Table 2.

Characteristics of cfDNA BRCA1/2 mutations.

Characteristics of cfDNA BRCA1/2 mutations (N = 29, overall cohort)
CharacteristicNumber of patients
BRCA1 or BRCA2BRCA1: 15 (51.7%)
BRCA2: 11 (37.9%)
Both BRCA1 and BRCA2: 3 (10.3%)
Previously known germline pathogenic vs. novel variantsKnown germline pathogenic: 9 (31%)
Novel variants: 20 (69%)
Clonal vs. subclonalClonal: 16 (45.7%)
Subclonal: 19 (54.3%)
Prior platinum or anthracycline treatment before cfDNA testingPrior platinum: 4 (13.8%)
Prior anthracycline: 16 (55.2%)
None: 11 (37.9%)
Coexisting germline BRCA1/2 mutationGermline BRCA1 mutation: 1 (3.4%)
Germline BRCA2 mutation: 0 (0%)
No known germline BRCA1 or BRCA2 mutation: 28 (96.6%)
Coexisting BRCA1/2 mutation detectable by tumor tissue genotypingBRCA1: 3 (15.8%)
BRCA2: 0 (0%)
No BRCA1 or BRCA2 mutation detected by tumor tissue genotyping: 16 (84.2%)
Characteristics of cfDNA previously known germline pathogenic BRCA1/2 mutations (N = 9)a
BRCA1 or BRCA2BRCA1: 5 (55.6%)
BRCA2: 3 (33.3%)
Both BRCA1 and BRCA2: 1 (11.1%)
Clonal vs. subclonalClonal: 4 (44.4%)
Subclonal: 5 (55.6%)
Prior platinum or anthracycline treatment before cfDNA testingPrior platinum: 4 (44.4%)
Prior anthracycline: 5 (55.6%)
None: 2 (22.2%)
Coexisting germline BRCA1/2 mutationGermline BRCA1 mutation: 1 (11.1%)
Germline BRCA2 mutation: 0 (0%)
No known germline BRCA1 or BRCA2 mutation: 8 (88.9%)
Coexisting BRCA1/2 mutation detectable by tumor tissue genotypingBRCA1: 2 (40%)
BRCA2: 0 (0%)
No BRCA1 or BRCA2 mutation detected by tumor tissue genotyping: 3 (60%)
Characteristics of cfDNA novel variant BRCA1/2 mutations (N = 20)a
BRCA1 or BRCA2BRCA1: 10 (50.0%)
BRCA2: 5 (25.0%)
Both BRCA1 and BRCA2: 5 (25.0%)
Clonal vs. subclonalClonal: 10 (50.0%)
Subclonal: 10 (50.0%)
Prior platinum or anthracycline treatment before cfDNA testingPrior platinum: 0 (0%)
Prior anthracycline: 11 (55.0%)
None: 9 (45.0%)
Coexisting germline BRCA1/2 mutationGermline BRCA1 mutation: 0 (0%)
Germline BRCA2 mutation: 0 (0%)
No known germline BRCA1 or BRCA2 mutation: 20 (100%)
Coexisting BRCA1/2 mutation detectable by tumor tissue genotypingBRCA1: 1 (6.7%)
BRCA2: 0 (0%)
No BRCA1 or BRCA2 mutation detected by tumor tissue genotyping: 14 (93.3%)
  • aFor these analyses, patients with both known germline pathogenic and novel variants in cfDNA were included in the known germline pathogenic category.