[Bone disease in multiple myeloma. Analysis of 253 controlled cases, with reappraisal of diagnostic criteria and current imaging techniques].

Abstract

Two hundred and fifty-three multiple myeloma patients (136 males and 117 females; mean age 66 years) classified by the clinical criteria of Durie and Salmon underwent skeletal radiography; 148 of them had total body bone scintigraphy, and 130 bone marrow scintigraphy. A selected group of them (18 patients, both males and females) had densitometric bone examination, employing both quantitative computed tomography (QCT) and dual energy X-ray absorptiometry (DXA). The results can be summarized as follows: 29.7% of patients exhibited no skeletal abnormalities at early staging. Spine (49%), skull (35%), pelvis (34%), ribs (33%), humeri (22%), femora (13%), and mandible (10%) were the most frequently involved locations. The main pattern is osteolysis as a characteristic "punched-out" multiple lesion (43.3%), but the most frequent lesion is osteopenia (43.9%), particularly evident in the spine; pathologic fractures (54%) are seen in the ribs, vertebral bodies, limbs; typical radiographic associations of features and sites are observed, which sometimes make diagnosis easier. Total body scintigraphy, revealing aspecific uptake only in the presence of pathologic fractures, is not recommended in the first staging of the disease, but it is considered as an important technique in the follow-up, when the patients become symptomatic. Bone marrow scintigraphy, especially in the "marrow expansion" pattern, might be considered as a form of compensating attempt to recover the lost central space, destroyed by myelomatous involvement, of which it defines the pathologic and prognostic status. Bone densitometry, as it confirms the grade of osteopenia, reveals that osteoporosis is a peculiar characteristic pattern of bone disease in multiple myeloma, not only due to age. Conventional skeletal radiography is the main support in the diagnosis of lytic areas of multiple myeloma, and it remains--today--irreplaceable. The other diagnostic techniques (i.e., CT and MRI) may be used to detect the extent of bone and soft tissue involvement, in areas of complicated anatomy, and to define the degree of marrow involvement.