In France, more than 1 in 3 women diagnosed with breast cancer (BC) is 70 years old or older. Given the many factors that may impact on the success of treatment in older patients with advanced BC (ABC), treatment feasibility (i.e. receiving the optimal duration of treatment) should be assessed carefully in real life. PALOMAGE is a French prospective multi-center study evaluating palbociclib (PAL) + endocrine therapy (ET) in real life setting in women aged ≥70 with hormone receptors positive (HR+) HER2- ABC, either ET-sensitive with no prior systemic treatment for ABC (cohort A), or ET-resistant (relapse during or < 1 year after the end of adjuvant ET) and/or with prior systemic treatment for ABC (cohort B). Quality of life (EORTC QLQ-C30 and ELD14) and geriatric [G8 and Geriatric-COre DatasEt (G-CODE)] data were collected. This analysis reports on the primary endpoint in cohort B: rate (with 95%CI) of permanent PAL discontinuation at 6 months (mo) for any reason including progression, toxicity, patient's choice, or death. Associations between baseline characteristics (demographic, clinical, geriatric) and discontinuation of treatment at 6 mo were estimated with appropriate statistical tests. From 10/2018 to 07/2020, 406 patients were included in cohort B with: median age 78 years (69-98) (15.8% > 85), 15.8% ECOG performance status (PS) ≥2, 67.8% abnormal G8 score (≤14), 86.7% Charlson score ≥4, 49.3% visceral metastasis (liver 25.9%, lung 27.6%), 24.4% ≥2 lines of systemic treatment for ABC, 52.4% prior chemotherapy. PAL starting dose was 125, 100 and 75 mg in 72.6%, 22.1% and 5.2% of patients, respectively, combined with fulvestrant or an aromatase inhibitor in 65.3% and 34.7%, respectively. The primary endpoint analysis was performed on the full analysis set of cohort B: among 378 eligible and treated patients, 109 (28.8%; 95%CI=24.3-33.7) had a permanent PAL discontinuation at 6 mo due to progression (67 patients/17.7%), toxicity (14 patients/3.7%), death (14 patients/3.7%), or patient's choice (11 patients/2.9%). Treatment discontinuation rate at 6 mo according to PAL starting dose 125/100/75 mg was 28% (95%CI=22.7-33.6), 30.5% (95%CI=20.8-41.6), and 35.3% (95%CI=14.2-61.7), respectively. With a median follow-up of 11.3 mo, 33.6% of patients were still on PAL treatment. Median time to treatment failure (TTF) was 11.6 mo (95%CI=10-13). The G-CODE domains at baseline that were significantly associated with PAL permanent discontinuation at 6 mo were: alteration of autonomy with ADL score ≤5 (p=0.04) and unintentional weight loss >10% in the last 6 mo (p<0.001). PALOMAGE is a unique French real-world study dedicated to older patients treated with PAL for ABC. This is one of the first studies to consider geriatric characteristics with the use of G-CODE. In this cohort B analysis, treatment discontinuation rate at 6 mo was 28.8%, close to what has been observed in PALOMA 3 study, and did not differ according to PAL starting dose. Although not controlled, these data are reassuring and suggest that PAL treatment is feasible in resistant and/or pretreated women aged ≥70. Further analyses (bivariate and multivariate) will be performed on the association between baseline characteristics and treatment discontinuation. Relation with quality of life will also be explored using time until definitive quality of life score deterioration, for example. Breast cancer; Elderly; Real world data; Palbociclib; Geriatric characteristics Les auteurs n'ont pas précisé leurs éventuels liens d'intérêts.