Over 3 months, a healthy man developed prominent systemic symptoms that def
ied investigation. Physical examination was noncontributory, and extensive
studies revealed only a marked acute-phase response associated with increas
ed serum IL-6 levels. A whole body Gallium-67 scan was crucial in diagnosis
, directing attention to high uptake in the left paraspinal and psoas muscl
es. Open surgical excision biopsy was performed, guided by intraoperative u
se of a gamma-probe, Removed tissue was diagnosed as diffuse, large B-cell
non-Hodgkin lymphoma of muscle (stage I-E), a rare extranodal lymphoma. Cyc
lophosphamide, doxorubicin, vincristine, and prednisone (CHOP) therapy was
given, and the patient became asymptomatic with normal blood tests and was
thought to be in remission. However, a repeat Gallium-67 scan revealed recu
rrent multifocal disease and salvage chemotherapy was instituted. A 47,XXY
karyotype (Klinefelter syndrome) was later identified, possibly associated
with the lymphoma.