Neoplasia occurring in the sinus tract is a well known complication of chronic osteomyelitis. Squamous cell carcinoma, fibrosarcoma, myeloma, and malignant lymphoma have been reported. We report a rare case of malignant lymphoma arising from osteomyelitis. The patient was a 59-year-old male. At 15 years-of age, he had open fracture in the distal end of the right femur, and had suffered from chronic osteomyelitis since then. On March 2004, he had swelling, redness and pain around the right knee. He underwent antibiotic therapy, but it was not effective. Xp, CT, and MRI revealed osteolytic lesions in the distal end of the femur and swelling soft tumor in the vicinity. A part of the soft tumor was excised by open biopsy, and histological diagnosis was malignant lymphoma.
At internal medicine department in our hospital, chemotherapy (R-CHOP therapy: 6cycles) and radiation therapy (total: 40Gy) were done. After four months, MRI indicated that soft tumor had disappeared.
