Imaging assessment of malignancy screening using computed tomography and diffusion-weighted whole-body imaging with background body signal suppression in rheumatoid arthritis.

Objectives: To investigate differences in information obtained from plain computed tomography (CT) and diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) during malignancy screening in patients with rheumatoid arthritis.

Methods: We enrolled 524 patients with RA who underwent plain CT from the chest to the pelvis and DWIBS. CT and DWIBS were performed within 3 months of each other. Rheumatologists, radiologists, and pulmonologists interpreted the plain CT and DWIBS images.

Results: The prevalence of malignancy was 3.1%. Prostate, lung, breast, uterine, ovarian, and fallopian tube cancers were detected in 7, 4, 2, 1, 1, and 1 patient, respectively. The sensitivities of CT and DWIBS were 75.0% and 93.8%, respectively (P = .333). The specificities of CT and DWIBS were 76.0% and 85.8%, respectively (P < .001). The prevalence rates of interstitial lung disease, colonic diverticula, and kidney stones on CT were 17.6%, 27.1%, and 19.1%, respectively. The prevalence of lymphadenopathy in patients who underwent DWIBS was 3.6%.

Conclusion: This study suggests that DWIBS is superior to or equivalent to CT for malignancy screening. Our findings have important implications for imaging-based screening and can help address cancer-related issues in rheumatoid arthritis treatment.