# Enhancing the interpretation of real-world quality of life in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer enrolled in the POLARIS study

## TL;DR

The study shows that patients with a specific type of breast cancer report improved quality of life after starting palbociclib treatment, with these improvements lasting up to 18 months.

## Contribution

A novel interpretation framework for quality of life scores in breast cancer patients using real-world data from the POLARIS study.

## Key findings

- Favorable global health status scores increased by ~13% at month 6 and remained stable through month 18.
- Quality of life scores improved by ~9% at month 6 and were maintained in most subgroups.
- High completion rates of quality of life assessments were observed in the real-world patient population.

## Abstract

Patient-reported outcomes are recommended clinical outcome assessments of quality of life (QoL) by patient advocacy groups and regulatory agencies to gain a better understanding of treatment effectiveness, tolerability and safety.

In this study, we aimed to enhance and contextualize the interpretation of patient-reported scores on global health status (GHS) and QoL from the EORTC QLQ−C30 questionnaire into more meaningful terms using data from POLARIS.

Patients ≥ 18 years of age who had a diagnosis of hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2−) advanced/metastatic breast cancer (ABC/mBC) were enrolled in the prospective, observational, multicenter, real-world POLARIS study.

Patients received palbociclib plus endocrine therapy as first-line, second-line or later line of therapy.

Proportions of patients with “favorable” (numeric scores 5−7) and “unfavorable” (numeric scores ≤ 4) responses were determined at baseline and months 6, 12, and 18.

Between January 2017 and January 2023, 1250 patients were enrolled and received ≥ 1 palbociclib dose. EORTC QLQ−C30 GHS/QoL domain completion rates were 93.4%, 66.5%, 49.5%, and 42.3% at baseline and months 6, 12, and 18, respectively. For Question 29 (GHS), the proportion of patients with a favorable response significantly increased by ∼13% to 69.3% by month 6, which was maintained at month 12 (68.6%) and month 18 (70.0%). For Question 30 (QoL), the proportion of patients with a favorable response significantly increased by ∼9% to 74.5% by month 6, which was maintained at month 12 (75.0%) and month 18 (73.4%).

The proportions of patients with HR+/HER2− ABC/mBC indicating a favorable response on GHS and QoL questions of the EORTC QLQ−C30 increased early on after the start of palbociclib treatment and were preserved through month 18 across the overall study population and most evaluated subgroups. This simple interpretation of GHS and QoL scores is intended to enhance their meaning to benefit patients and other stakeholders.

NCT03280303; registered September 12, 2017.