Supplementary Material for: Real world outcomes of FLOT vs CROSS regimens for patients with oesophagogastric cancers

Introduction:
Treatment of oesophageal (OC), gastro-oesophageal junction (GOJ) and gastric cancer (GC) includes either neoadjuvant CROSS for OC or GOJ or perioperative FLOT for OC, GOJ and GC adenocarcinoma. This study aims to describe the real-world outcomes of patients with GC, GOJ and OC treated with FLOT or CROSS and identify variables associated with efficacy through exploratory analysis. We also aimed to evaluate the comparison of FLOT and CROSS for the treatment of OC and GOJ adenocarcinomas.

Methods:
This is a retrospective observational study of patients with locally advanced OC, GOJ or GC treated with FLOT or CROSS between January 2015 to June 2021 in 5 cancer centers across Sydney, Australia. Long-rank test was used to compare survival estimated between subgroups. Hazard ratios for univariate and multivariate analysis were estimated with cox-proportional regression.

Results:
The study included 168 patients. The 24 month relapse free survival (RFS) and overall survival (OS) for FLOT was 59% and 69% respectively. The median RFS was 29.6 months and median OS was not reached. For CROSS, The 24 month RFS and OS was 55% and 63% with a median RFS and OS of 28.5 and 40.2 months, respectively. There was no difference in OS and RFS between the treatments. FLOT was less tolerable than CROSS with more dose reductions, treatment discontinuation and clinically relevant grade 3 and 4 toxicity. Neutrophil lymphocyte ratio (NLR)) was associated with survival for both treatments.

Conclusion:
Similar efficacy outcomes were seen in this real world population compared to the clinical trials for FLOT and CROSS.