Article Text
Abstract
Introduction/Background Since 2016 routine Lynch syndrome screening (LSS) among women with endometrial cancer <70 years of age has been incorporated in a nationwide guideline. LSS consists of immunohistochemical (IHC) staining for loss of miss match repair (MMR) protein expression, extended with methylation analysis of the MLH1 promotor in case of MLH1 and PMS2 loss. Test results are discussed by the treating gynaecologist, who refers patients to a genetic counsellor (figure 1).
Objective Evaluate the implementation of the Dutch guideline to screen women with endometrial carcinoma under the age of 70 years for Lynch syndrome.
Methodology From the pathology database women diagnosed with EC <70 years of age, treated from 1.6.2016 - 1.6.2017, in 14 hospitals, covering about 30% of the Netherlands, were selected. Data collected regarded LS testing and outcome, and follow up. The study was approved by the institutional review boards of participating hospitals.
Results In 184 out of the 205 tumours (90%) LSS was performed (table 1). Either on the endometrial biopsy 24%, the hysterectomy (70%), or on both (6%). In 42 cases (22%) MMR protein expression was lost, in 25 cases due to hypermethylation of the MLH1 promotor. LS susceptibility was discussed with 11 of the 17 patients at risk of LS (65%), all were referred for genetic counselling. Three of them declined; eight underwent germline testing for LS after counselling. In one no germline mutation was detected, two were diagnosed with a PMS2 mutation, and five with a MSH6 mutation.
Conclusion The implementation of the guideline regarding LSS has been successful, though referral for genetic counselling should be improved. Gynaecologist ought to be aware of the benefits and drawbacks of knowing mutational status, and may require training in discussing this with their patients.
Disclosure Nothing to disclose.
Outcomes
Nationwide dutch guideline for detecting lynch syndrome (LS) in women with endometrial cancer