Recurrent Lymphoma Detected on F-18 FDG Coincidence Imaging with Negative Findings on Ga-67 Citrate Scintigraphy

Ga-67 citrate scintigraphy and computer tomography have been used in tumor staging, to determine disease extent, and for the pre- and post-therapeutic management of Hodgkin's and non-Hodgkin's lymphoma. Today, localization of hypermetabolic tissue using F-18 FDG is beginning to play a role in the staging and restaging of lymphoma. The authors report a case of recurrent Hodgkin's lymphoma in a 31-year-old man detected by F-18 FDG. Findings of the Ga-67 citrate scintigram were negative. Palpable right axillary adenopathy was found on routine physical examination follow-up. Comparison with previous negative findings obtained with Ga-67 citrate was unchanged. However, computed tomography revealed new right axilla lymphadenopathy, prompting further investigation with F-18 FDG SPECT, which showed hypermetabolic activity corresponding to the region of the right axilla involvement. Pathologic examination showed changes indicative of interfollicular recurrence of Hodgkin's lymphoma.