Abstract 4900
Background
Diffuse large B-cell lymphoma (DLBCL) is heterogenous morphologically, clinically and genetically. Although half of patients could be cured by frontline R-CHOP, approximately 10%-15% are refractory or relapse within the 1st year. Here, we investigated the molecular landscapes of patients with diverse responses to R-CHOP.
Methods
Targeted sequencing was performed on baseline samples of 105 DLBCL patients. After a median follow-up of 67 months, 63 (60.0%) patients had refractory or relapsed disease. All patients received R-CHOP(-like) regimen as the first-line treatment. After excluding double-hit and primary central system lymphoma, 81 patients with measurable disease before initial treatment and followed over 1 year were included for survival analysis. Patients who received less than a partial remission in the first-line setting or those relapsed within the first 12 months since the initiation of the treatment were defined as having primary refractory.
Results
Collectively, we identified 1162 mutations spanning 103 genes from this cohort. The most commonly seen mutations included PIM1(33%), MYD88 (29%), BCL2 (29%), TP53 (29%), CD79B (25%) and KMT2D (24%). Patients with TP53 mutations were more likely to have primary refractory disease (41.7% vs 7.4%, p = 0.002). For those with TP53 disruptive mutations, primary refractory is also more common (22.9% vs. 0%, p = 0.006). Interestingly, BCL-2 somatic hypermutation (SHM) was only seen in patients without primary refractory disease (p = 0.014). The International prognostic index (IPI) score and other clinical characteristics were comparable between the 2 groups. Furthermore, TP53 mutations were correlated with shorter PFS (p = 0.001) and OS (p = 0.049). Next, we investigated mutation landscape in patients with WT TP53 (n = 58) and found that patients harboring MYD88 L265P had significantly inferior PFS than those with WT or non-265P (p = 0.046).
Conclusions
We revealed that patients with TP53 mutation are more likely to have primary refractory to standard R-CHOP. This study also showed the prognostic potential of MYD88 L265P in those with WT TP53 and indicated that distinct subgroups could be identified by TP53 and MYD88 L265P mutations.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4614 - Predictors of Response to Checkpoint Inhibitors in Naïve and Ipilimumab-Refractory Melanoma
Presenter: Domenico Mallardo
Session: Poster Display session 3
Resources:
Abstract
2901 - IFN-γ/IL-10 ratio as predictive biomarker for response to anti-PD-1 therapy in metastatic melanoma patients
Presenter: Emilio Giunta
Session: Poster Display session 3
Resources:
Abstract
2306 - Multiplex Chromogenic Immunohistochemistry (IHC) for Spatial Analysis of Checkpoint-Positive Tumor Infiltrating Lymphocytes (TILs)
Presenter: Scott Ely
Session: Poster Display session 3
Resources:
Abstract
1678 - The role of PD-L1 expression as a predictive biomarker in advanced renal cell carcinoma: a meta-analysis of randomized clinical trials.
Presenter: Alberto Carretero-Gonzalez
Session: Poster Display session 3
Resources:
Abstract
5138 - Radiomic Features as a Non-invasive Biomarker to Predict Response to Immunotherapy in Recurrent or Metastatic Urothelial Carcinoma
Presenter: Kye Jin Park
Session: Poster Display session 3
Resources:
Abstract
5800 - Integrative combination of high-plex digital profiling techniques and cluster analysis to reveal complex immune biology in the tumor microenvironment of mesothelioma
Presenter: Carmen Ballesteros-Merino
Session: Poster Display session 3
Resources:
Abstract
5736 - Predictive factors of response to immunotherapy in 198 patients with metastatic non-microcytic lung cancer (mNSCLC): real world data from 2 university hospitals in Spain
Presenter: Juan Felipe Cordoba Ortega
Session: Poster Display session 3
Resources:
Abstract
5645 - Evaluating Lung CT Density Changes Among Patients with Extensive Stage Small Cell Lung Cancer (ES-SCLC) Treated with Thoracic Radiotherapy (TRT) alone or TRT Followed by Combined Ipilimumab (IPI) and Nivolumab (NIVO).
Presenter: Kujtim Latifi
Session: Poster Display session 3
Resources:
Abstract
1540 - Immuno-oncology therapy biomarkers differences between polyoma-virus positive and negative Merkel cell carcinomas
Presenter: Zoran Gatalica
Session: Poster Display session 3
Resources:
Abstract
4538 - Can we improve patient selection for phase 1 clinical trials (Ph1) based on Immuno-Oncology score prognostic index (VIO)?
Presenter: Ignacio Matos Garcia
Session: Poster Display session 3
Resources:
Abstract