Unknown

Dataset Information

0

The Genomic Landscape of Early-Stage Ovarian High-Grade Serous Carcinoma.


ABSTRACT:

Purpose

Ovarian high-grade serous carcinoma (HGSC) is usually diagnosed at late stage. We investigated whether late-stage HGSC has unique genomic characteristics consistent with acquisition of evolutionary advantage compared with early-stage tumors.

Experimental design

We performed targeted next-generation sequencing and shallow whole-genome sequencing (sWGS) on pretreatment samples from 43 patients with FIGO stage I-IIA HGSC to investigate somatic mutations and copy-number (CN) alterations (SCNA). We compared results to pretreatment samples from 52 patients with stage IIIC/IV HGSC from the BriTROC-1 study.

Results

Age of diagnosis did not differ between early-stage and late-stage patients (median 61.3 years vs. 62.3 years, respectively). TP53 mutations were near-universal in both cohorts (89% early-stage, 100% late-stage), and there were no significant differences in the rates of other somatic mutations, including BRCA1 and BRCA2. We also did not observe cohort-specific focal SCNA that could explain biological behavior. However, ploidy was higher in late-stage (median, 3.0) than early-stage (median, 1.9) samples. CN signature exposures were significantly different between cohorts, with greater relative signature 3 exposure in early-stage and greater signature 4 in late-stage. Unsupervised clustering based on CN signatures identified three clusters that were prognostic.

Conclusions

Early-stage and late-stage HGSCs have highly similar patterns of mutation and focal SCNA. However, CN signature analysis showed that late-stage disease has distinct signature exposures consistent with whole-genome duplication. Further analyses will be required to ascertain whether these differences reflect genuine biological differences between early-stage and late-stage or simply time-related markers of evolutionary fitness. See related commentary by Yang et al., p. 2730.

SUBMITTER: Cheng Z 

PROVIDER: S-EPMC7612959 | biostudies-literature |

REPOSITORIES: biostudies-literature

Similar Datasets

| S-EPMC9048792 | biostudies-literature
| EGAS00001005567 | EGA
| S-EPMC10359414 | biostudies-literature
| S-EPMC5547474 | biostudies-literature
| S-EPMC2933510 | biostudies-literature
| S-EPMC10478425 | biostudies-literature
| S-EPMC7823988 | biostudies-literature
| S-EPMC7723336 | biostudies-literature
| S-EPMC9738935 | biostudies-literature
| S-EPMC8391231 | biostudies-literature