Recently, a prospective multicenter international trial (NCT00921414) of mantle cell lymphoma found that SUVmax > 10.3 was associated with aggressive variants (Ki67 > 30%), and both significant shorter progression free and overall survival.[17] Meanwhile, the metabolic response reflected by PET/CT following therapies was also reported to be practical in predicting survival of patients with lymphomas.[18–20] So far; however, mostly due to the rarity of it, the prognostic value of 18F-FDG PET/CT in patients with PHL has rarely been described. This evidence concerns the gene MKI67 and lymphoma.