Primary small intestinal natural killer/T cell lymphoma mimicking tuberculous peritonitis: report of a case and review of the literature.

Extranodal natural killer/T cell lymphoma is very rarely encountered in clinical practice. It has a high mortality rate and very short median survival. Early diagnosis of these rare tumors, especially those originating from the small intestine, is usually difficult because of its nonspecific symptoms. Herein, we describe a case of a primary small intestinal natural killer/T cell lymphoma in a 52-year-old man who presented with abdominal fullness and weight loss. The clinical symptoms, elevation of serum levels of cancer antigen-125, and presence of ascites initially led to the suspicion of tuberculous peritonitis. Abdominal computed tomography scan demonstrated a hypodense tumor in the jejunum. Finally, the tumor was surgically confirmed to be a natural killer/T-cell lymphoma. Although aggressive chemotherapy was prescribed, the patient subsequently died of disease progression. In addition, we also review the English literature on this rare disease.