Cutaneous abscesses can result from many conditions and are primarily managed with incision, drainage and antibiotics, without the need for extensive diagnostic workup. We herein report a case of a B-cell lymphoma manifesting as an abscess on the back of a 67-year-old female. Standard therapies failed to improve her condition, and, by the time of tissue diagnosis, a greater than palm-sized necrotic ulcer eroding through skin and fat, and into the psoas muscle had developed. Primary or secondary cutaneous B-cell lymphomas almost never lead to tissue necrosis but should be entertained in cases of abscesses or ulcers with unusual presentation.