Abdominal CT image shows an approximately 4.5 cm-sized low-density mass-like lesion at the Lt external iliac nodal region (A). On sequentially performed PET-CT, increased FDG uptake was identified on the same lesion (B). Two months after diagnosis of NK/T cell lymphoma, follow-up PET-CT revealed extensive multiple hypermetabolic mass on areas including both lungs, spleen, and nasal cavity (C, D).