Tremblay MA, et al. – An analysis was performed to identify clinical and imaging features in patients with pathologically confirmed demyelinating lesions. Pathologically affirmed tumefactive demyelinating lesions (TDLs) call for careful clinical correlation, clinical follow–up, and imaging surveillance. Tumefactive demyelinating lesions carried nearly a 45% risk of near–term clinical relapse in this study, even when presenting initially as a solitary mass lesion, although sometimes clinically monophasic.