Summary

Hodgkin lymphoma typically presents as a nodal lesion and infrequently involves extra nodal sites. Although cases of primary extra-nodal Hodgkin lymphoma have been reported previously, the reality of the primitive nature of the disease was difficult to authenticate with traditional high resolution imaging techniques, such as computed tomography or magnetic resonance imaging, because they cannot evaluate the spread of the disease throughout the whole body. We report here a case of primary osseous Hodgkin lymphoma, regarded as stage I extranodal IE thanks to the important contribution of a new imaging technique, the 2-[18F]-fluoro-2-deoxy-d-glucose positron emission tomography/ computed tomography (18F-FDG-PET/CT). PET enables systemic Hodgkin lymphoma with secondary bone invasion to be distinguished from primitive osseous Hodgkin lymphoma. This technique is highly specific in demonstrating the isolated osseous localisation of the tumour and should be recommended in all patients with putative osseous lymphoma.