Article Text
Abstract
Background and Importance Breast cancer is among the most frequent cancers worldwide. Standard of care for locally advanced or metastatic luminal breast cancer is a cyclin-dependent kinase inhibitor (CKI) (abemaciclib, palbociclib, ribociclib) plus endocrine therapy. All three have shown efficacy and safety in clinical trials, but real-life effectivity and safety data is required.
Aim and Objectives - To determine real-life progression-free survival (PFS) amongst patients treated with abemaciclib, palbociclib and ribociclib.
- To describe their safety profile.
Material and Methods Unicentric, observational and retrospective study, including patients from 11/2017 to 12/2021. No exclusion criteria. Variables obtained: age, gender, treatment start and end dates, reason for treatment termination, adverse events (AE) and severity evaluated by CTCAE criteria.
Descriptive statistical analysis percentages for qualitative results and mean, standard deviation (SD) and ranks for quantitative ones. PFS estimated with Kaplan-Meier method, statistical significance being p<0,05.
Results Patients included: 103, 102(99%) women. Characteristics displayed at table 1:
At study end, 50.5% had suffered disease progression, while 13.6% had discontinued due to toxicity, 4.9% to death, 1% to personal choice and 3.9% to other reasons; 26.2% still ongoing. Median PFS was 9.8 months (table 1), without statistically significant differences among the three drugs (ribociclib-abemaciclib: p=0,055; abemaciclib-palbociclib: p=0,12; ribociclib-palbociclib: p=0,296). Ribociclib presented the longest PFS and abemaciclib the shortest one.
Safety results are shown in table 2:
Conclusion and Relevance No statistically significant differences were found among abemaciclib, palbociclib and ribociclib PFS. While PFS is lower than reported in clinical trials, safety profile is similar, being neutropenia, fatigue and diarrhoea the most common AE. Study limitations include the reduced sample size and its retrospective and unicentric character.
Conflict of Interest No conflict of interest