777PEvaluation of the introduction of primary G-CSF prophylaxis to the FLOT chemotherapy regimen

Abstract Background FLOT chemotherapy is a standard of care for patients with early gastric & gastroesophageal junction adenocarcinoma: 4 cycles pre- and 4 post-surgery. It was introduced at the Clatterbridge Cancer Centre in October 2017 following the presentation of FLOT4 trial data. Primary prophylaxis with GCSF was not part of the trial protocol but was allowed as per investigator’s discretion. As such GCSF was not included in the FLOT regimen initially in our centre. However, a significant number of patients could not proceed with their second cycle on time due to prolonged grade 3-4 neutropenia or neutropenic infection. Therefore, primary GCSF prophylaxis was introduced from day 5 of each cycle for 5 days at doses of 300 & 480 micrograms for patients with weight 70 kg, respectively. Methods Patients were identified from chemotherapy-prescribing records and data was collected from their electronic notes. As a primary objective we compared rates of dose delay because of neutropenia before and after introducing primary GCSF prophylaxis. We also looked at other reasons for dose delay & reduction. Results 47 patients started FLOT between October 2017 & July 2018; 41 were men and median age was 63.7 years (36-79). 2 patients had FLOT only in the adjuvant setting. In patients who started neoadjuvant FLOT, 27 patients (57.4%) went on to receive FLOT adjuvantly. 19 patients (40.4%) completed 8 cycles and the median number of cycles received was 5.6 (1-8 cycles). 13 patients had FLOT without primary GCSF prophylaxis, 61.6% of them had dose delays because of neutropenia. After the addition of primary GCSF prophylaxis, the rate of neutropenia resulting in dose delay fell to 2.9% (p = 0.00). 46.8% of patients had their treatment delayed for reasons other than neutropenia with the highest rates of deferral seen for non-neutropenic infection (10.6%) and nausea & vomiting (10.6%). 31.9% of patients had their treatment dose reduced; this was most commonly for diarrhoea (10.6%) and peripheral neuropathies (8.5%). Conclusions 61.6% of patients receiving the FLOT regimen had treatment delays because of neutropenia. Primary GCSF prophylaxis almost eliminated this problem and reduced the overall rate of dose delays. Therefore, primary GCSF prophylaxis should routinely be used with FLOT. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.