As chemokine receptor 4 (CXCR4), a key factor for tumor growth and metastasis, is overexpressed in the malignant B-cells of patients with WM/LPL at a high level [8–10], we previously conducted a prospective cohort study and reported that 68Ga-pentixafor, a CXCR4-targeted PET probe, was obviously more sensitive than 18F-FDG in detecting tumor involvement of WM/LPL (100% vs. 58.8%) [11–13]. Here, CXCR4 is linked to neoplasm.