Zwarthoed C, et al. – Clinicians examined the clinicopathologic associations and prognostic meaning of different patterns of bone marrow (BM) 18F–FDG uptake in Hodgkin lymphoma (HL). The results validated that 18F–FDG PET scanning is a reliable tool for bone marrow involvement (BMI) assessment in HL, and BM biopsy is no longer needed for routine staging. Furthermore, the interobserver agreement for BMI in this study proved excellent and only focal 18F–FDG BM uptake should be considered as a harbinger of HL.