Endoscopic and clinicopathological characteristics of colorectal T/NK cell lymphoma

Abstract

Background Colorectal T/natural killer (NK)-cell lymphomas (TNKCL) are very rare. Endoscopic and clinicopathological characteristics of colorectal TNKCL have not been clearly demonstrated. In this study, we demonstrated the clinical characteristics of colorectal TNKCL. Methods Endoscopic and clinicopathological characteristics were investigated in 27 patients with colorectal monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), adult T-cell leukemia/lymphoma (ATLL), and other types of TNKCL. Results Nine TNKCL patients (33%) were classified as MEITL, 11 (41%) as ATLL, and seven (26%) as other. Four patients with Epstein-Barr Virus-positive (EBV+) TNKCL, two indolent T-cell lymphoproliferative disorder and one anaplastic large cell lymphoma were included in the other group. Endoscopically, six MEITL (67%) and five ATLL (46%) showed diffuse-infiltrating type, in which the main endoscopic lesion was edematous mucosa in MEITL, while aphthoid erosion and edematous mucosa were typical in ATLL. Ulcerative type was identified in four other group patients (57%), including two EBV+ TNKCL. An increase in atypical T-intraepithelial lymphocytes (T-IELs) was noted in seven MEITL (88%) and six ATLL (60%) patients, but not in the other group (0%) patients. Five MEITL patients (56%) showed features of lymphocytic proctocolitis with increased CD8+ T-IELs. Conclusions MEITL and ATLL occasionally invaded the colorectum, and primary involving MEITL was observed. Diffuse infiltrating type was the characteristic endoscopic finding in colorectal MEITL and ATLL, while ulcerative type was observed in the other group. Features of lymphocytic proctocolitis may be prodromal findings of MEITL.

A case of intestinal T‐cell lymphoma, not otherwise specified, that showed characteristic findings by magnified endoscopy combined with narrow‐band imaging

“…To the best of our knowledge, no previous studies on the endoscopic features of ITCL, NOS have been reported. Diffuse infiltrating type was reported as the characteristic endoscopic finding of T‐cell lymphomas such as MEITL and adult T‐cell leukemia/lymphoma 6 . The present case showed elevated legion and edematous mucosa with focal depressions and was classified as diffuse infiltrating type.…”

“…Diffuse infiltrating type was reported as the characteristic endoscopic finding of T-cell lymphomas such as MEITL and adult T-cell leukemia/lymphoma. 6 The present case showed elevated legion and edematous mucosa with focal depressions and was classified as diffuse infiltrating type. Microscopic features of ITCL, NOS are also not established because of the heterogeneity in morphology and immunophenotype.…”

Cellular Origins and Pathogenesis of Gastrointestinal NK- and T-Cell Lymphoproliferative Disorders

“…Endoscopic findings include oedematous and finely granular mucosa, erythematous erosions and shallow ulcers [236][237][238][239][240]. Macroscopically, the tumour presents as a transmural, ulcerative mass, often with perforation.…”

“…The lymphomatous infiltrate comprises relatively monotonous, medium-sized lymphocytes with scarcity of reactive inflammatory cells and necrosis [191,220,222,225,226,228] (Figure 4). The intestinal mucosa adjacent to the invasive tumour features increased IELs, which may be atypical in morphology and phenotype, whilst IELs appear normal further away from the tumour [220,225], the latter mimicking celiac disease or lymphocytic colitis [228,236,238,239]. .…”