Prevalence of BRCA1 and BRCA2 pathogenic and likely pathogenic variants in non-selected ovarian carcinoma patients in Brazil

Deborah Porto Cotrim,
Adriana Regina Gonçalves Ribeiro,
Daniele Paixão,
Diogo Cordeiro de Queiroz Soares,
Rima Jbili,
Natasha Carvalho Pandolfi,
Camila Cezana,
Carine de Cássia Mauro,
Henrique Mantoan,
Graziele Bovolim,
Louise de Brot,
Giovana Tardin Torrezan,
Dirce Maria Carraro,
Glauco Baiocchi,
Maria Nirvana da Cruz Formiga and
Alexandre A. B. A. da CostaEmail author View ORCID ID profile

BMC Cancer201919:4

https://doi.org/10.1186/s12885-018-5235-3

Received: 18 September 2018
Accepted: 19 December 2018
Published: 3 January 2019

Open Peer Review reports

Abstract

Background

BRCA1/2 pathogenic (P) and likely pathogenic (LP) germline variants are frequent among patients with ovarian carcinoma. However, these variants have not been extensively characterized in patients with ovarian cancer in Brazil.

Methods

In this retrospective study we evaluated clinical characteristics and BRCA1/2genetic test results from patients with ovarian carcinoma who underwent genetic counseling at A.C.Camargo Cancer Center (Brazil) between 2015 and 2017 and had performed germline genetic testing of BRCA1/2 genes.

Results

Among 158 patients, 33 P and LP variants and were found (20.8%), 27 in BRCA1and six in BRCA2, and six variants of unknown clinical significance (VUS). Thirteen percent of the patients did not have Multiplex Ligation-dependent Probe Amplification (MLPA) results. Three P variants in BRCA1 were found in more than one patient: c.5266dupC (p.Gln1756Profs*74), c.3331_3334delCAAG (p.Gln1111Asnfs5*), and c.211A > G (p.Arg71Gly). One LP variant in BRCA1 had not been previously described, c.4153_4154delCT (p.Leu1385Ilefs*5). Patients with previous diagnosis of breast cancer were carriers of P or LP variant in 8 of 12 cases (66.7%), and patients with a family history of ovarian or breast cancer in first- or second-degree relatives were carriers of P or LP variant in 26.7% of cases compared to 16.9% for patients without family history (p = 0.166).

Conclusion

Prevalence of BRCA1/2 germline P and LP variants is slightly higher than previously described by the largest occidental studies, with a high prevalence of variant c.5266dupC (p.Gln1756Profs*74) in BRCA1 observed. Moreover, we identified a new LP variant.