Primary skeletal muscle lymphoma with unusual soft tissue metastases in the stomach and pancreas detected by 18F-FDG PET/CT.

A 69 y/o woman with a history of primary diffuse large B cell lymphoma in the right thigh muscle was referred for recurrence evaluation with 18F-FDG PET/CT. After routine courses of chemoradiation, MRI was done in order to evaluate treatment response with inconclusive findings. 18FDG PET/CT revealed abnormal uptake in the primary site of the disease as well as secondary involvement of stomach, pancreas, pelvic lymph nodes, and both tibiae. Our case showed the importance of 18F-FDG PET/CT in the detection of unusual soft tissue extension of lymphoma.