The results of a recent retrospective analysis show that whole-body CT scans are superior to x-rays in the detection of bone lesions in multiple myeloma patients.

Dr. Kelechi Princewill from the University of Maryland in Baltimore presented these findings at the American Roentgen Ray Society annual meeting  in Vancouver, Canada, earlier this month.

“Low-dose, whole-body CT was significantly better than [x-rays] in detecting lesions in the spine, ribs, sternum, and flat bones,” said Dr. Princewill.

Bone destruction is a common clinical feature of multiple myeloma. Lesions form when bone destroying cells, called osteoclasts, become overactive (see Beacon related news). The number of bone lesions detected in a myeloma patient is a factor in assessing the stage of disease.

In the United States, the standard method for detecting bone lesions is through a radiographic (x-ray) skeletal survey. However in Europe, studies have demonstrated that whole-body computerized tomography (CT) scans are better than x-rays for detecting bone lesions.

CT scans construct a three-dimensional image of bones and soft tissue from a series of x-rays. However, CT scans are not typically used in the U.S. due to higher levels of radiation exposure.

“Using modified protocols and exposure parameters, we were able to significantly reduce the radiation doses to our patients without significantly compromising the image quality required to detect myeloma lesions. The average CT dose used in our study was approximately nine times lower than doses used in the acquisition of standard body CT studies,” explained Dr. Princewill.

The goal of this study was to compare the accuracy of lesion detection through x-rays versus low-dose, whole-body CT scanning.

Dr. Princewill and his colleagues retrospectively reviewed data from 300 myeloma patients between 2004 and 2011. The patients included in the study were evaluated with both x-rays and a CT scan less than three months apart.

Only images obtained from low-dose CT scans were used for comparison with the x-rays. Two radiologists independently recorded the number of bone lesions found in the images produced from both procedures.

A total of 51 patients with a median age of 56 years were included in the final analysis. The average time between the imaging procedures was 26 days. The number of lesions recorded from the whole-body CT scans was 968, compared to 248 lesions found in the x-rays.

Eighteen percent of patients had no lesions present on either image.

According to the researchers, the additional number of lesions detected by the whole-body CT scan would have led to an upstaging of disease in 61 percent of patients. Specifically, 13 stage 1 patients (disease requiring no treatment) would have been upstaged to stage 2 (disease requiring treatment), nine stage 1 patients to stage 3 (advanced disease), and nine stage 2 patients to stage 3.

For more information, please see abstract 130 in the American Journal of Roentgenology.