Abstract 312P
Background
Poly(ADP-ribose) polymerase inhibitors (PARPi) are available as targeted treatments for pts with germline BRCA1/2mut HER2− ABC. Recently, international guidelines have broadened the eligibility criteria for germline BRCA1/2mut testing. Limited information exists on RW BRCA1/2mut testing rates since the approval of PARPi. This study assessed trends in BRCA1/2mut testing (germline and/or somatic) among HER2− ABC pts in the US, and France, Germany, Italy, and Spain (EU4).
Methods
Oncologists (ONCs) abstracted data from medical charts for the next 8-10 presenting pts with HER2− ABC over three waves of data collection (Feb-May 2015, Mar-Jul 2017, Sept 2019-Apr 2020). BRCA1/2mut testing rates were stratified by region and hormone receptor (HR) status (HR+/HER2−, triple-negative breast cancer [TNBC]), and compared by year of data collection via Fisher’s exact tests.
Results
7,665 records were provided by 913 ONCs (2015 n=2,827; 2017 n=2,420; 2019/2020 n=2,418). Across all years, mean age was 63.3 years; 77% HR+/HER2−, 20% TNBC, 3% unknown HR status. Across US and EU4, a significant decline in BRCA1/2mut testing rates were observed among HR+/HER2− pts between the years 2015 and 2017. A significant increase in BRCA1/2mut testing rates was observed between the years 2017 and 2019/2020 among US and EU4 HR+/HER2− and TNBC pts.
Conclusions
BRCA1/2mut testing rates declined between 2015 and 2017 among HR+/HER2− pts. This may be due to the availability of CDK4/6 inhibitors, which can be used regardless of BRCA mutation status. BRCA1/2mut testing increased in 2019/2020 for HR+/HER2− and TNBC pts, coinciding with availability of PARPi. Further opportunities to increase BRCA1/2mut testing exist, especially in Europe and/or among HR+/HER2− pts. Studies evaluating germline-specific BRCA1/2mut testing trends are warranted. Table: 312P
| 2015 | 2017 | 2019/2020 | P-value 2015 vs. 2017 | P-value 2015 vs. 2019/2020 | P-value 2017 vs. 2019/2020 | |
| EU4 HR+/HER2− BRCA1/2 tested, n (%) | N=1,518 393 (26) | N=1,412 192 (14) | N=1,703 631 (37) | < 0.001 | < 0.001 | < 0.001 |
| EU4 TNBC BRCA1/2 tested, n (%) | N=568 193 (34) | N=364 115 (32) | N=223 174 (78) | 0.476 | < 0.001 | < 0.001 |
| US HR+/HER2− BRCA1/2 tested, n (%) | N=470 238 (51) | N=493 178 (36) | N=325 222 (68) | < 0.001 | < 0.001 | < 0.001 |
| US TNBC BRCA1/2 tested, n (%) | N=171 121 (71) | N=124 90 (73) | N=82 76 (93) | 0.794 | < 0.001 | < 0.001 |
Clinical trial identification
Editorial acknowledgement
Medical writing support was provided by Ann Gordon, of CMC AFFINITY, McCann Health Medical Communications, and was funded by Pfizer.
Legal entity responsible for the study
Pfizer.
Funding
Pfizer.
Disclosure
R. Mahtani: Research grant/Funding (self): Genentech; Advisory/Consultancy: Pfizer; Advisory/Consultancy: Eli Lilly; Advisory/Consultancy: Novartis; Advisory/Consultancy: Celgene; Advisory/Consultancy: Eisai; Advisory/Consultancy: AstraZeneca; Advisory/Consultancy: Puma; Advisory/Consultancy: Amgen; Advisory/Consultancy: Daiichi-Sankyo; Advisory/Consultancy: Seattle Genetics. A. Niyazov: Shareholder/Stockholder/Stock options, Full/Part-time employment: Pfizer Inc.. K. Lewis: Full/Part-time employment: Adelphi Real World. L. Massey: Full/Part-time employment: Adelphi Real World. A. Rider: Full/Part-time employment: Adelphi Real World. B. Arondekar: Shareholder/Stockholder/Stock options, Full/Part-time employment: Pfizer Inc.. M.P. Lux: Honoraria (self), Advisory/Consultancy, fees for non-CME services : Eli Lilly; Honoraria (self), Advisory/Consultancy, fees for non-CME services : AstraZeneca; Honoraria (self), Advisory/Consultancy, fees for non-CME services : MSD; Honoraria (self), Advisory/Consultancy, fees for non-CME services : Novartis; Honoraria (self), Advisory/Consultancy, Travel/Accommodation/Expenses, fees for non-CME services : Pfizer; Honoraria (self), Advisory/Consultancy, fees for non-CME services : Eisai; Honoraria (self), Advisory/Consultancy, fees for non-CME services : Genomic Health; Honoraria (self), Advisory/Consultancy, Travel/Accommodation/Expenses, fees for non-CME services : Roche; Honoraria (self), Advisory/Consultancy: Hexal ; Honoraria (self), Advisory/Consultancy, Officer/Board of Directors: Medac.