Abstract 195P
Background
A better understanding of trends in NACT use and response in pts with early- and operable locally advanced–stage triple-negative breast cancer (eTNBC) can help identify subgroups whose treatment (tx) and outcomes can be improved. We investigated tx patterns and predictors of NACT and pathologic complete response (pCR) in US pts with eTNBC.
Methods
This retrospective observational study of the NCDB included pts with non-metastatic, clinical T1-T4, N0-3, invasive eTNBC diagnosed between 2010 and 2016. Chemotherapy (chemo) type (NACT vs adjuvant chemo [ACT]) was defined using surgery and chemo start dates. pCR was defined as a documented CR to NACT and/or pathologic stage of ypT0/isN0. Recurrence and disease-free survival (DFS) data are not in the NCDB and were not evaluated. We used multivariable logistic regression to identify baseline predictors of NACT and pCR.
Results
Of 7573 pts, 1618 (21%) received NACT and 3888 (51%) received ACT. 22%—most with stage I eTNBC—did not receive any chemo. The remaining 5% did not receive surgery. NACT use increased from 15% in pts diagnosed in 2010 to 30% in 2016, which was not explained by temporal changes in clinical stage. NACT was more common in pts with higher clinical stage, yet was used in only 28% of pts with stage II and 47% with stage III TNBC. ACT and NACT pts had similar education status, income, histology, and tumour grade. Pts who had higher T or N stage, or were younger, Hispanic or treated at an academic facility or outside the Northeast were more likely to receive NACT (vs ACT; all type 3 P values < 0.05). Among NACT recipients, pCR was more likely among those with higher grade tumours (adjusted odds ratio [aOR], 1.80; 95% CI: 1.25, 2.62; 3+ vs 1-2) and lower clinical T stage (aOR, 1.91; 95% CI: 1.16, 3.19; T1 vs T4).
Conclusions
For pts receiving chemo as curative tx for TNBC, ACT remains more common than NACT, but NACT use increased from 2010 to 2016. Clinical characteristics appear to be the main tx decision predictors. In pts who received NACT, pCR was more likely in pts with higher grade tumours and lower tumour burden. The effects of these factors on long-term outcomes such as DFS were not available in this dataset.
Clinical trial identification
Editorial acknowledgement
Medical writing assistance for this abstract was provided by Christopher Lum, of Health Interactions, Inc.
Legal entity responsible for the study
F. Hoffmann-La Roche, Ltd.
Funding
F. Hoffmann-La Roche, Ltd.
Disclosure
M. Kashyap: Non-remunerated activity/ies, medical writing support for this publication: Roche. M. Downer: Shareholder/Stockholder/Stock options, Full/Part-time employment: Roche/GNE. M. Debiasi: Full/Part-time employment: Roche. K. Russell: Full/Part-time employment: Roche. C. Craggs: Full/Part-time employment: Roche/GNE. P. Luhn: Shareholder/Stockholder/Stock options, Full/Part-time employment: Roche/GNE. E. Pollom: Honoraria (self): Accuray; Research grant/Funding (institution): Roche.