Emre Ergul  ( General Surgery Department, Ankara Ataturk Teaching and Research Hospital, Ankara, Turkey )
Ibrahim Cagatay Sisman  ( General Surgery Department, Ankara Ataturk Teaching and Research Hospital, Ankara, Turkey )
Ahmet Kusdemir  ( General Surgery Department, Ankara Ataturk Teaching and Research Hospital, Ankara, Turkey )

Madam, Intestinal T-cell lymphoma (TCL) is an uncommon entity among primary gastrointestinal lymphomas. It is usually an aggressive disorder that may be associated with coeliac disease. The expression of the natural killer (NK) cell marker CD56 has been reported to occur in NK-cell lymphomas/leukemias and a small group of peripheral TCLs.^1,2 Primer NK-cell lymphoma of the colon is extremely rare.
We came cross a-57-year old male patient, who was admitted to the emergency department with a main complaint of fecaloid vomiting, abdominal distension and pain. He had no history of any disease, especially coeliac disease. On physical examination the patient's abdomen was distended, rigid and tenderness was present in all quadrants especially at left-lower quadrant. The laboratory examination showed haemoglobin 14.4 g/dL, white blood cell count 15.103 /µL, blood urea nitrogen 60 mg%, and serum creatinine 1.2 mg%. The white blood cell distribution was normal. The abdominal X-ray showed multiple air-fluid levels and the abdominal computerized tomography was reported as lumen obscuring wall thickness in a 6cm segment at rectosigmoidal junction. An emergency operation was performed by a preoperative diagnosis of ileus due to colon tumour.
Laparotomy revealed a lumen obstructing tumour at the rectosigmoidal junction. Sigmoid resection was performed, mesorectum was protected and sigmoid artery was ligated near the bifurcation. Immunohistopathological examination of the specimen reported as NK cell type (CD2+, CD3-, CD56+, TCRdelta-1-, betaF1-) lymphoma (Figure) with pericolic 7/10 of lymph node metastasis. There was no infiltration at other pelvic and paraaortic lymph nodes. The tumour cells also had negative dyeing with S-100, CD99, HMB45, CD117, CD138, lambda and kappa anticores, epithelial markers like; EMA, pancytokeratine, CK7 and CK20, neuroendocrine markers like; NSE, cromograine and sinaptophysine, mesenchymal marker vimentine and lymphoid markers as LCA, CD3 and CD20. A chemo/radiotherapy program was planned.
Incidence and localization of primary gastrointestinal (GI) lymphomas varies worldwide. In Middle Europe and North America GI lymphomas in adults arise predominantly in the stomach, whereas intestinal malignant lymphomas are rather infrequent and show no site prevalence in the bowel.  In contrast, malignant lymphomas particularly localized in the upper small intestine are frequent in various parts of the Middle East.  [(Fig1)]  CD56 is a 200 to 220kd glycoprotein expressed predominantly on human NK cells and a minor subset of T cells mediating major histocompatibility complex-nonrestricted cytotoxicity. Lymphomas expressing CD56 are rare aggressive malignancies sharing the propensity for extranodal disease such as gastrointestinal tract.³ NK-like T cells are surface CD3+, express NK-cell antigens, such as CD56, and rearrange their TCR, which distinguishes them from true NK cells.⁴ In our case the cells represented a true NK-cell immunocytomorphology.
T cell lymphomas of intestines are strictly associated with enteropathies especially with coeliac disease.⁵ Our patient had no history of any enteropathies. Also, there was no positive feature to suspect enteropathy. Review of the literature, showed less than ten cases of primer colonic T cell lymphomas. Nevertheless, primer NK-cell lymphoma of colon is extremely rare; we found only 3 cases in a study. No primer colonic NK-cell lymphoma presenting as ileus was reported.

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