[Clinicopathological and molecular characteristics of NTRK-rearranged spindle cell neoplasms in the gastrointestinal tract].

Objective: To investigate the clinicopathological, immunophenotypic and molecular genetic characteristics, and differential diagnosis of NTRK-rearranged spindle cell neoplasms (NTRK-RSCNs) in the gastrointestinal tract. Methods: Two NTRK-RSCNs diagnosed at the Department of Pathology of the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China and one case diagnosed at Zhengzhou Central Hospital, Zhengzhou, China from 2019 to 2022 were collected. The clinical data, histopathology, immunophenotypes and prognosis were analyzed. Fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS) were used to detect NTRK gene rearrangements, while relevant literature was also reviewed and discussed. Results: Two patients were male and one was female, with the age of 17, 47 and 62 years, respectively. The tumors were located in the duodenum, ascending colon and descending colon, respectively. The tumors were protuberant masses with gray and rubbery sections. Their maximum diameter was 2.5, 5.0 and 10.0 cm, respectively. Histologically, the tumors invaded mucosa, intrinsic muscle and serosal adipose tissue. Tumor cells consisted of spindle or oval shaped cells with monotonous morphology and arranged in bundles or stripes pattern. Spindle cells were mildly to moderately atypical, with slightly eosinophilic cytoplasm and inconspicuous nucleoli. Necrosis and mitotic figures were observed in one high-grade tumor. All tumors expressed CD34, S-100 and pan-TRK in varying degrees. FISH analysis showed that NTRK1 gene was break-apart in 1 case and NTRK2 gene break-apart in 2 cases. NGS technologies showed LMNA::NTRK1 fusion in one case, STRN::NTRK2 fusion in another case. All patients recovered well after the surgery without recurrence at the end of the follow-up. Conclusions: NTRK-RSCN is rarely diagnosed in the gastrointestinal tract and has significant variations in morphology. It overlaps with various other mesenchymal tumors which should be considered as differential diagnoses. Be familiar with the features of histological morphology in combination with immunophenotype and molecular genetic characteristics can not only help diagnose NTRK-RSCNs, but provide therapeutic targets for clinical treatment.

[Clinicopathological characteristics of natural killer cell enteropathy: report of two cases and review of literature].

Objective: To study the clinicopathological and genetic features of natural killer (NK)-cell enteropathy for better understanding of this rare disease and prevention of its misdiagnosis. Methods: Two cases of NK-cell enteropathy were diagnosed in the First Affiliated Hospital of Zhengzhou University, China from October 2017 to February 2021. The clinical characteristics, morphology, immunohistochemistry, Epstein-Barr virus-encoded RNA (EBER) in situ hybridization and T cell receptor gene rearrangement were analyzed. The patients were followed up by a telephone interview. Results: The patients were both male, aged 40 and 28 years, respectively. Both patients were admitted to the hospital for an annual checkup without obvious gastrointestinal symptoms. The endoscopy showed that the gastric body of case 1 had a mucosal bulge, small area of congestion and erosion, while the rectum of case 2 had congestion and erosion. Microscopically, the lesions of the 2 cases were relatively limited. Many lymphoid cells infiltrated within the lamina propria of the mucosa and into the muscularis mucosa in case 2. In case 1, the glands were reduced in the lesion, and the glandular cavity was slightly compressed and deformed. There was no infiltration or destruction of the glands in either case. Lymphoid cells were atypical, with medium-to-large cell sizes. Their cytoplasm was medium-to-slightly abundant and appeared eosinophilic or translucent. In case 2, characteristic eosinophilic granules were seen in the cytoplasm of a few cells. The nuclei in both cases were round, oval and irregular, with fine chromatin, inconspicuous nucleoli, and no mitotic figures were noted. Necrosis was seen in case 1 while both cases had no central growth or destruction of blood vessels. Immunophenotyping showed that CD56, granzyme B and TIA-1 were positive in both cases, part of the cells was CD3-positive, and some cells were weakly CD4-positive in case 2. The CD5, CD8, CD30, ALK and B-lineage markers (CD20, CD79α) were all negative. The Ki-67 proliferation index was about 60% and 30%, respectively. Both cases were EBER negative. TCR gene rearrangement was polyclonal. Follow-up showed that none of the 2 patients had any special treatments and stayed well. Conclusions: NK-cell enteropathy is rare, with biological behaviors similar to benign tumors, and occasional recurrence. Its histology and immunophenotype are easily confused with NK/T cell-derived lymphomas. Combination of its unique endoscopic features, EBER negativity, polyclonal TCR gene rearrangement and good prognosis can confirm the diagnosis and avoid misdiagnosis and overtreatment.

[Clinicopathological and molecular genetic features of Burkitt-like lymphoma with 11q aberration].

Objective: To investigate the clinicopathological features, molecular genetics, treatment and prognosis of Burkitt-like lymphoma with 11q aberration (BLL-11q). Methods: Six cases of BLL-11q diagnosed at the First Affiliated Hospital of Zhengzhou University, from January 2016 to January 2020 were reviewed and analyzed using hematoxylin-eosin staining, immunohistochemistry, EBER in situ hybridization and fluorescence in situ hybridization. Clinical information including follow-up data was collected and analyzed. Results: The median age of the six immunocompetent patients was 29 years (range 20-38 years) and the male to female ratio was 5∶1. All patients had nodal disease in the head and neck region. Five patients had Ann Arbor stage Ⅰ-Ⅱ disease, while one patient had stage Ⅳ disease. Lymph nodes showed partial or total architectural effacement by a diffuse proliferation of monomorphic lymphocytes. Four cases were morphologically similar to Burkitt lymphoma, and two cases were unclassified with histological features between Burkitt lymphoma and diffuse large B-cell lymphoma. Mitotic figures, apoptosis and necrosis were conspicuous. Five cases exhibited the"starry sky"pattern. CD20, CD10 and bcl-6 were diffusely and strongly positive. The Ki-67 index was more than 95%. The follicular-dendritic-cell meshwork was noted in one case using CD21 stain. C-MYC was expressed variably. CD3, bcl-2, MUM-1, CD30 and TDT were negative in all cases. EBER in situ hybridization was also all negative. FISH analyses using C-MYC, bcl-2 and bcl-6 break-apart probes were all negative. All cases had the 11q23.3 gain/11q24.3 loss pattern, and 11q23.3 amplification was found in one case. IgH and IRF4 break-apart probes analysis was also negative. All patients were alive with no disease after a follow-up of 4 to 19 months. Conclusion: BLL-11q is a rare lymphoma that resembles Burkitt lymphoma morphologically and phenotypically, but lacks C-MYC gene rearrangements. Instead, it has a chromosome-11q alteration characterized by proximal gains and telomeric losses. It's necessary to improve our understanding of BLL-11q to avoid misdiagnosis and missed diagnosis.

Histocompatibility antigens associated with Behçet's disease in northern Han Chinese.

Among Han nationality Chinese and living in the northern area of the Yellow River, 120 patients suffering from Behçet's disease and 100 unrelated healthy individuals were typed for histocompatibility antigens (HLA)-A, -B, -C, and -DR and -DQ antigens. HLA-DR and DQ typing was performed on B-lymphocyte separated with Lympho-B-Kwik. The HLA-antisera were provided by 11th IHWC. Bf alleles and C4 allotypes were determined by immunofixation agarose-gel electrophoresis. HLA-B51 was found in 67/120 (55.83%) patients and in 12/100 (12%) controls, the Chi-square and relative risk values were 45.54 and 9.27, respectively (p < 0.0005). C4AQ0 frequency was significantly increased in the patient group. In the complete form group HLA-B51 was observed more frequently (62.79%). No significant differences of other HLA antigens, frequencies, Bf or B4 alleles were found between the groups.

Ependymin as a substrate for outgrowth of axons from cultured explants of goldfish retina.

Ependymin, a prominent protein of the brain's extracellular fluid (ECF) was previously implicated in the consolidation of memory and in the activity-driven sharpening of the retinotectal projection. Because both these phenomena probably involve the growth and elaboration of appropriate synapses, we have tested whether ependymin can serve as a substrate for the growth of axons from goldfish retinal ganglion cells in a culture assay. Ependymin (Ep), laminin (LAM), polylysine (PL), and Concanavalin A (Con A) were plated on glass coverslips either uniformly or in striped patterns. Ep alone, either soluble or partly polymerized (by dropping calcium concentration and pH), was a good substrate for axonal outgrowth, as good or better than PL and Con A, but not as good as LAM. Neurites grew faster on LAM (71 microns/h) than on Ep (32 microns/h) or on PL (22 microns/h). Fasciculation was low on LAM, intermediate on Ep, and highest on PL. In exclusive side-by-side stripe assays, axons preferred LAM over Ep, but gave weak or no preference for Ep over Con A or PL. With stripes of LAM + Ep alongside pure LAM, the axons preferred the mixture of LAM + Ep. When antibodies to Ep were plated in stripes over continuous Ep substrate, the axons avoided the antibody-blocked stripes and grew on the Ep stripes. Antibodies to Ep did not, however, block growth on laminin substrates, nor did antibodies to LAM block growth on Ep. Dot blots and western blots showed very little cross recognition between the antibodies. Ependymin is a good substrate for neurite outgrowth, which is normally present in ECF, and adhesion to Ep is independent of LAM and possibly additive to it.