Non-osseous incidental findings in low-dose whole-body CT in patients with multiple myeloma

Abstract

Objective: The purpose of this study was to identify the frequency and grading of non-osseous incidental findings (NOIF) in non-contrast whole-body low-dose CT (LDCT) in patients with multiple myeloma. Methods: In the time period from 2010 to 2013, 93 patients with multiple myeloma were staged by non-contrast wholebody LDCT at our radiological department. LDCT images were analysed retrospectively for NOIF, which also included unsuspected extramedullary manifestation of multiple myeloma. All NOIF were classified as major or clinically significant, moderate or possibly clinically significant and minor or not clinically significant. Medical records were analysed regarding further investigation and follow-up of the identified NOIF. Results: In the 93 patients, 295 NOIF were identified (on average, 3.2 NOIF per patient). Most of the NOIF (52.4%) were not clinically significant, 25.8% of the NOIF were possibly clinically significant and 21.8% of the NOIF were clinically significant. Clinically significant NOIF were investigated further by CT after intravenous administration of contrast medium and/or by ultrasound or MRI. In 34 of these cases, extramedullary relapse of myeloma, occult carcinoma or infectious/septic incidental findings were diagnosed (11.5% of all NOIF). In the remaining 10.3% of the NOIF classified as clinically significant, various benign lesions were diagnosed. Conclusion: LDCT detected various non-osseous lesions in patients with multiple myeloma. 36.6% of the patients had clinically significant NOIF. Therefore, LDCT examinations in patients with multiple myeloma should be evaluated carefully for the presence of NOIF. Advances in knowledge: LDCT identified several NOIF. A total of 36.6% of patients with multiple myeloma had clinically significant NOIF. Radiologists should analyse LDCT examinations in patients with multiple myeloma not only for bone lesions, but also for lesions in other organs.CT is used for screening or staging in several malignancies.

Incidental findings in the skeletal musculature on computed tomography

“…3 Furthermore, the number of incidental findings varied from 2.8 to 3.2 per patient investigated. 3,9 Most frequently, different malignant lesions and cardiovascular findings incidentally detected on CT have been reported. 2,5,6,[8][9][10] Although skeletal muscles represent approximately 50% of total body mass, IFs on imaging investigations have been not reported previously.…”

“…7 Most studies that analyzed incidental findings on imaging, especially on CT, focused on the prevalence of several incidentally detected malignancies or clinically relevant findings. [2][3][4][5][6][8][9][10] To the best of our knowledge, there were no previous reports regarding incidental findings in the skeletal musculature. However, it is the largest region of the body and may contain different findings.…”

Guidelines for the use of imaging in the management of patients with myeloma

“…Whole body low‐dose CT is capable of demonstrating extramedullary disease (Surov et al , ) and correlates with whole‐body MRI findings (Wolf et al , ). As well as extramedullary myeloma, WBLDCT demonstrates clinically significant non‐osseous incidental findings (NOIF), such as occult carcinoma and infection, so careful extra skeletal review is mandated.…”

“…As well as extramedullary myeloma, WBLDCT demonstrates clinically significant non‐osseous incidental findings (NOIF), such as occult carcinoma and infection, so careful extra skeletal review is mandated. Surov et al () retrospectively reported an average of 3·2 NOIF per patient which were clinically significant in 36·6% of 93 patients with myeloma undergoing WBLDCT.…”

Imaging of Multiple Myeloma

“…In addition to the high sensitivity, CT has additional advantages such as improved assessment of fracture risk, the ability to visualize extraosseous myeloma, and biopsy, surgery, and radiation planning. Moreover, clinically relevant, non-bone-related secondary diagnoses can be made on CT in approximately one-third of cases (▶ Table 2) [17].…”