Rectal Neuroendocrine Tumor With Inferior Vena Cava Tumor Thrombosis Diagnosed With 68Ga-DOTANOC PET/CT.

A 69-year-old man with a history of back pain, urinary obstruction, and deep vein thrombosis of both lower extremities 4 years earlier was diagnosed with rectal neuroendocrine tumor, grade 2, Ki-67 index 3%. Ga-DOTANOC PET/CT images showed a left pelvic mass extended to the lumen of the inferior vena cava with a high affinity for somatostatin receptor. A tubular focus of radiotracer accumulation after the course of inferior vena cava with filling defect was suggestive of tumor thrombus.