Proper dosage of primary pegylated G-CSF prophylactic use for breast cancer patients receiving adjuvant or neo-adjuvant chemotherapy.
e18354 Background: Myelosuppression during chemotherapy can lead to life-threatening infections, dose reductions, treatment delays, as well as prolonged hospitalizations, early morbidity, and early mortality. According to NCCN guideline, Pegfilgrastim 6mg per cycle is recommended for breast cancer patients receiving chemotherapy, and dosage modification based on body weight is not required. However, primary PEGylated G-CSF prophylaxis comes with significant extra cost, which has a great impact on health care resources, especially for patients without insurance coverage. Methods: We analyzed clinical data of patients, weighing between 45 and 65 kilogram, received a single subcutaneous PEGylated recombinant human G-CSF injection at fixed doses of either 3 mg or 6 mg per chemotherapy cycle approximately 24 hours after completion of each cycle of chemotherapy. Data for this retrospective study were obtained from Thyroid and Breast Surgical Department of the First Affiliated Hospital of Sun Yat-sen University between July 1, 2017, and October 31, 2017. Results: 41 cycles in 33 patients were included in 3mg PEGylated G-CSF group, and 46 cycles in 39 patients were included in 6mg PEGylated G-CSF group. Among chemotherapy cycles, the incidence of neutropenic event was19.5%and 2.2% in 3mg PEGylated G-CSF group and 6mg PEGylated G-CSF group, respectively. No patients experienced dose reductions or treatment delays in both groups. Using single-factor Logistic Regression Analysis, we found that dose of PEGylated G-CSF(3mg vs 6mg) was significantly associated with occurrence of neutropenic event(p = 0.028). Multi-factor Logistic Regression Analysis also showed that dose of PEGylated G-CSFwas significantly associated with occurrence of neutropenic event (p = 0.031). Conclusions: Our study showed that dose of prophylactic PEGylated G-CSF was significantly associated with occurrence of neutropenic events. So adequate dose of PEGylated G-CSF is important to reduce chemotherapy induced neutropenic events and to guarantee the quality of chemotherapy in patients with breast cancer.