Study On C-MYC Protein Expression And Its Significance In Diffuse Large B Cell Liyphoma

Objective:To detect the expression of c-Myc protein in diffuse large B cell lymphoma tissues, to study the expression of c-Myc and relationship with clinical pathological features of diffuse large B cell lymphoma and its effect on prognosis.Methods:A retrospective analysis from 2007 February to 2014 August in The Affiliated Tumor Hospital of Guangxi Medical University from patients with diffuse large B cell lymphoma 107 cases, All cases were confirmed as diffuse large B cell lymphoma by pathological biopsy. Collected into groups of patients with clinical and pathological features, pathological wax block data and follow-up status. Use of immunohistochemical detection of c-Myc protein expression, and to analyze the relationship between c-Myc protein and clinical pathological characteristics and prognosis.Result:1. Detection of diffuse large B cell lymphoma tissues the expression rate of c-Myc was 17.76%2. There is no significant difference on c-Myc protein positive expression group and negative expression group patients in sex, age, LDH, ECOG score, Ann-Arbor staging, extranodal involvement organ number, B symptoms,, immune subtype, chemotherapy and short-term efficacy (p>0.05)3. According to univariate analysis that age, number of extranodal organ involvement, ECOG score, B symptoms, chemotherapy,the number of cycles of chemotherapyWith nothing to do in patients with DLBCL (P>0.05); Female, LDH increased, IPI score of 3-5, non-GCB subtype, c-Myc protein positive expression of patients has a poor OS (P<0.05); Ann-Arbor stage Ⅲ-Ⅳ, LDH increased, IPI score 3-5, non-GCB subtype, c-Myc protein positive expression of patients has a poor PFS (P<0.05).4. Multivariate analysis showed that the positive expression of c-Myc protein were independent prognostic factors of OS (P=0.037), for the PFS is not an independent prognostic factor (P=0.112); Ann-Arbor stage Ⅲ-Ⅳ are independent prognostic factors of PFS (P=0.007), for the OS is not an independent prognostic factors (P=0.151).5. c-Myc protein positve expression in the IPI score of 0-2 group (The low risk group) than c-Myc protein negative expression in the IPI score of 0-2 group has poorer OS (P=0.001) and PFS (P=0.041); c-Myc protein positve expression and c-Myc protein negative expression in the IPI score of 3-5 group (The high-risk group) about the OS and PFS had no significant difference (P= 0.120 and 0.412).Conclusion:1. the application of immunohistochemical detection of c-Myc protein is simple and reliable, and economic method, Our study use ROC curve in consideration of the optimal combination which the sensitivity and specificity to select the maximum Youden index point to determine the expression of c-Myc protein in the threshold is 40%, the sensitivity was 50%, specificity was 96.9%, the area under the ROC curve was 0.74.2. The positive expression of c-Myc protein in patients with OS shortened, c-Myc were independent prognostic factors for OS.3. Ann-Arbor stage Ⅲ-Ⅳ in patients with PFS shortened, Ann-Arbor stage were independent prognostic factors of PFS.4. The expression of c-Myc protein can further distinguish of patients with poor prognosis in IPI low risk group, and provide a theoretical basis for making clinical decision.