A case report of extranodal diffuse large B-cell lymphoma involving upper limb soft tissue in a patient with rheumatoid arthritis on immunosuppressive therapy

An 80-year-old woman affected by rheumatoid arthritis on immunosuppressive therapy was evaluated for an 11-month history of swelling of her left upper limb. The patient did not report systemic symptoms. Ultrasonographic examination showed hypoechoic masses in the upper limb soft tissue, brachial vein thrombosis, and suspected malignant axillary lymphadenopathy. The patient underwent an excisional biopsy of the lymphadenopathy for histologic examination; a diagnosis of diffuse large B-cell lymphoma was made. The patient started anticoagulation therapy and chemotherapy, with a follow-up at a hematology clinic. At a 3-month follow-up visit in our clinic, the swelling of her left upper limb decreased, and an ultrasonographic control demonstrated a reduction in the size and number of the soft tissue masses and resolution of vein thrombosis.