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.