Abstract 558P
Background
Molecular subtypes of EC is widely recognized and applied in clinics. While, it is still less recognized the distribution and prognostic value of molecular subtypes of endometrial carcinoma in Chinese population. An NGS-based classification strategy with reference to these two classifiers was developed and applied for the first time to explore the prognostic correlation of EC patients in China.
Methods
Formalin-Fixed Paraffin Embedded (FFPE) tissue of 233 EC patients were retrospectively collected from Qilu Hospital, China. Genomic DNA was extracted and subjected to an all-in-one simplified NGS panel covering POLE, TP53 as well as MSI for subtyping. The information for ProMisE classification were also collected. With the median follow-up was 66 (range 7-122) months, overall survival (OS) and disease-specific survival (DSS) were also been analyzed across the subtypes.
Results
Base on NGS panel classification, the fractions of POLE, MSI, CNH and CNL group were 8.15%, 18.88%, 11.59% and 61.37%, respectively. 61patients with ProMisE classification available, the fractions of the former subtypes were11.48%, 36.07%, 14.75%, and 37.70% respectively. The OS and DSS was (P=0.046 for OS, P=0.024 for DSS) significantly in the four subtypes based on NGS testing in 131 followed patients. There was no significant difference in OS (P = 0.91) and DSS (P = 0.95) across the four subtypes by ProMisE in 50 followed patients (Table). Table: 558P
Survival analysis results based on the two classifiers
| NGS-based classifier（N=131） | |||||
| POLE | MSI | CNH | CNL | P | |
| 8 years -OS rate | 100% | 80.00% | 50.00% | 92.26% | 0.046 |
| 8 years -DSS rate | 100% | 88.89% | 66.67% | 100% | 0.024 |
| ProMisE classifier (N=50) | |||||
| 8 years -OS rate | 83.33% | 89.47% | 100% | 80.00% | 0.91 |
| 8 years -DSS rate | 100% | 94.73% | 100% | 92.31% | 0.95 |
Conclusions
The NGS-based strategy was confirmed to effectively classify four prognostically significant subgroups in endometrial cancer patients. Further analysis showed that the clinicopathological features of each molecular subtype were significantly different. All the results confirmed the feasibility of molecular subtyping of EC in clinical practice by a simplified NGS approach.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Qilu Hospital of Shandong University.
Funding
Amoy Diagnostics Co., Ltd.
Disclosure
All authors have declared no conflicts of interest.