Primary colon natural killer (NK)/T-cell lymphoma, nasal type, with perforations: a case report and literature review.

Extranodal natural killer (NK)/T-cell lymphoma-nasal type (ENKTL-NT) is a rare, aggressive subtype of non-Hodgkin's lymphoma associated with Epstein-Barr virus (EBV) infection and has a poor prognosis. ENKTL-NT primarily involves the nasal cavity, and the colon as the primary site has rarely been reported. Its lack of a characteristic clinical presentation makes early diagnosis difficult to diagnose early, and misdiagnosis is common without the use of immunohistochemistry of specimens. To further understand this rare solid tumor, we report a case in a 51-year-old male patient admitted to hospital with abdominal pain as the primary symptom. A provisional diagnosis of gastrointestinal perforation was made on the basis of enhanced computed tomography of the abdomen, and emergency surgery was performed. However, 58 days after discharge, he suffered a second colonic perforation, underwent emergency surgery and was diagnosed with primary colonic ENKTL-NT based on the immunohistochemical results of the surgical specimen. He was transferred to the oncology department for chemotherapy after recovery from surgery, with gemcitabine, oxaliplatin, and pegaspargase as the chemotherapy regimen. To date, he has completed 11 courses of chemotherapy, and is now in a significantly improved general condition with no signs of tumor recurrence. We also reviewed and compared the literature related to primary colonic ENKTL-NT.