Use of Dose-dense EC Chemotherapy in Early Breast Cancer – Experience from Two London Hospitals

ABSTRACT

Purpose: Dose-dense (dd) chemotherapy regimens reduce breast cancer recurrence and mortality with no significant increase in non-cancer related mortality [1]. However, uptake is poor, probably due to concerns regarding toxicity. We aimed to quantify rates of toxicity and dose reduction in patients receiving dd epirubicin and cyclophosphamide (EC), and to identify any associated patient factors. Methods: This was a retrospective and prospective study. Patients receiving neoadjuvant or adjuvant dd EC (epirubicin 90 mg/m2 and cyclophosphamide 600 mg/m2 2-weekly) between 2018 and 2021 at two London hospitals were identified from electronic records. Baseline ECOG performance status (PS), incidence of dose delay, dose reduction and hospital admission were identified from electronic records. Results: 108 patients received dd EC, 49 (45%) in the neoadjuvant and 59 (55%) in the adjuvant setting, receiving a total of 422 cycles. Median age was 47 years (25–69 years). 105 patients (95%) had a baseline PS of 0;the other 6 (5%) a PS of 1. 99 patients (92%) received 4 cycles of dd EC as planned, of which 84 (78%) had no dose reductions. 3 patients were converted to the standard regimen due to toxicity. 5 patients had cycles omitted due to toxicity (n = 2) or other causes. One patient died due to COVID-19. 16 patients (15%) had a dose reduction. Treatment was delayed by at least 1 week in 18 patients (17%). The most common reasons for this were haematological toxicity (n = 6) and infection (n = 4). 6 patients (6%) had both delays and dose reductions. 8 patients (7%) were admitted to hospital during treatment, 4 of whom had febrile neutropenia. Conclusion: This real world data demonstrate that dd chemotherapy can be delivered in routine practice. The rates of dose reduction and delay were comparable to those found in standard regimes [1]. Patient selection by oncologists is an important factor. Reference [1] Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Increasing the dose intensity of chemotherapy by more frequent administration or sequential scheduling a patient-level meta-analysis of 37 298 women with early breast cancer in 26 randomised trials. Lancet 2019;393(10179)1440–52.