Retreatment with trastuzumab plus chemotherapy and/or hormonal therapy may be safe and effective among patients with HER2-positive breast cancer recurrence, according to a study published in Breast Cancer: Basic and Clinical Research.1
Guideline recommendations for the treatment of HER2-positive breast cancer include anti-HER2 agents such as trastuzumab, pertuzumab, or T-DM1, in combination with chemotherapy. Trastuzumab plus chemotherapy is a common first-line option, but its effectiveness among patients with recurrence who received trastuzumab during perioperative therapy was the focus of this observational study in Japan.
Researchers enrolled 34 patients with breast cancer who relapsed after receiving primary systemic therapy with trastuzumab. Eligible patients had received trastuzumab for 10 months or more as perioperative therapy, had evaluable lesions, and a left ventricular ejection fraction (LVEF) ≥50% within 4 weeks of initiating therapy. Patients were retreated with trastuzumab monotherapy, or trastuzumab plus chemotherapy and/or hormonal therapy.
After a median follow-up of 23.7 months, results showed that the median progression-free survival (PFS) was 10.6 months (95% CI, 6.4-18.9). The 1-year progression-free survival (PFS) rate was 46.9% (95% CI, 29.2-62.9) and the 2-year PFS was 29.8% (95% CI, 15.0-46.3). Patients treated with trastuzumab plus chemotherapy had a median PFS of 13.0 months.
The 1- and 2-year overall survival rates were 93.9% (95% CI, 77.9-98.4) and 84.8% (67.4-93.4), respectively.
Complete or partial responses were observed among patients treated with trastuzumab plus chemotherapy and trastuzumab plus chemotherapy and hormonal therapy; no patients in the trastuzumab monotherapy or trastuzumab plus hormonal therapy groups responded to treatment.
No trastuzumab-induced grade 3 to 4 adverse events were reported.
The authors concluded that “trastuzumab should be used in combination with chemotherapy and/or hormonal therapy for retreatment. Retreatment with trastuzumab is safe.”
- Yamashiro H, Sawaki M, Masuda N, et al. Survival outcomes of retreatment with trastuzumab and cytotoxic chemotherapy for HER2-positive recurrent patients with breast cancer who had been treated with neo/adjuvant trastuzumab plus multidrug chemotherapy: a Japanese multicenter observational study [published online July 5, 2018]. Breast Cancer (Auckl). doi: 10.1177/1178223418786243