Search

Objective: To investigate the optimal experimental conditions (including antigen retrieval time, antibody titers and antibody incubation time) for reliable detection of programmed death-ligand 1 (PD-L1) expression using PD-L1 (22C3) antibody concentrate, and to establish a laboratory developed test for PD-L1 detection. Methods: Using Dako PD-L1 IHC 22C3 pharmDX staining procedure and scoring guidelines as the standard reference (group A), the PD-L1 expression in 25 tissue specimens (including 15 lung cancer tissues, 5 tonsil tissues and 5 placenta tissues) was detected with Flex+/HRP detection kit (EnVision) under 8 different experimental conditions (groups B1 to B8). The staining results were then compared to those in group A. Results: In group B1, 3 tissue samples showed the percentages of PD-L1 positive tumor cells were similar to those in group A, while the percentages of PD-L1 positive tumor cells were lower than those in group A in the other samples. In group B7, two case showed a positive rate higher than that in group A that was also above the positive cut-off value, and the rest of the samples had a percentage of PD-L1 positive tumor cells slightly higher than that in group A, but still below the positive cut-off value. The staining results of group B8 were the closest to those of group A compared with the other groups. Although the percentages of PD-L1 positive tumor cells in the B2 to B6 groups were decreased in various degrees as compared with group A, they were still concordant with group A's classification (positive vs. negative) and would not change the choice of clinical treatments. Conclusions: The experimental conditions are associated with detection rate of PD-L1 expression using 22C3 antibody. In the present study, the most-suitable alterative conditions in the PD-L1 detection using 22C3 antibody concentrate are those applied in the group B8 (including antigen retrieval in Dako PT Link tank at 97 ℃, pH 6.0 for 40 min and incubation with 22C3 antibodies (1∶100 dilution) at room temperature for 60 min, incubation with EnVision Flex+Linker at room temperature for 30 min, incubation with EnVision/HRP at room temperature for 30 min and DAB staining for 5 min), which could provide reliable results at minimum costs.

Objective: To study the expression of phosphates signal transducer and activator of transcription 3 (pSTAT3) and programmed death ligand-1 (PD-L1) in extranodal NK/T cell lymphomas (ENKTCL) and the relationships of pSTAT3 and PD-L1 expression with the clinicopathological characteristics and prognosis of ENKTCL. Methods: Fifty-one cases of ENKTCL diagnosed at Guangdong Provincial People's Hospital from June 2015 to February 2019 were included in the study. The expression of pSTAT3 and PD-L1 was examined using immunohistochemistry. Results: There were 35 males and 16 females, ranging from 18 to 85 years old with a median age of 47 years. The positive rates of pSTAT3 and PD-L1 expression were 68.6% (35/51) and 76.5% (39/51), respectively. pSTAT3 expression was correlated with PD-L1 expression ( P =0.033, R =0.322), while there were no associations of pSTAT3 and PD-L1 expression with the clinicopathological characteristics of ENKTCL, including age, sex, clinical site, B symptom, Ann Arbor stage, LDH value, EBV DNA load of peripheral blood and international proliferation index score. Kaplan-Meier survival analysis showed the prognoses of the pSTAT3 and PD-L1 positive groups were slightly better than the respective negative groups, but the differences were not significantly ( P >0.05). Conclusions: pSTAT3 is highly expressed in extranodal NK/T cell lymphoma and related to the expression of PD-L1, which provides a potential target and rationale for combinations of targeted therapies and immune checkpoint blockade inhibitors in the treatment of ENKTCL.

Objectives: To investigate the clinicopathological features, therapy and prognosis of primary cardiac CD5-positive diffuse large B-cell lymphoma with C-MYC and bcl-2 double expression. Methods: Two cases diagnosed at Guangdong Provincial People's Hospital were included, the clinical data were collected; the tumor morphology, immunophenotypic profiles, therapy and prognosis were analyzed. Results: Case 1 was a 55-year-old man and case 2 was a 61-year-old women. Intraoperatively, both cases showed large masses in the right atrium or ventricle, involving adjacent tissue. Pathologically, the tumors were composed of diffusely infiltrating large lymphoid cells with high mitotic activity and apoptosis. The tumor cells were positive for CD20, CD5, bcl-6, MUM1, C-MYC and bcl-2, and the Ki-67 index was equal or greater than 90%. Case 1 had bcl-6, but not bcl-2 or MYC gene rearrangements. No MYC, bcl-2 or bcl-6 gene rearrangements were detected in case 2. Case 1 defaulted chemotherapy after operation and died 1 month after diagnosis. Case 2 was treated with 4 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) therapy after surgery and attained partial remission, and was then treated with apatinib and ibrutinib, and remained stable 18 months after initial diagnosis. Conclusion: Primary cardiac CD5-positive diffuse large B-cell lymphoma with C-MYC and bcl-2 double expression usually shows large infiltrative mass in the right atrium or ventricle, non-germinal center like immunophenotype and high proliferation index, and this may contribute to the aggressiveness of primary cardiac lymphoma.

Objective: To investigate the clinicopathological features, treatment and prognosis of duodenal-type follicular lymphoma. Methods: Four cases of duodenal-type follicular lymphoma diagnosed at Guangdong General Hospital from 2014 to 2015 with detailed clinical data were included. The histomorphology, immunophenotype, treatment and prognoses were analyzed. Results: The patients' age ranged from 51 to 57 years (mean 54 years), and there were 2 males and 2 females. The involved sites were gastric fundus in one case, second portion of the duodenum in two cases and terminal ileum in one case. All patients presented with multiple mucosal granules or nodules at endoscopy. Microscopically, there were multiple mucosal neoplastic follicles, constituting grade 1-2 disease based on nodal follicular lymphoma grading system. The tumor cells were positive for CD20, CD10, bcl-6 and bcl-2. CD21 highlighted the follicular dendritic meshwork mainly at the periphery of the follicles. Proliferation index was low. Three patients received rituximab monotherapy for 4 cycles, leading to complete remission. One patient refused therapy and the disease progressed to systemic lymphoma 15 months after the initial diagnosis. Conclusions: Duodenal-type follicular lymphoma is a special variant of follicular lymphoma with indolent clinical course. The tumor exhibits morphology of low grade follicular lymphoma with characteristic dendritic meshwork at the periphery of the follicles and a low proliferation index. Prognosis is excellent. Rituximab monotherapy is treatment of choice, but a small minority of patients may progress to systemic disease.

Objective: To evaluate the expression of βF1 and T cell receptor (TCR)γ in T lymphoblastic lymphoma/leukemia(T-LBL/ALL), and investigate the clinicopathological features. Methods: Fifty-one cases of T-LBL/ALL were collected at Guangdong General Hospital from 2010 to 2016, the expression of βF1 and TCRγ was assessed by immunohistochemistry. Results: There were 13 cases of children and adolescents, and 38 cases of adults. The expression rates of βF1 and TCRγ were 27.5%(14/51) and 15.7%(8/51) respectively. The proportion of adults in αβ T-LBL/ALL, TCR-silent T-LBL/ALL and γδ T-LBL/ALL was 7/14, 79.3%(23/29)and 8/8 respectively, and the difference was significant ( P =0.023). There was no statistical difference in sex, LDH, bone marrow involvement and Ann arbor stage among these three groups( P >0.05). γδ T-LBL/ALLs included 6 cases of CD4(-)/CD8(-) phenotype, whereas αβ T-LBL/ALL included 7 cases of CD4(+) /CD8(+) phenotype. There was significant difference in CD4/CD8 expression among these three groups( P <0.01). Conclusions: γδ T-LBL/ALL occurred only in adults, with predominantly CD4(-)/CD8(-) phenotype. αβ T-LBL/ALL occurred more common in children and adolescents, with predominantly CD4(+) /CD8(+) phenotype.