[Case of recurrent delayed radiation myelopathy with 5-year remission interval]

We report a 47-year-old woman with relapsed delayed radiation myelopathy (DRM), occurring 5 years and 10 years after radiation therapy for nasopharyngeal carcinoma at 37 years old. Sensations of pain and temperature had been disturbed in the right leg since 42 years old. MRI showed Gadolinium-enhanced lesion as a ring-like-enhancement of the spinal cord at C1-2 on T1-weighted image (T1WI), with high signal area and swelling of the spinal cord at the upper C1 to C6 areas on T2-weighted image. We diagnosed her as having DRM after considering the differential diagnosis, e.g., multiple sclerosis, spinal tumor and other neurological diseases. Her sensory symptoms quickly improved following therapy with prednisolone and warfarin. Although she remained healthy for a few years, dysesthesia of the neck on the right side appeared 5 years later after the first clinical occurrence. At this time, MRI demonstrated Gadolinium-enhanced lesion as a ring-like enhancement of the spinal cord at C2 on T1WI. but the area also differed from that of previous lesion; a high signal area and swelling of the spinal cord was also seen on FLAIR image of the medulla and upper C1 to C6. For recurrence of DRM, we administered prednisolone and warfarin. Thereafter, the patient recovered and the spinal cord lesion on MRI decreased markedly. The clinical course demonstrated that administration of prednisolone and warfarin might be effective for relapsed DRM.