5614 - Comparison of filgrastim and pegfilgrastim prophylaxis in sarcoma patients receiving highly myelosuppressive chemotherapy.

Background

Highly myelosuppressive chemotherapy (HMC) is the standard treatment for several types of sarcoma. Severe neutropenia is a common adverse event, which can lead to febrile neutropenia (FN) and major infections requiring hospitalization, with up to 15% mortality rate. Several trials showed an equal efficacy of filgrastim (F) and Peg-filgrastim (Peg-F) for preventing FN in many cancer types, but limited evidence is available in adult sarcoma patients (pts). We retrospectively compared the incidence of FN and hospitalization due to neutropenic infections in sarcoma pts treated with HMC with the support of either F or Peg-F.

Methods

We reviewed data of pts consecutively treated in our institution from Sep 2014 to Mar 2019. Inclusion criteria were: age >18 years; diagnosis of soft tissue sarcoma; at least 1 cycle of HMC supported by prophylactic F or Peg-F. Included HMC regimens were: doxorubicin ≥60 mg/m² (D) + ifosfamide ≥9 g/m² (IFO) +/- vincristine; high-dose IFO (≥12 g/m); IFO ≥9 g/m² + etoposide. Neutropenia prophylaxis included F (5-7 doses) or Peg-F (1 dose) according to physician‘s choice. χ²-Test was used to compare the outcomes; p ≤ 0.05 was considered significant.

Results

79 pts were found eligible, receiving 330 cycles of HMC. F and peg-F were used as prophylaxis in 66.6% (n = 220) and 33.3% (n = 110) of cases, respectively. The rate of FN was higher in the Peg-F group compared to the F group (11.8% vs 6.8, p = 0.12), while the rate of cycles complicated by a hospitalization was 9% and 3.2% (p = 0.02), respectively. 8/16 hospitalizations were due to pneumonia. One death during hospitalization occurred in the Peg-F group. 70% of hospitalizations occurred in metastatic pts, whereas 30% occurred during adjuvant treatments.

Conclusions

The use of peg-F was associated with a significantly higher rate of neutropenic infections requiring hospitalization compared with F in adult sarcoma pts receiving HMC. FN rate was numerically higher in pts receiving peg-F, not reaching statistical significance. These data suggest that F prophylaxis may be preferred in this setting to peg-F. Overall, prophylaxis with both agents provided a relatively low rate of hospitalizations and FN, compared with the myelosuppressive potential of the regimens.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.