Clinical impact of CD5 expression in Korean patients with diffuse large B-cell lymphoma

Development and Validation of a Novel Prognostic Nomogram for CD5-Positive Diffuse Large B-Cell Lymphoma: A Retrospective Multicenter Study in China

Background

CD5-positive diffuse large B-cell lymphoma (CD5+ DLBCL) is a rare subtype of DLBCL with invasive clinical features and poor prognosis. Current clinical variables based on prognostic systems for DLBCL are inadequate to accurately stratify the prognosis of CD5+ DLBCL.

Methods

A total of 195 CD5+ DLBCL patients were retrospectively recruited from nine centers in Huaihai Lymphoma Working Group. MaxStat analysis was used to identify optimal cutoff points for continuous variables; univariable and multivariable Cox analyses were used for variable selection; Kaplan–Meier curve was used to analyze the value of variables on prognosis; and C-index, Brier score, and decision curve analysis were measured for predicting model performance.

Results

The derivation and validation cohorts consisted of 131 and 64 patients. Of the whole cohort, median age at diagnosis was 61 years, of whom 100 (51.28%) were males and the 5‐year overall survival rate was 42.1%. MYC, BCL-2, and the coexpression of MYC/BCL-2 could distinguish the survival of CD5+ DLBCL. Multivariable analysis showed that age, IPI, red blood cell count, neutrophil count, MYC expression, and hepatosplenomegaly were independent predictors, and the prognostic nomogram was developed. The C‐index of the nomogram was 0.809 in the derivation and 0.770 in the validation cohort. Decision curve analysis proved that compared with IPI, the specific nomogram showed a better identification in CD5+ DLBCL.

Conclusion

The proposed nomogram provided a valuable tool for prognosis prediction in patients with CD5+ DLBCL.

CD5+ diffuse large B-cell lymphoma: a narrative review

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, and cell surface cluster of differentiation (CD) 5 expression may represent a distinct subset. Here, we provide a narrative review of CD5+ DLBCL to understand its clinical implications. Between 5-10% of DLBCL express CD5, making it an uncommon subset. Studies have variably shown that CD5+ DLBCL may be associated with increased age, high lactate dehydrogenase, B symptoms, extra-nodal sites, higher International Prognostic Index score, and advanced stage. CD5+ DLBCLs are more likely to express Bcl-2, MYC, and MUM1; a large proportion exhibit an activated B-cell (ABC)-like phenotype. The balance of studies generally supports an independent prognostic value of CD5 in DLBCL While more aggressive first-line regimens have been advocated for CD5+ DLBCL, including dose-adjusted R-EPOCH and autologous stem cell transplant, evidence to support these approaches is lacking; further study is warranted to identify the optimal treatment strategy for this disease entity.

Molecular characteristics of terminal deoxynucleotidyl transferase negative precursor B-cell phenotype Burkitt leukemia with IGH-MYC rearrangement

Precursor B cell phenotype Burkitt lymphoma/leukemia with IGH-MYC is a rare subtype of Burkitt lymphoma (BL). BL and B lymphoblastic leukemia/lymphoma (B-ALL/LBL) differ as regards treatment and the distinction between these two entities is crucial. Patients demonstrating a terminal deoxynucleotidyl transferase (TdT)-positive precursor B cell phenotype with IGH-MYC rearrangement have been reported to be molecularly distinct from BL and closer to B-ALL/LBL. We investigated the molecular characteristics of two cases of a rare but distinct TdT-negative precursor B cell phenotype BL. Both patients showed FAB L3 morphology with IGH-MYC translocation, but had precursor B cell immunophenotypes including dim to moderate expression of CD45 and absence of BCL6, CD20, monoclonal kappa, and lambda light chain expression. To characterize the molecular features, we performed exome sequencing and analyzed the breakpoint junction of the IGH-MYC rearrangement. We detected KMT2D mutations in both cases, a rarely acquired chromatin modifying gene mutation in BL. The breakpoint analysis revealed that the IGH-MYC rearrangement occurred due to an aberrant VDJ recombination in one case. The treatment protocols differed, including high-grade lymphoma treatment and standard B-ALL treatment. Complete remission was achieved in the patient who received B-ALL treatment. The degree of resemblance of BL and B-ALL differed between two cases, but the molecular pathogenesis and manifesting features of both TdT-negative precursor B cell phenotype BL case were distinct from classic BL, which indicates the need for a better understanding of this uncommon entity that does not fit in current diagnostic and classification categories.

CD5 and CD43 Expression are Associate with Poor Prognosis in DLBCL Patients

Objective

To investigate the expression and clinical significance of CD5 and CD43 in diffuse large B cell lymphoma (DLBCL) (unspecified).

Methods

Sixty - five patients with diagnosed DLBCL were enrolled. The expressions of CD5, CD43, CD10, Bcl-6 and Mun-1 were detected by immuno histochemistry. The relationship between CD5 and CD43 and clinicopathological features and prognosis of DLBCL was analyzed.

Results

In sixty - five adult DLBCL patients , 6 cases of DLBCL (9.2%) were CD5 positive, 24 cases of DLBCL (36.9%) were CD43 positive, 5 cases of DLBCL (7.7%) were both CD5 and CD43 positive. 40 cases of DLBCL (61.5%) were CD5 and CD43 negative. CD5 expression was not related to age, sex, clinical stage, type of immunophenotype (Hans typing), location, and whether infected with hepatitis B virus (HBV); CD43 expression was correlated with immunophenotyping and HBV i nfection, but was not correlated with the age, sex, clinical stage, and site. Median survival time was significantly lower in CD5- and CD43- positive DLBCL patients than CD5- and CD43-negative patien ts.

Conclusion

The prognosis of DLBCL patients may be worse with positive CD5 and CD43 expression.