[The role of PET scan in the investigation of the lymphatic spreading of Hodgkin's disease].

The authors investigated the role of PET, as a non-invasive diagnostic method, in the analysis of lymphatic spreading of Hodgkin's disease (HD). Whole-body FDG scans were carried out in 71 patients along with [11C]-methionine examinations, if necessitated by inconclusive FDG results. Based on these findings involvement-frequencies were calculated for each lymphatic region. The three most frequently involved lymphatic regions were the mediastinum (83.1%), the left cervical and left supraclavicular regions (78.9%) and the right cervical and right supraclavicular regions (76.1%). These data support the hypothesis that HD originates from the cervical or supraclavicular regions and reaches the distant sites by basically retrograde spreading in a non-random manner. The appropriate values of site involvement-rate were compared with those obtained by other authors based on pathologic staging and a good correlation was found. The high level of correspondence between these involvement-frequencies supported the general validity (i.e. valid for both treated and untreated cases) of the principles governing lymphatic spreading of HD.