PALBOCICLIB RESPONSE IN IRAQI PATIENTS WITH METASTATIC BREAST CANCER, CLINICAL PRACTICE
DOI:
https://doi.org/10.22159/ajpcr.2026v19i2.57670Keywords:
metastatic breast cancer, hormone receptor positive, palbociclib, Real-world evidence, Cyclin-dependent kinases 4 / 6 inhibitor.Abstract
Objectives: To evaluate palbociclib, a novel small molecule inhibitor of cyclin-dependent kinases 4 and 6, in the treatment of hormone receptor-positive/human epidermal growth factor receptor 2 (HR+/HER2−) advanced breast cancer (CA) Iraqi patients.
Methods: One hundred forty female patients with advanced breast CA were enrolled in this prospective cohort study, treated with palbociclib in combination with endocrine therapy.
Results: The mean age of the patients analyzed was 53.51 years (range 23–70). 72.1% were postmenopausal women and 27.9% premenopausal. 56.4% had visceral metastasis, whereas 21.4% of patients had bone-only disease. An overall objective response rate of 36.4% was detected, with 22.9% complete responses and 13.6% partial responses. Stable disease was achieved by 28 patients (20%) with an overall clinical benefit rate (CBR) of 56.4%. There was a difference among biological and clinical demographic characteristics parameters among the treatment response groups that is statistically insignificant, with the exception of the hormonal status parameter, which shows statistical significant difference.
Conclusion: The response to palbociclib treatment in Iraqi patients with HR+/HER2− metastatic breast CA in the form of CBRs, an overall response rate, as well as the factors affecting this treatment, was comparable to that reached by studies in the world (PALOMA-2 and PALOMA-3).
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