Safety and efficacy of administering reduced doses of pegylated recombinant human granulocyte‐colony stimulating factors in patients treated with cisplatin and etoposide for small cell carcinoma: A retrospective study

BACKGROUND: The aim of this study was to discuss the safety and efficacy of administering reduced doses (3 mg) of pegylated recombinant human granulocyte‐colony stimulating factor (PEG‐rhG‐CSF) at approximately 24 h or up to three days following treatment with etoposide and cisplatin (EP). METHODS: A total of 104 cycles from 31 patients were divided into a PEG‐rhG‐CSF prophylaxis group (PP‐Group) and a control group (No‐PP‐Group). The PP‐Group received a reduced dose of 3 mg of PEG‐rhG‐CSF within a minimum of 15 h and a maximum of 72 h following EP chemotherapy, while the rest did not receive any G‐CSF prophylaxis (No‐PP‐Group). For both groups, complete blood counts, incidence of febrile neutropenia (FN), grade III or IV neutropenia, and the use of antibiotics to treat neutropenia were recorded. RESULTS: There was statistically no significant difference in the incidence of FN (0% vs. 1.4%, p = 1), antibiotic use due to neutropenia (0% vs. 2.7%, p = 0.881), estimated lowest mean marginal (EM) platelet (106.56 × 10(9)/L vs. 127.70 × 10(9)/L, p = 0.056) and hemoglobin (110.48 g/L vs. 110.14 g/L, p = 0.906) levels between the two groups. However, when compared with the No‐PP‐group, the white blood cell count in the PP‐group was significantly higher (EM means: 4.95 × 10(9)/L vs. 2.80 × 10(9)/L, p < 0.01), while the incidence of grade III or IV neutropenia was significantly lower (9.1% vs. 68.1%, p < 0.01). CONCLUSIONS: The administration of a low dose (3 mg) of PEG‐rhG‐CSF within approximately 24 h or up to three days following EP treatment is safe and effective at reducing the risk of neutropenia. These findings bring a more flexible administration interval between PEG‐rhG‐CSF and EP treatment.