Findings of UTS for LS in an Integrated Healthcare System

Abstract

Introduction: Lynch syndrome (LS) is associated with an increased risk of colorectal (CRC) and endometrial (EC) cancers. Universal tumor screening (UTS) of all patients diagnosed with CRC and EC is recommended to increase identification of LS. Kaiser Permanente Northwest (KPNW) implemented a UTS program for LS among individuals newly diagnosed with CRC in January 2016 and EC in November 2016. Screening includes immunohistochemistry (IHC) of mismatch repair proteins associated with LS, followed by reflex testing, if indicated, to rule out likely sporadic cases.Materials and methods: Individuals newly diagnosed with CRC and EC were identified between the start of the respective screening programs and July 2018. Electronic medical records were reviewed to extract patient data related to tumor screening, including IHC and reflex testing results, date of referrals to the genetics department, and genetic testing results. Results: 344 out of 400 CRC patients and 66 out of 69 EC patients who were eligible were screened for LS. Most (53/59 or 90%, including 52/56 CRC and 1/3 EC) individuals that were not screened only had a biopsy sample available. Fifteen individuals (3.6% overall, including 14/344 CRC and 1/66 EC) received an abnormal screen result after reflex testing and were referred for genetic counseling. Of these, 11 individuals (82% overall, including 10/14 CRC and 1/1 EC) underwent genetic testing. Six CRC patients were found to have pathogenic variants. Conclusion: The UTS programs assist in identifying LS in KPNW patients. Timing of screening (i.e., soon after surgery for CRC) was not a significant barrier for follow-up. There are opportunities for improvement, such as consistent use of biopsy samples for screening.