Bilateral Orbital Soft-Tissue Metastases from Renal Neuroendocrine Tumor: Successful Theranostic Application of ⁶⁸Ga/¹⁷⁷Lu-DOTATATE with Improvement of Vision

(A) ⁶⁸Ga-DOTATATE PET/CT showing increased tracer uptake in widespread metastatic skeletal lesions; in cervical, mediastinal, abdominopelvic lymph nodes; and bilaterally in orbital soft-tissue lesions. (B) MRI of head showing oval to rounded T2-hyperintense and T1-hypointense lesions with moderate homogeneous enhancement involving left lateral rectus, left inferior oblique, right lateral rectus, and right inferior oblique muscles in intraconal locations with compression of left optic nerve, along with abnormal tracer uptake on fused PET/MRI. (C) Scan at 24 h after PRRT demonstrating adequate tracer uptake in multiple metastatic lesions.