Objective:

Cyclin-dependent kinase 4/6 inhibitors have a synergistic effect in combination with endocrine therapy. This combination is used as first and subsequent-line treatment for advanced luminal breast carcinoma because it increases progression-free survival. We analysed clinical course and toxicity in patients treated with palbociclib in our hospital and determined potential associations between these variables and clinicopathological variables.

Method:

Observational retrospective study including patients with advanced or metastatic breast cancer treated with palbociclib plus endocrine therapy at the Hospital Universitario de Cabueñes between 2017 and 2020. We analysed clinicopathological variables, toxicity, and survival.

Results:

In total, 72 women and 1 man (median age: 63 years) received palbociclib plus an aromatase inhibitor or fulvestrant. When used as firstline treatment, progression-free survival was 22 months, and as second and subsequent-line treatment, progression-free survival was 13 months. Adverse effects (mainly haematological) were experienced by nearly all patients (95.9%). Treatment was not discontinued because of toxicity in any patient, although delays and dose adjustments were common (61.7% and 42.7%, respectively). Performance status alone had a significant impact on progression-free survival (22 months in patients with ECOG 0 vs 12 months in patients with ECOG ≥ 1; P = 0.021).

Conclusions:

Disease stage, age, and performance status do not limit the use of treatment with palbociclib, nor its combination with aromatase inhibitors or fulvestrant for first or subsequent-line treatment. Toxicity is easily managed. Real-world results are equivalent to those published to date.