Patient-reported outcomes of adjuvant therapy with CDK4/6 inhibitors for HR+/HER2- early breast cancer: a retrospective cohort study

To compare the patient-reported outcomes (PROs) and quality of life in patients with HR+/HER2- early breast cancer (EBC) treated with Ribociclib (RIB) and Abemaciclib (ABE) as adjuvant therapy. A multicenter, retrospective cohort study was conducted in Chinese patients receiving RIB or ABE as adjuvant therapy for HR+/HER2- EBC. PRO data were collected via an electronic questionnaire. The questionnaire was based on the PRO scale for breast cancer patients in China (NCC-BC-A scale), EQ-5D-5 L and safety information of CDK4/6 inhibitors, including six dimensions of physiological function, psychological status, social support, treatment related symptoms, economic dimension and overall self-evaluation. The higher score of the questionnaire, the better quality of life. Between Mar 15, and May 12, 2025, 197 patients completed the survey, including 94 patients who received RIB and 103 patients who received ABE. Overall, 195 patients (99%) were female and two (1%) were male. No difference was observed in baseline characteristics such as age, employment status, medical insurance, and concomitant treatment. The total score of the PRO in RIB group was higher than that in ABE group (187.14 ± 17.57 versus(vs.) 180.66 ± 22.26, p = 0.024). In therapeutic domain, the score was significantly higher in RIB group (34.81 ± 5.29 vs. 32.77 ± 5.51, p = 0.009). Patients in RIB group were less affected by the treatment-related symptoms of diarrhea (3.88 ± 0.53 vs. 2.31 ± 1.33, p < 0.001), fatigue (2.29 ± 0.91 vs. 2.00 ± 1.02, p = 0.038) and alopecia (2.94 ± 1.39 vs. 2.49 ± 1.24, p = 0.018). The overall health status score of RIB group was higher (6.67 ± 1.27 vs. 5.83 ± 1.45, p < 0.001). HR+HER2- EBC patients who received RIB had a better PRO score than those who received ABE. Patients in RIB group experienced less treatment-related adverse reactions, especially diarrhea, fatigue, and alopecia, and had a lower rate of discontinuation/reduction due to adverse events, a better self-evaluation of their overall health status.