Isolated Loss of PMS2 Expression in Colorectal and Endometrial Tumors Explained with Paired Tumor and Germline Testing

Session:
#111
Date:
Thursday, Apr 12, 2018 10:00am – 11:30am
Conference:
ACMG 2018
Authors:
Beth Souders, Brittany Dougall, Carla Mason, Chia-Ling Gau, PhD, DABMG, Daniel Chen, Kelly Fulk, Melissa Truelson, Monalyn Umali Salvador, Swati Shah

High Ranking

  • This study aimed to describe the results of paired tumor and germline DNA testing of the MMR genes for individuals with tumors demonstrating IL-PMS2 at one laboratory.
  • In this cohort, 67% of tumors demonstrating IL-PMS2 were explained by germline PMS2 or MLH1 mutations, MLH1 promoter hypermethylation, or MMR deficiency due to one somatic MLH1 mutation in the presence of CN-LOH.
  • These data support the importance of adding comprehensive paired tumor and germline MMR gene analyses to the Lynch syndrome testing algorithm which will allow clinicians to further distinguish between sporadic tumors and Lynch syndrome.