Article Text
Abstract
Introduction/Background*In Slovenia, ovarian cancer is diagnosed in approximately 160 women per year. The majority of patients are diagnosed with advanced disease and the survival rate is poor. 20 – 30% of cases can be attributed to germline pathogenic/likely pathogenic variants (P/LPV) in genes, associated with hereditary breast and ovarian cancer syndrome (HBOC). P/LPV in BRCA1/2 genes are the most prevalent. With the development of new methods for genetic testing, such as next generation sequencing (NGS), associations between non-BRCA genes and HBOCare being discovered.
Methodology We analyzed genetic results of patients with the diagnosis of ovarian, fallopian tube or primary peritoneal cancer, who were concecutively referred for genetic assessment at our institution in the period between September 2014 and April 2021. Since September 2014 all such patients are routinely tested with NGS with a panel (TruSight Cancer panel or TruSight Hereditary Cancer panel) of 19 HBOC genes. In some cases, an analysis of tumor tissue was also performed.
Result(s)*During the observation period, 744 patients were tested for germline P/LPV in HBOC gene panel. P/LPV was found in 226/744 (30.4%) of tested patients. 207/744 (27.8%) of patients had P/LPV in BRCA1/2. Non-BRCA P/LPVs were found in 19 patients (2.6%), one patient had a P/LPV in both ATM and RAD51C genes (figure 1). The most common P/LPVs in non-BRCA genes were detected in ATM gene, and were diagnosed in 6 patients (figure 2). The results of tumor tissue testing were available for 7/19 nonBRCA-positive patients and in 1 biallelic PALB2 inactivation was found.
Conclusion*Among 744 consecutively tested patients with ovarian, fallopian tube or primary peritoneal cancer, we detected a high P/LPV rate (30.4%). 27.8% of all tested patients were diagnosed with BRCA1/2 P/LPVs. P/LPVs in other than BRCA1/2 genes were detected less frequently (2.6%). It is, however, important to be aware that P/LPVs in genes other than BRCA1/2can be detected in patients with ovarian cancer and that these women may also benefit from targeted treatment, preventive measures and further cascade testing in the family. Tumor testing may also reveal new treatment targets and help explain carcinogenesis in these patients.