24P - Germline genetic testing for hereditary cancer: A retrospective analysis in a single site referral centre in Malaysia

Background

Genetic testing for hereditary cancer is important for clinical treatment and risk management for patients and high-risk individuals. The landscape of genetic testing for germline cancer predisposition has shifted from single gene testing to the more cost-effective multi-gene panels. However, multi-gene panel testing results in greater variant of uncertain significance (VUS) rates and secondary findings, which is challenging for clinical management. In this study, we aim to describe the genetic testing uptake and variant distribution in a single genetic counselling and testing centre in Malaysia.

Methods

A descriptive retrospective analysis of patients seen at a single genetic counselling and testing centre was conducted. Patients were referred from clinicians or self-referred from January 2019 until December 2022. Researchers conducted intake calls, collected pedigrees and written informed consent from all patients prior to genetic testing. Pre and post-test genetic counseling was provided by the certified genetic counselor. Patients were offered either physical consultation or telegenetic counselling. Multi-gene panels were used to analyze between 19 to 47 genes which are associated with an increased risk of hereditary cancer.

Results

Among the 489 who were referred, 430 (88%) came forward for genetic counseling, the majority of them were referred from private hospitals within the Klang Valley. Among the 381 (89%) who proceeded with genetic testing, 13.9% had pathogenic/likely pathogenic variants, 24.4%, variant of uncertain significance and 61.7% had no variants detected. Majority of the patients had breast cancer (77%) and 84% met current genetic testing guidelines criteria.

Conclusions

The uptake rate of genetic testing is high after pre-test genetic counselling. However, there is a high rate of VUS which causes uncertainties for the patients and their clinicians in making clinical management decisions. Adequate pre and post-test genetic counseling can ensure a better understanding of these variants’ implication and provide support of potential psychosocial impact to the patient.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Cancer Research Malaysia.

Funding

Has not received any funding.

Disclosure

The author has declared no conflicts of interest.