Real-World Outcomes for Localised Gastro-Oesophageal Adenocarcinoma Cancer Treated with Perioperative FLOT and Prophylactic GCSF Support in a Single Asian Centre.

Background: Perioperative FLOT (5-fluorouracil, oxaliplatin and docetaxel) is a standard of care for patients with locally advanced gastro-oesophageal adenocarcinoma (GEA) in Western guidelines, but its use is limited in Asian patients. We report outcomes from a single Asian centre of perioperative FLOT with concomitant granulocyte colony-stimulating factor (GCSF) prophylaxis.

Methods: A retrospective analysis of all 56 stage II to III GEA patients treated with perioperative FLOT at the National Cancer Centre Singapore between June 2017 and February 2024 was performed. All patients were discussed at a multidisciplinary tumour board, underwent preoperative laparoscopic staging, and received prophylactic GCSF with perioperative FLOT. Surgery was performed across four partner institutions. The primary endpoints were the tolerability of FLOT and pathological complete response (pCR). A univariate analysis of factors associated with survival and adverse events was also performed.

Results: Overall, 33 patients (58.9%) completed eight cycles of pre- and postoperative FLOT, and 92.9% underwent resection. The commonest grade 3 to 4 adverse events (AEs) were diarrhoea (10.7%) and neutropenia (5.6%). The 30- and 90-day postoperative mortality rates were 0% and 1.9%, respectively. In resected tumours, the pCR was 15.4%. The median DFS was 27.5 months, but the median OS was not reached. The values for 1-, 2-, and 3-year DFS were 74.6%, 61.0%, and 46.5%, respectively. The values for 1-, 2-, and 3-year OS were 85.0%, 67.4%, and 61.0%, respectively. In the univariate analysis of patients who underwent resection, an ECOG status of 0 was associated with better DFS, while ypN0, R0 resection, and pathological stages 0-II were associated with better DFS and OS. Patients ≥ 65 years benefited from FLOT similarly to those <65 years in terms of DFS (HR 1.03; p = 0.940) and OS (HR 1.08; p = 0.869), with similar rates of grade 3 to 4 AEs. Patients with a higher housing index (HI) were less likely to experience ≥grade 3 AEs compared to those with a lower HI (OR 0.16, p = 0.029).

Conclusions: This study presents a unique real-world Asian experience of perioperative FLOT with prophylactic GCSF use, with low rates of G3 to 4 neutropenia. The tolerability of FLOT was similar to that reported in Western populations. Furthermore, similar survival and rates of grade 3 to 4 AEs were observed in elderly patients. Patients of lower socioeconomic status were more likely to experience severe AEs, highlighting the need to proactively support vulnerable groups during treatment.