Gastric involvement of extranodal NK/T-cell lymphoma, nasal type: a report of 3 cases with literature review.

Gastric involvement of extranodal natural killer/T-cell lymphoma, nasal type is extremely rare, and its clinicopathologic features are also poorly understood. Until now, only 4 cases have been reported in literature. In this article, 3 cases of extranodal natural killer/T-cell lymphoma, nasal type are reported. In this current series, one patient (case 2) was admitted to emergency due to life-threatened hemorrhage of the upper-digestive tract and the volume of blood loss was about 2000 mL. For case 3, the sample was a small piece of gastroendoscopy biopsy tissue. It is a challenge for pathologist to make the diagnosis for this special type of tumor. In all, 2 of 3 cases had a relevant history of midfacial extranodal natural killer/T-cell lymphoma, nasal type before. The other patient died of tumor 2 months later with no history of the tumor when she was alive. Literature review was carried out; The cases reported in this article are documented and compared with the 4 previously reported cases of tumor.