Mutation landscape of germline and somatic BRCA1/2 in patients with high-grade serous ovarian cancer

BMC Cancer. 2020 Mar 12;20(1):204. doi: 10.1186/s12885-020-6693-y.

Abstract

Background: Poly (ADP-ribose) polymerase inhibitors targeting BRCA1/2 mutations are available for treating patients with high-grade serous ovarian cancer. These treatments may be more appropriately directed to patients who might respond if the tumor tissue is additionally tested by next-generation sequencing with a multi-gene panel and Sanger sequencing of a blood sample. In this study, we compared the results obtained using the next-generation sequencing multi-gene panel to a known germline BRCA1/2 mutational state determined by conventional Sanger sequencing to evaluate the landscape of somatic mutations in high-grade serous ovarian cancer tumors.

Methods: Cancer tissue from 98 patients with high-grade serous ovarian cancer who underwent Sanger sequencing for germline BRCA1/2 analysis were consecutively analyzed for somatic mutations using a next-generation sequencing 170-gene panel.

Results: Twenty-four patients (24.5%) showed overall BRCA1/2 mutations. Seven patients (7.1%) contained only somatic BRCA1/2 mutations with wild-type germline BRCA1/2, indicating acquired mutation of BRCA1/2. Three patients (3.1%) showed reversion of germline BRCA1 mutations. Among the 14 patients (14.3%) with both germline and somatic mutations in BRCA1/2, two patients showed different variations of BRCA1/2 mutations. The next-generation sequencing panel test for somatic mutation detected other pathogenic variations including RAD51D and ARID1A, which are possible targets of poly (ADP-ribose) polymerase inhibitors. Compared to conventional Sanger sequencing alone, next-generation sequencing-based tissue analysis increased the number of candidates for poly (ADP-ribose) polymerase inhibitor treatment from 17.3% (17/98) to 26.5% (26/98).

Conclusions: Somatic mutation analysis by next-generation sequencing, in addition to germline BRCA1/2 mutation analysis, should become the standard of care for managing women with high-grade serous ovarian cancer to widen the indication of poly (ADP-ribose) polymerase inhibitors.

Keywords: BRCA1/2 mutation; High-grade serous ovarian cancer; Next-generation sequencing; Poly (ADP-ribose) polymerase.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • BRCA1 Protein / genetics*
  • BRCA2 Protein / genetics*
  • Cystadenocarcinoma, Serous / drug therapy
  • Cystadenocarcinoma, Serous / genetics
  • Cystadenocarcinoma, Serous / pathology*
  • DNA-Binding Proteins / genetics*
  • Female
  • Germ-Line Mutation
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Middle Aged
  • Mutation*
  • Neoplasm Grading
  • Ovarian Neoplasms / drug therapy
  • Ovarian Neoplasms / genetics
  • Ovarian Neoplasms / pathology*
  • Poly(ADP-ribose) Polymerase Inhibitors / pharmacology
  • Poly(ADP-ribose) Polymerase Inhibitors / therapeutic use
  • Sequence Analysis, DNA / methods
  • Transcription Factors / genetics*
  • Young Adult

Substances

  • ARID1A protein, human
  • BRCA1 Protein
  • BRCA1 protein, human
  • BRCA2 Protein
  • BRCA2 protein, human
  • DNA-Binding Proteins
  • Poly(ADP-ribose) Polymerase Inhibitors
  • RAD51D protein, human
  • Transcription Factors