Our study has shown that while the genetic predisposition for many early onset ovarian cancers is still unknown, MSH2 is the most important EOC predisposition gene at age <35 years.
The cumulative likelihood of an EOC in MSH2 heterozygotes would appear to be >2% by 35, with this likelihood still below 0.5% for BRCA1 and rare for BRCA2; indeed, two-thirds of cases identified in BRCA2carriers may not have been driven by HRD.
This increased incidence despite the good long-term survival in MSH2 should prompt awareness of the increased risk and consideration for early risk-reduction strategies.
(Flaum N, Crosbie EJ, Woodward ER, et al MSH2 is the very young onset ovarian cancer predisposition gene, not BRCA1 Journal of Medical Genetics Published Online First: 09 March 2023. doi: 10.1136/jmg-2022-109055)
https://jmg.bmj.com/content/early/2023/03/08/jmg-2022-109055.share
Lynch Syndrome Ireland 