Next generation sequencing reveals a high prevalence of pathogenic mutations in homologous recombination DNA damage repair genes among patients with uterine sarcoma

Objective: Investigate the incidence of homologous recombination DNA damage response (HR-DDR) genomic alterations among patients with uterine sarcoma.

Methods: The American Association for Cancer Research GENIE v13.0 database was accessed and patients with uterine leiomyosarcoma, adenosarcoma, undifferentiated uterine sarcoma, high-grade endometrial stromal sarcoma, low-grade endometrial stromal sarcoma, and endometrial stromal sarcoma not otherwise specified were identified. We determined the incidence of pathogenic alterations in the following genes involved in HR-DDR: ATM, ARID1A, ATRX, BAP1, BARD1, BLM, BRCA2, BRCA1, BRIP1, CHEK2, CHEK1, FANCA, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCL, MRE11, NBN, PALB2, RAD50, RAD51, RAD51B, RAD51C, RAD51D, WRN. Data from the OncoKB database, as provided by cBioPortal, was utilized to determine the presence of pathogenic genomic alterations.

Results: A total of 509 patients contributing with 525 samples were identified. Median patient age at sample collection was 56 years while the majority were White (80.7%). The most common histologic subtype was leiomyosarcoma (63.8%) followed by adenosarcoma (12.3%). The overall incidence of HR-DDR genomic alterations was 28.2%. The most commonly altered genes were ATRX (18.2%), BRCA2 (4%), and RAD51B (2.6%). The highest incidence of HR-DDR genomic alterations was observed among patients with leiomyosarcoma (35.4%), adenosarcoma (27%) and undifferentiated uterine sarcoma (30%), while those with low-grade endometrial stromal sarcoma had the lowest (2.9%) incidence.

Conclusions: Approximately 1 in 3 patients with uterine sarcoma harbor a pathogenic alteration in HR-DDR genes. Incidence is high among patients with uterine leiomyosarcoma and adenosarcoma.