PhD Scientific Days 2022

Budapest, 6-7 July 2022

Pathology and Oncology III. (Poster discussion will take place in the Aula during the Coffee Break)

Investigation of TP53 Mutations in Chronic Lymphocytic Leukemia Using Next Generation Sequencing

Előadó neve

Dr. László, Tamás

Előadó munkahelye

HCEMM-SU Molecular Oncohematology Research Group, Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest

Előadó telefonszáma

+36706704706

Előadó e-mail címe

laszlo.tamas@stud.semmelweis.hu

Az előadás címe

Investigation of TP53 Mutations in Chronic Lymphocytic Leukemia Using Next Generation Sequencing

Szerző(k) neve és munkahelye

Tamás László1, Lili Kotmayer1, Viktória Fésüs1,2, Csaba Bödör1

1HCEMM-SU Molecular Oncohematology Research Group,Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest
2Kaposi Mór University Teaching Hospital of County Somogy, Kaposvár

Bemutatás módja

Poszter

Szekció

Pathology and Oncology III. (Poster discussion will take place in the Aula during the Coffee Break)

Language of the presentation

English

Preferred session

Pathology and Oncology

Összefoglaló szövege

Introduction: TP53 aberrations (TP53 mutations and/or deletions of the chromosomal region 17p) are associated with chemoresistance, hence represent a contraindication for use of standard chemoimmunotherapy in chronic lymphocytic leukemia (CLL). Subclonal (low-burden) TP53 mutations represent a subpopulation of the tumor cells, with variant allele frequencies (VAF) below the 10% threshold. Clinical impact of these sublclonal variants is still the subject of extensive study, with some results suggesting the same unfavourable prognostic impact as in the case of clonal alterations.
Aims: In our study, we aimed to explore the subclonal architecture and the clinical impact of low-burden TP53 mutations in a Hungarian ”real-world” cohort.
Method: Peripherial blood samples were collected from 509 CLL patients from 11 Hungarian oncohematological centres. TP53 mutations were detected using targeted next-generation sequencing. Kaplan-Meier-survival curves and log rank tests were performed to compare survival times between different groups.
Results: We identified 224 TP53 mutations in 25% (127/509) of the patients. High-burden (>10% VAF) mutations represented 39% (n=88) of these alterations, while 61% (n=136) of the TP53 mutations were low-burden. Subclonal mutations as sole alterations were identified in 38% (48/127) of all mutated cases. In 33% of the TP53 mutant cases, we detected multiple mutations with heterogenous sublclonal architecture. In the subcohort of patients treated with chemoimmunotherapy without the implication of targeted agents (n=200), patients with TP53 mutation (n=31) had significantly lower overall survival (OS) as compared to the patients with wild type (n=169) TP53 gene (p=0,009). No significant differences were detected in the OS between patients with low-burden TP53 mutations and wild type cases.
Conclusion: In this study we explored the clonal architecture and clinical impact of low burden TP53 mutations in a nation-wide, “real world” Hungarian patient cohort. Our results demonstrate that patients with sole low-burden TP53 mutations represent more than one third of patients with TP53 aberration, hence the 10% cut-off value might worth reconsidering for TP53 variant reporting in routine diagnostics.
Funding:Horizon2020 739593, K21_137948, FK20_134253, TKP2021-EGA-24 and TKP2021-NVA-15, the EFOP-3.6.3-VEKOP-16-2017-00009 and ÚNKP-21-2-I-SE-21.

University and Doctoral School

Semmelweis University, Doctoral School of Pathological Sciences

Supervisor

Csaba Bödör PhD

Publication of my abstract

I give consent to the publication of my abstract on the website of the congress.

Kind

Szabad

Status

elfogadva

Accepted presentation method

poszter

Előadás fájl jóváhagyás

nem rendelkezett róla

Előadó

6905

Start

10:35

End

10:40

Authors (legacy)

Tamás László1, Lili Kotmayer1, Viktória Fésüs1,2, Csaba Bödör1

1HCEMM-SU Molecular Oncohematology Research Group,Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest
2Kaposi Mór University Teaching Hospital of County Somogy, Kaposvár