Contributions
Abstract: PB1788
Type: Publication Only
Background
Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin’s lymphoma and it accounts for about half of all lymphomas in Taiwan. The gene expression profiles (GEP) may confer some clues for clinicians to predict the prognosis. According to the GEP, DLBCL can be divided into 3 subtypes: germinal center type, activated B-cell type and type III. The germinal center B-cell (GCB) phenotype of DLBCL usually results in a good prognosis with a 5-year overall survival (OS) of 59%, while the 5-year OS of activated B-cell (ABC) phenotype is poor (about 31%). Recent studies showed DLBCL with concurrent translocation of Myc and BCL2/BCL6 (double hits), the so-called double-hit lymphoma (DHL) may have a dismal prognosis in spite of the GCB phenotype.The previous studies showed concurrent BCL2 and Myc translocations account for about 75% of DHL while BCL6 translocated DHL is less 25%. However,we did not have any data about the frequency and clinical features of DHL in Taiwan.
Aims
We would like to understand the frequency of double hits in patients with DLBCL in Taiwan and figure out their clinical features.
Methods
We retrieved 88 patients with newly-diagnosed DLBCL in the Shuang-Ho Hospital from 2009 to 2016. The translocations of Myc, BCL2 and BCL6 were detected by the fluorescence in-situ hybridization (FISH), using the break-apart probes of target genes. We tested all samples with the Myc probe first and both BCL2 and BCL6 translocations would be screened for samples with positive Myc translocation.
Results
Among 88 DLBCL patients, we found 15 patients with Myc translocation, accounting for 17% of all DLBCL patients. Meanwhile, there were 9 patients with concurrent Myc and BCL2/BCL6 translocations, account for 10.2% (Figure 1A). Among them, two-thirds (6 patients) were BCL6-translocated while the others (3 patients) had BCL2 translocation(Figure 1B). This finding was quite different from the results of prior reports in which BCL2 translocation accounted for the majority of the double-hit lymphoma.
The median age of patients with DHL was 62 years(Table 1). In addition, the DHL group had a high ratio of advanced disease (88.9%), indicating a more extensive involvement at presentation. Meanwhile, the male gender was predominant in the DHL group (77.8%). Phenotype could not be identified in 1 BCL2-translocated patient because of lack of the residual sample. The others in this group were exclusively GCB phenotype. In contrast, two-thirds of BCL6-translocated DHL patients had non-GCB DLBCL. This result caused our attention because the majority of DHL patients were GCB phenotype in the prior reports.
In our cohort, the median OS of DHL patients was 344 days, compatible with results of previous studies, while that of the non-DH DLBCL patients were 574 days (Figure 2). It seemed that the DHL patients survived worse than its non-DH counterpart. In spite of this, there was no significant difference between these 2 groups in OS and the major factor was probably the small sample size of the DHL group.
Conclusion
The frequency of DHL in our institute was 10.2% and the majority of DHL were BCL6-translocated with an advanced disease(88.9%).
The DHL patients seemed to have a worse prognosis than non-translocated ones without a clinical significance.
Session topic: 21. Aggressive Non-Hodgkin lymphoma - Clinical
Keyword(s): BCL2, BCL6, Diffuse large B cell lymphoma, MYC
Abstract: PB1788
Type: Publication Only
Background
Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin’s lymphoma and it accounts for about half of all lymphomas in Taiwan. The gene expression profiles (GEP) may confer some clues for clinicians to predict the prognosis. According to the GEP, DLBCL can be divided into 3 subtypes: germinal center type, activated B-cell type and type III. The germinal center B-cell (GCB) phenotype of DLBCL usually results in a good prognosis with a 5-year overall survival (OS) of 59%, while the 5-year OS of activated B-cell (ABC) phenotype is poor (about 31%). Recent studies showed DLBCL with concurrent translocation of Myc and BCL2/BCL6 (double hits), the so-called double-hit lymphoma (DHL) may have a dismal prognosis in spite of the GCB phenotype.The previous studies showed concurrent BCL2 and Myc translocations account for about 75% of DHL while BCL6 translocated DHL is less 25%. However,we did not have any data about the frequency and clinical features of DHL in Taiwan.
Aims
We would like to understand the frequency of double hits in patients with DLBCL in Taiwan and figure out their clinical features.
Methods
We retrieved 88 patients with newly-diagnosed DLBCL in the Shuang-Ho Hospital from 2009 to 2016. The translocations of Myc, BCL2 and BCL6 were detected by the fluorescence in-situ hybridization (FISH), using the break-apart probes of target genes. We tested all samples with the Myc probe first and both BCL2 and BCL6 translocations would be screened for samples with positive Myc translocation.
Results
Among 88 DLBCL patients, we found 15 patients with Myc translocation, accounting for 17% of all DLBCL patients. Meanwhile, there were 9 patients with concurrent Myc and BCL2/BCL6 translocations, account for 10.2% (Figure 1A). Among them, two-thirds (6 patients) were BCL6-translocated while the others (3 patients) had BCL2 translocation(Figure 1B). This finding was quite different from the results of prior reports in which BCL2 translocation accounted for the majority of the double-hit lymphoma.
The median age of patients with DHL was 62 years(Table 1). In addition, the DHL group had a high ratio of advanced disease (88.9%), indicating a more extensive involvement at presentation. Meanwhile, the male gender was predominant in the DHL group (77.8%). Phenotype could not be identified in 1 BCL2-translocated patient because of lack of the residual sample. The others in this group were exclusively GCB phenotype. In contrast, two-thirds of BCL6-translocated DHL patients had non-GCB DLBCL. This result caused our attention because the majority of DHL patients were GCB phenotype in the prior reports.
In our cohort, the median OS of DHL patients was 344 days, compatible with results of previous studies, while that of the non-DH DLBCL patients were 574 days (Figure 2). It seemed that the DHL patients survived worse than its non-DH counterpart. In spite of this, there was no significant difference between these 2 groups in OS and the major factor was probably the small sample size of the DHL group.
Conclusion
The frequency of DHL in our institute was 10.2% and the majority of DHL were BCL6-translocated with an advanced disease(88.9%).
The DHL patients seemed to have a worse prognosis than non-translocated ones without a clinical significance.
Session topic: 21. Aggressive Non-Hodgkin lymphoma - Clinical
Keyword(s): BCL2, BCL6, Diffuse large B cell lymphoma, MYC