Soft Tissue Lymphoma Mimicking a Lipomatous Tumor on Fine Needle Aspiration: A Diagnostic Pitfall

Abstract

Primary soft tissue lymphoma is very rare. Herein we describe a case of a previously healthy patient with a tumor presenting clinically as a soft tissue mass and suspected to be a soft tissue sarcoma on magnetic resonance imaging (MRI). This was initially diagnosed as an atypical lipomatous tumor on fine needle aspiration (FNA) biopsy; however, surgical excision confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL). The purpose of this report is to emphasize this potential diagnostic pitfall and describe briefly the cytologic features of soft tissue lymphoma.