Hereditary breast and ovarian cancer (HBOC) is one of the most frequent disorders among other cancers, caused by presence of germline pathogenic variants in patients. Awareness about presence of actionable mutations (BRCA1,2, ATM and others) is beneficial for patients with breast and ovarian cancer due to possibility of targeted treatment, monitoring risk groups among healthy carries and other aspects. In this study we reveal and characterize pathogenic germline mutations in HBOC patients from different regions in Russian Federation.
Individuals with “family history” were chosen to be included in this study according to the following criteria: (1) young age of disease onset, (2) the presence of relatives with breast or ovarian cancer diagnosis. Information about nationality, age at diagnosis, family cancer history, estrogen, progesterone and Her2 receptor status was collected. The NimbleGen SeqCap EZ Choice kit (“Roche”) was used for target enrichment, and sequencing was performed using Illumina MiSeq (“Illumina”) using paired-end 2 × 251 nucleotide single-index sequencing. HGMD Professional 2017.4 and BIC databases were used to identify pathogenic mutations.
568 patients with breast or ovarian cancer aged from 21 to 82 years old were included in this study. 103 woman has their first cancer diagnosis before 40 years old, 305 – between 40 and 60 years old, 160 - were older than 60. 193 patients had first degree kinship relatives suffered from HBOC syndrome and 165 patients had relatives with other cancers. Of the 568 patients, 22,5% (128) carried pathogenic or likely pathogenic mutation in BRCA1 gene, 9,2% (52) in BRCA2 gene, 17,6% (100) in one of other HBOC related genes, including CDK12, ATM, CDH1, APC, FANCI, CHEK2, FANCL, BARD1, RAD51C, MUTYH, RAD51D, PALB2, FANCA, XRCC2, RAD54L, CHEK1.
Among patients with fulfilling NCCN criteria of hereditary breast or ovarian cancer, only 30% of cases might be explained by BRCA1 or BRCA2 mutation. Panel sequencing is powerful strategy to find variants in other genes, which may play a role in cancer development. It has to be noted that many variants in non-BRCA genes were identified is of unknown significance (VUS) due to absence of database with common variants for Russian population.
Tatarstan Cancer Center.
The work is supported by the Russian Foundation for Basic Research № 18-415-160009 r_a and according to the Russian Government Program of Competitive Growth of Kazan Federal University.
All authors have declared no conflicts of interest.