A 67-year-old man with sigmoid colon cancer was referred for PET/CT for the evaluation of increased tumor marker after one year of diagnosis. FDG-PET/CT revealed tumoral wall thickening with intense FDG uptake at the sigmoid colon consistent with recurrence and metastatic mesenteric and paraaortocaval lymph nodes. In addition, there was widespread heterogeneously increased FDG uptake in the skeleton consistent with bone marrow involvement (Fig. 2). Bone marrow biopsy proved mucinous tumor involvement despite a platelet count of 179,000 per µL.