Primary granulocyte-colony stimulating factor (GSCF) prophylaxis with dose-dense chemotherapy for early stage breast cancer is routine practice to prevent febrile neutropenia (FN). Our current practice administers 7 days of GCSF, which reduces the FN risk but is associated with extra toxicity and costs. We reviewed the rates of FN, neutropenia, hospital admissions and GCSF-related toxicity in early stage breast cancer patients receiving 7 days of GCSF with dose-dense epirubicin and cyclophosphamide (EC).
Between 2018 and 2021, patients treated for early stage breast cancer with dose-dense epirubicin (90mg/m2) and cyclophosphamide (600mg/m2) given every 2 weeks at two London hospitals were identified from chemotherapy prescribing records. Treatment delays, dose reductions, hospital admissions and GCSF-related toxicity were assessed from medical records.
Ninety-seven patients were identified, receiving 373 cycles of dose-dense EC. Median age was 46 years (25 – 60 yrs). GCSF was prescribed for 7 days (days 3-10) at 300mcg and 480mcg for 82 and 15 patients respectively according to baseline weight. Three patients had dose delays due to neutropenia, one of whom was non-compliant with GCSF. Risk of hospital admission for any reason was 5.2% per patient (1.3% /cycle). Two patients were admitted with neutropenic sepsis (risk 2.1%/patient, 0.5%/cycle). One was admitted on day 7 and the other on day 10 of the cycle. Both had a neutrophil count of 0.26 x 10ˆ9 /L. One subsequently died of COVID pneumonitis. Toxicity to GCSF was recorded in 41% of patients (16.4%/cycle). Musculoskeletal pain was the most common toxicity (95%), others included headache and injection site pain. Thirty-three patients had neutrophilia (> 7.5 x 10ˆ9/L) prior to a cycle (event rate 17.4%/cycle). Duration of GCSF was reduced in 16 patients; 12 due to toxicity, 1 due to neutrophilia, 1 due to raised neutrophil precursors and 2 not recorded. Of these, no patients had any further treatment delays or dose reductions.
The optimal duration of GCSF prophylaxis to reduce the FN risk with dose-dense regimens is unclear. Seven days of GCSF is associated with toxicity - a reduction to 5 days should be considered.
Clinical trial identification
Legal entity responsible for the study
Royal Free London NHS Foundation Trust.
Has not received any funding.
All authors have declared no conflicts of interest.