction or a total disappearance of FDG accumulation in the involved bone structures, although these structures remain morphologically abnormal [14] . Moreover, several studies have confirmed that FDG PET/CT has shown the best results in the follow-up of patients with MM and has an independent prognostic value both at diagnosis and after treatment [3] .…”