Key clinical point: A higher body mass index (BMI) was associated with a lower frequency of hematologic toxicities and, consequently, with a lower rate of treatment discontinuation in women with early-stage hormone receptor-positive (HR+) breast cancer (BC) who received palbociclib + endocrine therapy (ET).
Major finding: In women who received palbociclib, higher BMI was associated with a significantly lower rate of neutropenia (odds ratio for a 1-unit change in BMI 0.93; 95% CI 0.92-0.95) and hence, with a lower rate of treatment discontinuation (adjusted hazard ratio for a 10-unit change in BMI 0.75; 95% CI 0.67-0.83).
Study details: Findings are from an analysis of the PALLAS trial including 5698 patients with early-stage II-III, HR+/human epidermal growth factor receptor 2-negative BC who were randomly assigned to receive adjuvant ET for ≥ 5 years with or without palbociclib for 2 years.
Disclosures: This study was supported by Pfizer and other sources. Two authors declared being employees and stockholders of Pfizer. The other authors reported ties with several sources, including Pfizer.
Source: Pfeiler G et al on behalf of the PALLAS Groups and Investigators. Impact of BMI in patients with early hormone receptor-positive breast cancer receiving endocrine therapy with or without palbociclib in the PALLAS trial. J Clin Oncol. 2023 (Aug 9). doi: 10.1200/JCO.23.00126