Primary abdominal muscle lymphoma.

Primary skeletal muscle lymphoma accounts for <1% of all lymphomas; a fraction of these arise within the abdominal muscles. Here, we describe the case of an 84-year-old woman who presented with multiple painful abdominal masses that proved to be diffuse large B-cell lymphoma and we discuss the main features of the disease. Clinical differential diagnosis from soft tissue sarcoma can be extremely difficult. Therefore, accurate pathological diagnosis including optimal tissue processing and immunohistochemical staining is vital to ensuring proper treatment.