Fused PET/MRI images in the therapeutic follow-up of recurrent chordoma: A case report

Abstract

Chordoma is an uncommon and malignant bone tumor that mainly occurs in the sacrum. Despite successful radical resection followed by radiotherapy, this tumor is still associated with a high rate of recurrence. As far as we know, this is the first reported case of recurrent chordoma where the integrated PET/MRI was used to ensure accuracy for staging and treatment management. We present a case of a 76-year-old man with a history of sacrococcygeal chordoma treated surgically 2 years earlier. Recently, a local recurrence has been suspected following the appearance of a subcutaneous nodule on the surgical scar. Therefore, a pelvic MRI scan was done showing hypointense and hyperintense nodules in weighted T1 and T2 images, respectively. The fused PET/MRI images revealed the presence of abnormal foci of 18F-FDG uptake not only in the multiple lesions identified in the MRI but also in the adjacent soft tissue, suggestive of extensive sites of recurrence. In conclusion, fused PET/MRI acquisitions hold the potential for a significant contribution to managing recurrent chordomas and refining therapeutic follow-up.