Abstract 3739
Background
Endometrial cancer (EC) is one of the most common gynaecological tumours. Tumour mutational burden (TMB) has emerged as a promising predictor to evaluate efficacy to immunotherapy in several kinds of solid tumours. However, the relationship between TMB and genetic features of EC remains unclear.
Methods
Total 50 EC patients including 41 endometrioid adenocarcinoma, 6 uterine serous adenocarcinoma, 1 uterine clear cell carcinoma, 1 endometrial squamous cell carcinoma and 1 endometrial adenosquamous carcinoma were enrolled in this study. The ECs had been classified as FIGO I (n = 14), II (n = 6), III (n = 12), IV (n = 16) and not available (n = 2). FFPE tumour and matched blood samples were collected from patients for NGS-based targeted panel sequencing (450 genes). Genomic alterations and TMB were assessed.
Results
The 50 patients had a median age of 56 years (range, 32-73 years) with a median TMB of 3.8 muts/Mb (interquartile range (IQR), 1.5-13.7 muts/Mb). We found recurrent mutations, including PTEN (64%), PIK3CA (44%), ARID1A (40%), PIK3R1 (36%), TP53 (32%), CHD4 (20%), and KRAS (20%). FGFR2 mutations were occurred in 7 (14%) patients. The most frequently mutated genes in early-stage (FIGO I and II) were PTEN (85%), ARID1A (50%), PIK3R1 (50%), PIK3CA (40%), LRP1B (30%), and CHD4 (30%), while the most common mutations in advanced-stage (FIGO III and IV) were PTEN (46%), PIK3CA (43%), TP53 (43%), ARID1A (36%), PIK3R1 (29%), and KRAS (21%). We also found that all POLE mutations (5/5) occurred in early-stage. Mutations of PIK3R1, CHD4, CTCF, SETD2, PPP2R1A, NF1, BRCA2, ARID1B and POLE were associated with TMB-high (TMB-H, TMB≥10muts/Mb) (P < 0.05 for all). Importantly, all POLE mutations occurred in EC with TMB-H, including two cases of EC with ultrahigh TMB (TMB > 100 muts/Mb). At least one actionable mutation was identified in 86% (43/50) patients.
Conclusions
PI3K signaling pathway genes, PTEN, PIK3CA and PIK3R1 were most frequently mutated in EC. 26% patients (13/50) had TMB-H. POLE mutations likely occurred in early stage and were related with TMB-H, which may provide potential targets for immunotherapy of EC.
Clinical trial identification
Editorial acknowledgement
This study was supported by National Natural Science Foundation of China (Youth fund project, no. 81602267).
Legal entity responsible for the study
The authors.
Funding
National Natural Science Foundation of China (Youth fund project, no. 81602267).
Disclosure
Y. Zhang: Full / Part-time employment: OrigiMed. S. Zhang: Full / Part-time employment: OrigiMed. S. Zhao: Full / Part-time employment: OrigiMed. F. Guo: Full / Part-time employment: OrigiMed. F. Pang: Full / Part-time employment: OrigiMed. L. Zhang: Full / Part-time employment: OrigiMed. X. Dong: Full / Part-time employment: OrigiMed. K. Wang: Full / Part-time employment: OrigiMed. All other authors have declared no conflicts of interest.
Resources from the same session
3608 - Prognostic impact of Body Mass Index (BMI) on overall survival in patients with metastatic breast cancer
Presenter: Khalil SALEH
Session: Poster Display session 2
Resources:
Abstract
2686 - Clinicopathological characteristics, survival and prognostic factors of breast cancer-related microangiopathic haemolytic anemia: a multicenter study
Presenter: Marion Alhenc Gelas
Session: Poster Display session 2
Resources:
Abstract
1565 - Metabolic tumor volume by 18F-FDG PET/CT is an independent prognostic factor in metastatic breast cancer
Presenter: Heekyung Ahn
Session: Poster Display session 2
Resources:
Abstract
4498 - Patient Preferences for breast cancer treatments: A Discrete Choice Experiment from four European countries
Presenter: Thomais Konstantopoulou
Session: Poster Display session 2
Resources:
Abstract
1423 - Palbociclib plus fulvestrant as second- or later-line therapy for patients with locally advanced, inoperable or metastatic HR+/HER2- breast cancer in Germany: Interim results of the INGE-B phase 2 study
Presenter: Diana Lüftner
Session: Poster Display session 2
Resources:
Abstract
2284 - Ventriculoperitoneal Shunt for CNS Metastasis in Breast Cancer: Clinical Outcomes Based on Intrinsic Subtype
Presenter: Hee Kyung Kim
Session: Poster Display session 2
Resources:
Abstract
4598 - Administration of chemotherapy for metastatic breast cancer near the end of life: a population registry study
Presenter: Luisa Edman Kessler
Session: Poster Display session 2
Resources:
Abstract
5706 - Prognostic value of histological growth pattern in patients operated for breast cancer liver metastases
Presenter: Ali Bohlok
Session: Poster Display session 2
Resources:
Abstract
1697 - Illness perceptions, quality of life and mood in metastatic breast cancer patients
Presenter: Isabel Domingues
Session: Poster Display session 2
Resources:
Abstract
1935 - Multidisciplinary Treatments Increases Overall Survival in Patients with Newly Diagnosed Stage IV Breast Cancer:An Analysis of 2010–2014 SEER Data
Presenter: Jian Zhang
Session: Poster Display session 2
Resources:
Abstract