Efficacy and Safety of Lapatinib in Elderly Egyptian Patients with Her2 neu Positive Metastatic Breast Cancer

Introduction: The efficacy and safety of the lapatinib based treatment remain challenging in elderly patients with her2neu positive metastatic breast cancer (MBC). Lapatinib exhibits a good overall tolerance, but no study has yet been dedicated to elderly women. The present study is a real-world study that aimed to determine the efficacy and tolerability of the lapatinib-based treatment in the first line setting in Egyptian patients with HER2neu positive MBC who cannot get access to trastuzumab. Patients and Methods: In this retrospective study, 60 elderly patients (⩾ 65 years) with her2neu positive MBC and treatment naïve were included. All patients were treated with the combination of lapatinib (1,250 mg/day, continuously) and chemotherapy (either capecitabine 2,000 mg/m2 on days 1–14 of a 21-day cycle or weekly taxol 80 mg/m2), or lapatinib (1,250 mg/day, continuously) and hormonal treatment. Data on demographics, clinical outcome, and toxicity were collected form the patients’ medical records for descriptive analyses. Results: The median follow-up was 23.5 months (range 11–36 months). Most of the patients were hormone receptor positive (70%). About 28% of the patients had multiple sites of metastasis while 16 patients (26.7%) had bone only metastasis and 11 patients (18.3%) had lung only metastasis. Most of our patients (63.3%) had no associated comorbidities. An overall response rate of 61.7% was achieved, including 2 complete responses (3.3%), and 13 partial responses (21.7%). Median progression-free survival was 15.9 months (95% confidence interval (CI) 13.56- 18.33), and the median overall survival was 19.9 months (95% CI 17.8-21.9). Most common grade 1-2 side effects were diarrhea (43.3%), followed by hand-foot syndrome (35%), and skin rash (13.3%). Grade 3–4 toxicities were identified as hand-foot syndrome (10%), diarrhea (6.6%).There were no symptomatic cardiac events. Tolerability data show that 45% of patients needed a lapatinib dose reduction, and 30% a treatment interruption due to toxicity, while treatment discontinuation occurred in 18.3% of the cases. Conclusion: Lapatinib based therapy in elderly patients with her2neu positive MBC was effective. However, it was not well tolerated especially when combined with chemotherapy.