{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T08:02:58Z","timestamp":1790150578327,"version":"4.0.1"},"reference-count":35,"publisher":"Pan African Medical Journal","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pan Afr Med J"],"abstract":"<jats:p>Introduction: cyclin-dependent kinase 4\/6 inhibitors (CDK4\/6is) are widely used to treat hormone receptor-positive\/human epidermal growth factor receptor 2-negative (HR+\/HER2-) metastatic breast cancer (MBC). This study aimed to assess the real-world efficacy and tolerability of CDK 4\/6i in the Egyptian population.\n\n \n\nMethods: prospective observational study for HR+\/HER2- MBC treated in the clinical oncology department of Ain Shams University Hospitals, Egypt, between July 2022 and September 2024.\n\n \n\nResults: sixty-two patients were included (mean age, 53.8 years; range, 29-85). Thirty-one (50%) received CDK4\/6is as first-line therapy and 31 as second-line therapy. Median follow-up time was 14.2 months (range 12-24 months). Thirty patients (48.3%) started on Ribociclib, 9 (14.5%) on Abemaciclib, and 23 (37.1%) on Palbociclib, with 15 patients switched from Ribociclib and Abemaciclib to Palbociclib due to logistical causes. Median progression-free survival (PFS) was 14 months (6-27 months) and 11 months for first- and second-line therapy, respectively. Patients and treatment characteristics did not significantly impact PFS. Ribociclib and Palbociclib most frequently caused neutropenia (70.0% and 68.4%, respectively), while Abemaciclib caused diarrhea (55.6%). The rate of dose reductions was 24.6%. Age was significantly correlated with a higher incidence of hematological (p=0.03) and nephrological toxicity (p=0.02). Furthermore, medical comorbidities were associated with a significantly higher frequency of grade 3-4 hematological events (p=0.02).\n\n \n\nConclusion: our findings demonstrate that CDK4\/6is are both effective and well-tolerated for HR+\/\/HER2- MBC patients within a diverse patient population. Additionally, this prospective evaluation supports the efficacy of lower-dose levels of CDK4\/6is, without negatively impacting PFS.<\/jats:p>","DOI":"10.11604\/pamj.2026.53.121.49258","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T07:18:08Z","timestamp":1790147888000},"source":"Crossref","is-referenced-by-count":0,"title":["Clinical outcomes and toxicity in metastatic breast cancer patients treated with first or second-line cyclin-dependent kinase (CDK) 4\/6 inhibitors and endocrine therapy in Egypt"],"prefix":"10.11604","author":[{"given":"Hesham Mahmoud","family":"ElWakeel","sequence":"first","affiliation":[{"name":"Clinical Oncology and Nuclear Medicine Department, Ain Shams University, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hagar Ibrahim","family":"Elghazawy","sequence":"additional","affiliation":[{"name":"Clinical Oncology and Nuclear Medicine Department, Ain Shams University, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nagy Samy","family":"Gobra","sequence":"additional","affiliation":[{"name":"Clinical Oncology and Nuclear Medicine Department, Ain Shams University, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asmaa Ali","family":"Kortoma","sequence":"additional","affiliation":[{"name":"Clinical Oncology and Nuclear Medicine Department, Ain Shams University, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"4870","published-online":{"date-parts":[[2026,3,11]]},"reference":[{"key":"ref0","doi-asserted-by":"crossref","unstructured":"Ferlay J, Colombet M, Soerjomataram I, Parkin DM, Pi\u00f1eros M, Znaor A et al. 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