Pegfilgrastim is typically administered 24 hours after chemotherapy per package insert; however some patients are unable or unwilling to return for this additional visit due to work or transportation especially with regimens consisting of infusional 5-FU. Same-day dosing eliminates need for this additional visit. Results from prior studies in other tumor types are inconclusive as few support same-day dosing whereas others show inferiority. Purpose of our study was to determine safety and efficacy of administering pegfilgrastim on same day as chemotherapy in patients with gastrointestinal (GI) malignancies.

A single-institution retrospective review was conducted of 69 patients with GI malignancies who received chemotherapy and same-day pegfilgrastim (6 mg) within 1 hour of completion of chemotherapy from Jan 2014 through Jan 2017. As per institutional guidelines, patients were counseled on risks of same-day pegfilgrastim prior to its administration. These patients were compared with a set of 70 patients who received pegfilgrastim 24-hours after completing the chemotherapy for GI cancers.

A total of 536 chemotherapy cycles in 69 patients were analyzed. Median absolute neutrophil count nadir for all cycles was 4538/uL (Range: 1160 - 25168). Grade 1 and 2 neutropenia developed in 6 of 536 (1%) cycles. Bone pain reported in 3 patients (4%). There were no episodes of grade 3 or 4 neutropenia or febrile neutropenia. None had dose reductions, chemotherapy delays, hospitalizations, or antibiotic use due to neutropenia.

We believe our study is the first in GI malignancies to report that same-day pegfilgrastim administration may be as effective and safe as next-day administration, benefiting patients and might reduce costs.