The present study found that ALK-positive ALCL had a higher 18F-FDG uptake than that of ALK-negative ALCL (SUVmax: 22.1 ± 14.3 vs. 15.1 ± 6.6, t = 2.354, P = 0.023), which was consistent with the results reported by Lee DY [9]. The gene discussed is ALK; the disease is anaplastic large cell lymphoma.