[Clinicopathological features of de novo CD5-positive diffuse large B-cell lymphoma].

To investigate the relationship between the protein expression of C-MYC, bcl-2 and bcl-6 and the clinicopathological characteristics in patients with de novo CD5-positive diffuse large B cell lymphoma (CD5(+)DLBCL). Fifty seven cases of de novo CD5(+)DLBCL were collected at Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from February 2013 to September 2018. The hematoxylin-eosin stained slides were reviewed, and immunohistochemical (IHC) staining and FISH were used to analyze the relationship between C-MYC, bcl-2, bcl-6 expression and the clinicopathologic characteristics of patients. Among these 57 cases, 27 were male and 30 were female. The age of onset was 35-99 years old. The IHC expression rates of C-MYC, bcl-2 and bcl-6 were 50.9% (29/57), 84.2% (48/57), and 75.4% (43/57) respectively; and co-expression rate of C-MYC and bcl-2 proteins was 40.4 (23/57). There was no significant correlation between protein expression and patients' genders, clinical stage, the level of serum LDH,β2 microglobulin, IPI,B symptoms, bone marrow involvement and central nervous system recurrence (0.05). Univariate analysis showed that the median OS of C-MYC negative patients was significantly longer than C-MYC positive patients (0.05); and the median OS of patients without double expression was significantly longer than that of patients with positive expression (0.05), and bcl-6 positive patients had longer median OS than bcl-6 negative patients (0.05). There was no significant correlation between prognosis and bcl-2 protein expression (0.05) . Cox multivariate analysis showed C-MYC protein expression was an independent predictor of OS in de novo CD5(+)DLBCL (0.05). Bcl-2 protein expression has no effect on the prognosis in de novo CD5(+)DLBCL whereas bcl-6 expression is correlated with good prognosis. C-MYC protein expression could be used as an independent and effective index to predict the prognosis of patients with de novo CD5(+)DLBCL.However, the relationship between protein expression and gene rearrangement of C-MYC, bcl-2 and bcl-6 needs to be further explored.