[Bone disease in multiple myeloma. A study of 237 cases]

From 1984 to 1990 the authors reviewed the radiologic-clinical charts of 237 patients affected with multiple myeloma (MM). The series included 127 males and 110 females (mean age: 66 years) who had been classified according to Durie and Salmon clinical criteria. All the patients underwent X-rays of the skeleton, as recommended in international literature; moreover, 148 subjects underwent whole-body bone scintigraphy, and 130 bone marrow scintigraphy. A selected group of cases (18 male/female patients) were submitted to bone densitometry employing both quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA). The results follow: 1) in the first stage of the disease, a high number of patients (29.5%) exhibits no skeletal abnormalities on X-rays; the most common lesion locations include the spine (49%), skull (35%), pelvis (34%), ribs (33%), humeri (22%), femora (13%) and mandible (10%); 2) the most frequent pattern is osteolysis, as a characteristic "punched-out" multiple lesion; the second most frequent lesion is osteopenia (43%), especially in the spine; pathologic fractures are common (54%) in the ribs, vertebral bodies, limbs; typical associations of features and sites are seen on X-ray images, which sometime make diagnosis easier; 3) whole-body scintigraphy, revealing aspecific uptake only in the presence of pathological fractures, is not recommended in the first staging of the disease, but is considered as a valuable technique in the follow-up, when the patients become symptomatic; 4) bone marrow scintigraphy, especially in the "marrow expansion" pattern, might be considered as an attempt made by the body to recover the central space which was destroyed by myelomatous involvement. The prognostic value of this technique is still to be assessed; 5) bone densitometry, by confirming the grade of osteopenia, reveals that osteoporosis is a peculiar pattern of bone disease in MM, which is not related to age only; 6) conventional radiography of the skeleton is the method of choice in the diagnosis of lytic areas of MM, and remains, as yet, irreplaceable. The other diagnostic techniques--i.e., CT and MRI--can be used to evaluate the extent of bone and soft tissue involvement, in the cases with questionable diagnosis, and to assess the degree of marrow involvement.