FDG-Avid Metastatic Non-Clear Cell Renal Cell Carcinoma Presenting as Intussusception.

A 47-year-old man with a history of metastatic non-clear cell left renal cell carcinoma, unclassified subtype, status post left radical nephrectomy 4 years prior, and treated with immunotherapy for approximately 2½ years, presented for 18 F-FDG PET/CT exam 7 months after immunotherapy was stopped. A contrast-enhanced CT exam performed 3 weeks prior demonstrated a new small bowel intussusception in the left upper quadrant. The PET/CT demonstrated focal FDG uptake in the segment of small bowel involved in the intussusception.